Residential Development in Subdivisions and RD Districts

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BYLAW: Residential Development in Subdivisions and RD Districts

MUNICIPALITY: Lexington, MA

DATE ADOPTED: 1996

PURPOSE OF BYLAW:

A proposed amendment to the Residential Development section (section 9) of the Lexington Zoning Bylaw that encourages Cluster Subdivision as a means to address Lexington's remaining undeveloped and underdeveloped areas while upholding Lexington's broader public objectives, namely:

• Protect Open Space

• Encourage Site Planning More Sensitive to the Natural Features of Land

• Encourage Alternative Housing Types - Particularly those that meet the needs of the town's changing age groups

• Encourage Alternative Housing Types - Particularly those that have a positive revenue/cost ratio for Town finances

• Encourage Development Compatible with Existing Neighborhoods of Single Family Houses

• The Planning Board believes this is the most important zoning amendment it has proposed during the 1990's.

FOR MORE INFORMATION ON THIS BYLAW:

Contact Lexington Planning Department, Planning Director,
Phone: (781)862-0500 x 245 Fax: (781)861-2748

 TEXT OF THE BYLAW

CONTENTS:

ARTICLE 29 COMPREHENSIVE REVISION, SECTION 9, RESIDENTIAL DEVELOPMENT IN SUBDIVISIONS AND RD DISTRICTS

TABLE 1: PRINCIPAL CHARACTERISTICS OF CLUSTER AND CONVENTIONAL SUBDIVISIONS

TABLE 2: THE FIVE IMPACT MEASURES

INCENTIVES

PUBLIC POLICY OBJECTIVES

TABLE 3: OCCUPANCY OF HOUSING UNITS BY AGE GROUP

SECTION 9. RESIDENTIAL DEVELOPMENTS

9.2 SCHEDULE OF PERMITTED BUILDINGS, DENSITY AND DIMENSIONAL STANDARDS

9.3 GENERAL PROVISIONS APPLICABLE TO ALL RESIDENTIAL DEVELOPMENTS

9.4 CONVENTIONAL SUBDIVISION

9.5 CLUSTER SUBDIVISION, SPECIAL RESIDENTIAL DEVELOPMENT

9.6 DEVELOPMENTS WITH SIGNIFICANT PUBLIC BENEFIT (DSPB)

9.7 SPECIAL PERMITS: PROCEDURES. CRITERIA

9.8 CONVERSION OF MUNICIPAL BUILDINGS AND SURPLUS MUNICIPAL LAND

 

ARTICLE 29 COMPREHENSIVE REVISION, SECTION 9, RESIDENTIAL DEVELOPMENT IN SUBDIVISIONS AND RD DISTRICTS

This proposed amendment is about the future of residential development in Lexington. The Planning Board believes this is the most important zoning amendment it has proposed during the 1990's.

This comprehensive revision of Section 9 of the Zoning By-Law has several objectives:

• Protect Open Space

• Encourage Site Planning More Sensitive to the Natural Features of Land

• Encourage Alternative Housing Types - Particularly those that meet the needs of the town's changing age groups

• Encourage Alternative Housing Types - Particularly those that have a positive revenue/cost ratio for Town finances

• Encourage Development Compatible with Existing Neighborhoods of Single Family Houses

• Lexington Is Not Fully Developed

We are often told this type of amendment is not necessary because Lexington is almost fully developed. Not so! There are about 222 acres of vacant land and about 1407 acres of underdevel-oped land remaining in town. This data is based on parcels that have at least 50,000 sq. ft. or more in the RS, One Family Dwelling, district and 100,000 sq. ft. or more in the RO, One Family Dwelling, district.

"Underdeveloped" in this context means the land is now developed to less than half of what is now permitted by the Zoning By-Law. In the single family districts, underdeveloped usually means a large tract of land with one older house on it.

To help the reader visualize what these numbers mean, the Battle Green in Lexington Center is about 110,000 square feet or about 2.5 acres. The land in town susceptible to development is the equivalent of about 688 Battle Greens - but without Captain Parker's statue.

Figure 1 shows there is a total of about 5,335 acres of land in the single family and two family zoning districts that is in private ownership. Of those 5,335 acres, 3,929 are already developed. The 1,407 acres that might presently qualify for development under Section 9 of the Zoning Bylaw are about 26 percent of that land. How we treat that land will affect the future appearance and character of the town.

CONVENTIONAL VS. CLUSTER SUBDIVISION

The two site plans on the cover of this report show the difference in layout between a conventional and a cluster subdivision. Table 1 below contrasts the two types of subdivision both as they are permitted in the existing Zoning By-Law and in the proposed amendment.

TABLE 1: PRINCIPAL CHARACTERISTICS OF CLUSTER AND CONVENTIONAL SUBDIVISIONS

CLUSTER SUBDIVISION	CONVENTIONAL SUBDIVISION
Open space in common and in private yards. Buildings grouped/sited together. Design emphasis on natural features of land.  Building Types Permitted: One Family Detached One Family Attached One Family with Accessory Apartment* Two Family Town House   Minimum 25% in common open space. * Proposed in Article 29	Open land in yards of privately owned lots; no common open space. Individual buildings on separate lots. Design emphasis on geometry - lot frontage, area, lot width.   Building Types Permitted: One Family Detached   No requirement for common open space.

Practically No Cluster Development Recently

In recent years practically all of the land that has been developed in subdivisions has been in "conventional" subdivisions with very large one-family dwellings described as "jumbo" houses. This amendment provides two other "cluster" development alternatives for developers to choose. This amendment proposes no changes in the standards for "conventional" subdivisions.

The Lexington Zoning By-Law has permitted cluster subdivision since 1966 and a number were built in the 1960s and 1970s. However, of the 51 subdivisions approved since 1980, only 12 have any cluster subdivision features; and only three (Mason's Hollow on Massachusetts Avenue behind the historic Mason house, Turnburry Hill, off Hill Street, and Orchard Crossing, off Sanderson Road) have housing types other than detached single family houses.

In the earlier years, developers met the requirement for 25 percent common open space by giving the Town the undevelopable, often wetland land that could not be built on . In the proposed amendment, only dry usable land may qualify as common open space.

Comparing Conventional and Cluster Subdivisions

By Number and By Impact of Dwelling Units:

The requirement that no more dwelling units may be built in a cluster subdivision than in a conventional subdivision has been based on the assumption that all dwelling units have equivalent impacts. With advances in the Town's data processing capabilities, we can now show that different dwelling units have different impacts.

The Planning Board believes that when Town Meeting Members have expressed concern about the density of development, they were concerned about the assumed impact of the development and not the numerical calculation of the units.

The proposed amendment, in subsection 9.5.4., proposes that all housing types be evaluated according to five impact measures - the gross floor area, living area, site coverage, occupancy and motor vehicle "trip generation" of the dwelling units - and not on the basis of the number of dwelling units. The impact of a cluster subdivision under this amendment should not be greater than a comparable conventional subdivision.

The Planning Department has analyzed the characteristics of all housing built in Lexington since 1980. The data in Tables 2 and 3 are based on records in the Building Department, the Assessors Office and the Town Census. The Department analyzed the characteristics of all single family houses built in conventional subdivisions since 1991. The Department has also analyzed the characteristics of all other types of dwelling units, such as semi-attached dwellings and townhouses. Since 1985, the Zoning By-Law has permitted those types of housing to be constructed in cluster subdivisions in single family zoning districts. Only a handful have been built.

TABLE 2: THE FIVE IMPACT MEASURES

	Number of Units in Sample	Gross Floor Area, sq. ft.	Living Area, sq. ft.	Site Coverage, sq. ft.	Number of Occupants	Vehicle Trips
One-Family Detached	53	7,200	4,700	2,900	5	15.8
One Family Attached	98	3,356	1,868	1,771	4	8.8
Townhouse	225	2,928	1,766	1,414	2	8.8

The data in Table 2 is the 75 th percentile of all units in the range. That percentile was chosen because, according to the proposed amendment, the maximum impacts of the other types of housing allowed in a cluster subdivision can not exceed the 75th percentile of the houses in single family subdivisions. If a larger house in the range were used, some huge houses built in recent years would become the standard. If the median was used instead , th other types of housing allowed in a cluster subdivi sion could not exceed the midpoint of the range of large single family houses hardly an incentive to encourage greater use of cluster development .

As Table 2 shows, the other types of housing are significantly smaller than the large houses being built in conventional subdivisions.

Analysis of the occupancy data from the 1995 Town Census shows both the difference in age group orientation and the potential impact, in school aged children and pre-school children, on the Town's budget. The data shows that large single family houses in conventional subdivisions are oriented to middle aged families with school aged children. The other types of housing are oriented to smaller households, often composed of empty nesters and retirees. The occupancy characteristics by age groups of the two types of housing are nearly the mirror image of each other.

We must rely on limited data taken from the Institute of Transportation Engineers to evaluate traffic impacts. The ITE has a number of motor vehicle "trip generation" studies of single family houses but very few studies of other types of housing. We are not able to obtain data on traffic patterns, broken down by number of bedrooms, unit size and price, as we are with the housing and occupancy data from Town records. The trip generation rates (75th percentile) are:

Single family house in conventional subdivision 15.8 trips

Semi-attached dwelling 8.8 trips

Townhouse 8.8 trips

Calculating the Maximum Development Potential of a Cluster Subdivision

The maximum development permitted in a cluster subdivision for each of the five impact measures is limited, in subparagraph 9.5.4.1., to the 75th percentile of the corresponding impact measure for single family houses in conventional subdivisions.

A developer can quickly calculate the maximum permitted development in a cluster subdivision, by using the step-by-step procedure set forth in section 9.5.4.3 (see page 10 in the Motion following this report.) By simply entering the area of a lot and the minimum lot area for the zoning district in which the lot is located into a spreadsheet (the Worksheet on page 11 of the Motion), a developer can quickly determine the maximum gross floor area, maximum living area and maximum site coverage that will be allowed for the total development. The developer can then develop a proposal with a mix of units that best responds to market considerations, costs of production and site and location factors. As long as none of those three factors exceed the maxima in section 9.5.4.3, that part of the development can be approved.

The developer must obtain data on the other two measures of impact, occupancy characteristics and motor vehicle trip generation, from the Planning Board. The Board has published and will periodically revise and publish data on occupancy which can be broken down by number of bedrooms, size of unit, price range and type of building for each of the four other types of dwelling units, e.g. semi-attached, two-family, townhouse and accessory apartment, that are permitted. In general, one- and two-bedroom units in both one-family attached and townhouses have less than two occupants (ranging from 1.3 to 1.8 persons) and three bedroom units have about 2.35 persons.

Preliminary mathematical analysis indicates that the data on occupancy characteristics and motor vehicle trip generation will be the principal control on development.

The theoretical maxima in a cluster subdivision based on impact measures are only one of the factors the Planning Board is required to consider in approving a cluster subdivision. Some of the mathematically, spreadsheet oriented Lexingtonians have focused exclusively on these formulas. After the math, the developer still has to prepare a site plan that meets a number of design criteria such as protection of the natural features of the land, the siting of buildings in relation to each other and to the common open space, and the relationship of the scale of the development to the adjoining single family neighborhood. These criteria are listed in paragraph 9.5.5. on page 12 of the Motion. Paragraph 9.5.3.3. (page 9 of the Motion) states no one is entitled to the maximum development based on calculation of impact measures.

INCENTIVES

There are strong public policy arguments for cluster development. So why have there not been more cluster subdivision recently? The answer is not that developers are greedy or misdirected. They make business decisions that respond to the opportunities presented to them. We must understand these constraints and offer incentives if we are to have more cluster subdivisions built.

Members of the Planning Board had four meetings with developers, land planners, lawyers and civil engineers active in development in our single family districts. The Board learned there are practical constraints, from the development perspec-tive, that work against more cluster subdivision. Many of the constraints are economic but others deal with the regulatory/approval process.

Economic and Marketing Considerations

Houses in cluster subdivisions, whether single family houses or other types of housing, are typically smaller. The difference in the sales price between a larger, more expensive house in a conventional subdivision and a smaller house in a cluster subdivision can easily be $300,000 or more.

The price of land acquisition is dictated by the number of houses a developer of a conventional subdivision can build. The developer of a cluster subdivision will have to absorb that land cost in smaller, lower priced houses. If zoning limits the number of units to the same as in a conventional subdivision, the choice is obvious.

Developers tell us that buyers are now more leery of condominiums for financial reasons and of condominium associations or homeowners associations due to the hassles of residential democracy. They want to control their own lot and house. Having been burned in the 80's, banks are reluctant to finance condos or homeowners associations.

Regulatory and Development Requirements

A cluster subdivision, which requires a customized design applicable to one piece of land, is more complicated and requires more professional resources - such as a land planner, a lawyer, or an architect - and more difficult marketing to consumers. A conventional subdivision is a more familiar product to developers and consumers. Civil engineering firms now have CAD (Computer Aided Design) systems that can "design" a subdivision with input of basic data. These additional professional resources for a cluster subdivision mean higher development costs.

The concept of a cluster subdivision is that the Planning Board waives or reduces the usual dimensional requirements, i.e. lot area, yard setback, applicable to a conventional subdivision, in order to allow buildings to be grouped closer together and to create common open space. This set of waivers etc. can result in a better site plan, more adaptable to the peculiarities of a site's topography or tree cover or other natural features or relationship to the adjoining neighborhood. However, this flexibility can only be achieved through a zoning special permit which requires a 4/5th vote of the Planning Board. Developers in Lexington, and in many other towns, want to avoid any process that is discretionary or uses criteria beyond numbers and geometry. Developers prefer a process that is predictable and fast.

It is not surprising that developers choose a conventional subdivision over a cluster process characterized as it is by complexity, delay, and uncertainty that requires more time, more money, and more risk for less reward. Many will continue to develop conventional subdivisions. Lexington needs to encourage more to try the cluster subdivision process. The existing Zoning By-Law offers only one economically feasible choice to developers. This proposed amendment seeks to provide other attractive alternatives.

During our discussions with developers, several referred to letting the forces of the "free market" operate. Real estate development is not a "free" market but is highly regulated. The Town, through what its Zoning By-Law allows, and doesn't allow, is an important regulator. The proposed amendment will offer more choices and broaden the market while pursuing public policy objectives.

Other Incentives

The proposed amendment offers to level the economic playing field so that a cluster subdivision is economically competitive with a conventional subdivision by removing the limit on the same number of dwelling units.

Another incentive is in the formula for calculating the maximum amount of permitted develop-ment. The incentive is that the divisor is based on lot area only, and does not consider wetlands or allow for the fact that road construction in a conventional subdivision is typically longer.

The proposed amendment offers a third choice not now available to developers. A "development with significant public benefit" (See subsection 9.6 of the Motion on pages 14-16.) offers a developer the economic incentive of up to a 25 percent increase in permitted development in exchange for public facilities or amenities.

The Planning Board has agreed to "fast track" an application for a cluster subdivision to deal with the time factor. However, the Board will not abdicate its discretion and will not approve developments that do not meet broader public objectives.

PUBLIC POLICY OBJECTIVES

1. Protect Open Space - In the Town's stressed fiscal situation, there is less money available, than in earlier years, for the acquisition of open space due to greater competition from other necessary capital expenditures. Lexington needs to use all the tools available to protect open space including those that do not require purchase of a property or its development rights. The extraordinarily deep front yard setback negotiated for the Youville Place development on Pelham Road (Article 31 of the 1996 Town Meeting) is one example. The opportunities, for reservation of open space and quid pro quo tradeoff, that this proposal offers are other examples of ways to protect open space that do not affect the tax levy.

2. Encourage More Sensitive Site Planning - A conventional subdivision essentially superimposes a geometric grid on land regardless of its natural features. The land remaining in town for development does not lend itself to geometric grids. It often has steep slopes and wetlands. It is mostly the marginal land that was bypassed by development in earlier years. The custom design nature of a cluster subdivision, the flexibility afforded by the waiver of usual dimensional standards, and the criteria the Planning Board is required to use, are better suited to this more difficult land.

The proposed amendment should not result in the development of any more land than would otherwise be developed in conventional subdivisions. It should not make development easier but should make it better.

3. Encourage Alternative Housing Types - Age Groups - As documented in the Planning Department's "Socio-Economic Characteristics of Lexington, Volume One, Population", Lexington is experiencing a rapid increase in its older population. The Planning Department has further analyzed the age distribution of the population by households. This study is based on the 1995 Town Census, the latest available.

TABLE 3: OCCUPANCY OF HOUSING UNITS BY AGE GROUP

TYPE OF HOUSING UNIT	NUMBER	PERCENTAGE
All Housing Units WITH Children
with schoolage children ONLY	2,368	23%
with schoolage children AND pre-schoolers	519	5%
with pre-schoolers ONLY	433	4%
Subtotal	3,320	32%
All Housing Units WITHOUT Children
with senior citizens ONLY	2,309	22%
with senior citizens AND other adults	1,211	12%
with other adults ONLY (no seniors)	3,587	34%
Subtotal	7,107	68%
Total Households (age of occupants known)	10,427	100%

Source: Planning Department from Town Clerk Annual Town Census 1/1/1995

Table 3, shows that more than one third of the housing units in Lexington are occupied by either senior citizens only (22%) or senior citizens living with other adults (12%). The combined 34% of the households in which seniors live is slightly higher than the 32% in which children of any age live. When the 34% of the housing units occupied by other adults are combined with housing in which seniors live, 68% of the housing units are child free.

Conventional subdivisions typically have large houses with 4, 5, or 6 bedrooms oriented to families with children. Those houses bypass a potential housing need or market for adults without children.

Developers who may be interested in building housing for smaller households are now practically forced into seeking a rezoning. Since there is only one Town Meeting a year at which zoning articles are considered, many developer abandon the idea of that type of housing because of the wait and the uncertainty. Preparing a rezoning proposal is expensive - adding potentially $25,000 - $75,000 to the development cost. Faced with these considerations, most developers simply build a conventional subdivision instead.

The proposed amendment offers an opportunity to build small developments of housing for smaller households at a scale and in a building form compatible with single family neighborhoods.

4. Encourage Alternative Housing Types - Fiscal Considerations - Lexington traditionally has separated its land use/zoning decisions from its fiscal decisions. With the Town's financial dilemma, land use/zoning decisions need to give greater consideration to the Town's fiscal situation. The 68% of the housing units in town that do not have children generally do not have significant impacts on the Town's budget and many of them provide a positive revenue/cost ratio. From a fiscal perspective, it makes sense to increase the number of those types of housing units. Similarly it makes fiscal sense to offer more choices to developers so that they do not build only large single family houses that have school aged children and the greatest impact on the Town budget.

With nearly 11,000 housing units already in Lexington and the relatively low volume of development that is likely to occur, a shift in the type of housing built is certainly not a fiscal panacea. However, it is one action that Lexington can take.

The "development with significant public benefit" alternative, in which a developer can earn greater development potential in exchange for providing a variety of public facilities and services is an opportunity to obtain public benefits without the Town appropriating money.

5. Encourage Development Compatible with Existing Neighborhoods - Cluster subdivisions typically include a high proportion of smaller single family houses closer to the size and scale of existing neighborhoods. The other types of housing that the Zoning By-Law allows have contact with the ground on at least two sides. Apartment buildings and buildings with units on the second or third floor are not permitted. Many will be individually owned. Many will have the exterior appearance of a single family house although there will be more than one dwelling unit inside.

One of the criteria for approval (See 9.5.5.c.3 on page 12 of the Motion) is that the buildings relate to the predominant characteristics of the adjacent detached dwellings in the adjoining neighbor-hood with respect to scale, mass, setback, proportions and exterior materials.

Recommendation: The Planning Board recommends that Article 29 be approved.

SECTION 9. RESIDENTIAL DEVELOPMENTS

9.1 OBJECTIVES AND APPLICABILITY

9.1.1 The provisions of this section are intended to:

• Ensure that the development of additional housing does not detract from the livability, scale, character or economic value of existing residential neighborhoods;

• Encourage greater diversity of housing opportunities in Lexington to meet the needs of a population which is diversified with respect to number of persons in a household, and income;

• Provide greater choice in the type of housing available to correspond to the varying needs of town residents in different stages of their life cycle;

• Encourage the development of housing affordable to low-, moderate- and middle-income households;

• Provide greater flexibility and design freedom in the development of those tracts of land which lend themselves to planned development;

• Promote a high standard in the design of development sites and of individual buildings;

• Encourage the preservation of open space for conservation, outdoor recreation, park purposes, or public access to open space, in conjunction with residential development;

• Encourage the preservation, and minimum disruption, of the existing natural features of land and to minimize impacts on environmentally sensitive areas;

• Preserve, where applicable, historically or architecturally significant buildings or places;

• Permit ostensibly different types of structures and residential uses to be combined in a planned interrelationship;

• Facilitate a detailed review, by town officials and by the public, of those developments which either: 1) have an impact on public facilities and services and on adjoining land, or 2) are large enough to constitute a self-contained environment;

• Promote the efficient and economical provision of public facilities such as utilities and streets;

• Assure that the number of dwelling units allowed will be compatible with surrounding land uses, and that traffic and public services will not be adversely impacted;

9.1.2 No building permit shall be issued for a dwelling which is part of a development on a tract of three or more dwelling units, or their equivalent in housing accommodations not classified as dwelling units, except in accordance with the provisions of this section.

9.1.3 In an RO, RS or RT district, a residential development of three or more dwelling units may be:

a conventional (conv) subdivision,

cluster (clus) subdivision, with the tract divided into separate lots for dwellings and common open space, or

a special (spec) residential development in which the tract may be in one ownership or may be divided into separate lots for dwellings and common open space,

a development with significant public benefit (DSPB).

9.1.4 The procedure for a cluster subdivision or a special residential development or a development with significant public benefit (DSPB) is not intended be used as an alternative to allow the construction of a conventional subdivision that could not otherwise comply with the standards and requirements set forth in this By-Law or in the "Development Regulations".

9.2 SCHEDULE OF PERMITTED BUILDINGS, DENSITY AND DIMENSIONAL STANDARDS

(Applicable to the residential development as a whole.)

Conv. = conventional subdivision, Clus. = cluster subdivision Spec. = special residential development DSPB = development with significant public benefit NR = no requirement sf = square feet ft = linear feet

		ZONING DISTRICT
RO		RS, RT		RD
Type of Development		Conv.	Clus. Spec. DSPB	Conv.	Clus. Spec. DSPB
9.2.1 Minimum Area of Tract to be Developed		NR*	100,000 sf	NR*	50,000 sf	125,000 sf
* No requirement for tract as a whole; individual lots must comply with Table 2; right-of-way must comply with Subdivision Regulations
9.2.2 Types of Buildings* Permitted
a. One-Family Detached		Yes	Yes	Yes	Yes	Yes
b. One-family Attached, *Yes in RT		No	SP	No*	SP*	Yes
c. Accessory Apartment		Yes	Yes	Yes	Yes	Yes
d. Two-family *Yes in RT		No	SP	No*	SP*	Yes
e. Townhouse		No	SP	No	SP	Yes
f. Three-, Four-Family		No	No**	No	No**	Yes
g. Multi-Family		No	No**	No	No**	Yes
h. Rooming House		No	No**	No	No**	Yes
i. Group Quarters *(Yes, where accessory to a religious or educational use)		No*	No*,**	No*	No*,**	Yes
j. Independent Living Residence		No	No**	No	No**	Yes
k. Assisted Living Residence		No	No**	No	No**	Yes
l. Congregate Living Facility		No	No**	No	No**	Yes
m. Long-Term Care Facility		No	No	No	No	Yes
n. Conversion of Municipal Building (See 9.8)		SPS	SPS	SPS	SPS	Yes
* See definitions in Section 2 ** See also 9.5.6.c.
9.2.3 Minimum Frontage of the Tract on An Existing Street		50 ft.	100 ft.	50 ft.	100 ft.	100 ft.
9.2.4 Minimum Yard Setback on Perimeter of Tract
a. Front Yard		NR*	NR*	NR*	NR*	40 ft
b. Side Yard, Rear Yard		NR*	NR*	NR*	NR*	30 ft
*No requirement for development as a whole; individual buildings subject to Table 2
9.2.5 Maximum Impervious Surface Ratio (See paragraph 7.9)		NR*	0.15	NR*	0.20	0.40
*No requirement for a conventional subdivision as a whole; see 9.4.4 for individual lots
9.2.6 Minimum Common Open Space (See 9.3.4) As Percentage of Developable Site Area (See 7.9.1.)		NR	clus. 25% spec * DSPB *	NR	clus 25% spec * DSPB *	10%
* At least 10 percent, but see also paragraph 9.5.7 and 9.6.7.
9.2.7 Minimum Usable Open Space (See 9.3.5) per Dwelling Unit, or Equivalent		5,000 sf	5,000 sf	3,500 sf	3,500 sf	1,500 sf
9.2.8 Maximum Height of Dwellings		40 ft	40 ft	40 ft	40 ft	40 ft

9.2.9 EQUIVALENT DENSITY, RESIDENTIAL ACCOMMODA-TIONS NOT IN DWELLING UNITS

Where a residential facility is not arranged in dwelling units and individual living units do not have separate kitchen and dining facili-ties, for the purpose of cal-culating density and other dimensional standards, the following shall be considered equivalent to one dwelling unit:

1,000 square feet of gross floor area in a long-term care facility

1,200 square feet of gross floor area in group quarters, an assisted living residence facility or a congregate living facility that does not have dwelling units.

Where a residential facility that is not arranged in dwelling units provides at least one meal a day in a common dining area, served by a central kitchen, to the occupants of the living units, the presence of small cooking equipment for the convenience of occupants of the individual living units will not classify the living unit as a dwelling unit.

9.3 GENERAL PROVISIONS APPLICABLE TO ALL RESIDENTIAL DEVELOPMENTS

9.3.1 COMPLIANCE WITH OTHER RULES AND REGULATIONS

The construction of community services, such as utilities, and of streets and interior drives shall comply with the requirements of the Planning Board's "Development Regulations". Nothing contained herein shall exempt a subdivision from complying with the provisions of the "Development Regulations" and of the Subdivision Control Law.

9.3.2 PARTS OF DWELLING UNITS BELOW GROUND

No part of a dwelling unit, an assisted living unit or a rooming unit used for sleeping, cooking, dining or bathroom purposes may be located in a cellar. (See Definition.) A part of a dwelling unit, an assisted living unit or a rooming unit used for such purposes may be located in a basement (See Definition.), provided the vertical height between the horizontal plane of the ceiling and the finished grade of the ground adjoining the dwelling unit is at least six feet for at least two-thirds of the length of the exterior walls of all rooms used for such purposes.

9.3.3 NON-RESIDENTIAL USES

In an RD district, the planned residential development may also include commercial uses provided:

such uses serve primarily the residents of the development,

such uses are conducted within and may be entered only from within a principal building,

there is no external evidence of such uses visible beyond the development tract, and

the appearance and character of the commercial uses are compatible with a residential development.

9.3.4 COMMON OPEN SPACE

9.3.4.1 PURPOSE

Common open space is intended to provide open, natural area on a site for the general use of most, or all, the occupants of a residential development with three or more dwelling units. It is intended to provide for the active and passive recreational use and visual enjoyment of the occupants of a residential development and, in some cases, for residents of the adjacent neighborhood and the public generally.

9.3.4.2 LOCATION, CONDITION

Where required or provided, common open space shall be land that:

may be in one or more parcels of a size and shape appropriate for the intended use;

meets the requirements for developable site area as that term is defined in paragraph 7.9.1; and

all occupants of a development have the right to use.

9.3.4.3 OWNERSHIP

Common open space may be conveyed to:

and accepted by the Town to ensure its perpetual use as open space, conservation, recreation or park land; or

a legal association comprised of the owners of the development, which may include homeowners or owners of condominium or cooperative units; or

a non-profit organization the principal purpose of which is the conservation of open space.

When such open space is conveyed to persons or entities other than the Town, an easement over such land shall be granted to the Town to ensure its perpetual use as open space, conservation, recreation or park land.

9.3.4.4 ACCESSORY PARKING OR STRUCTURES

A maximum of 20 percent of common open space may be devoted to parking or structures used for, or accessory to, active outdoor recreation provided such parking or structures are consistent with the open space uses of such land.

9.3.5 USABLE OPEN SPACE

9.3.5.1 PURPOSE

Usable open space is intended to provide outdoor space for the recreational and leisure time use of, and in close proximity to, the occupants of dwelling units in a residential development with three or more dwelling units.

9.3.5.2 AMOUNT OF USABLE OPEN SPACE REQUIRED

The minimum amount of usable open space provided shall be as set forth in the schedule in subsection 9.2.7.

9.3.5.3 QUALIFYING USABLE OPEN SPACE

To qualify as usable open space, an area shall conform to the following standards:

USABILITY

The area must have a surface that is adequately drained, and permits recreational or leisure time use. Such surface may include any combination of grass, plant materials, wood, or paving materials of a type designed for pedestrian or recreational use. No open space shall be considered usable if:

the slope of the finished grade is more than 10 percent, or

the land does not meet the requirements for developable site area as that term is defined in paragraph 7.9.1.

b. LOCATION

The nearest part of the area shall be not more than 300 feet walking distance from the dwelling unit it serves. Usable open space may be located in an area which:

is on a privately owned lot, or a space designated for the exclusive use of one dwelling unit, or

qualifies as common open space as provided in paragraph 9.3.4.

c. SIZE AND SHAPE

It has a minimum horizontal area of 600 square feet and no dimension is less than 20 feet.

d. STRUCTURES AND FACILITIES

It shall be open to the sky, and may include unroofed facilities such as a tennis court, swimming pool or similar open air recreational facilities. Accessory structures related to such unroofed facilities may be located within the area.

e. ACCESS

The access to usable open space shall conform to the same standards set forth in a. above, but may have dimensions smaller than those set forth in c. above. If the dimensions of the access are smaller than those required in c. above, the access shall not be counted toward the minimum usable open space required in 9.2.7.

9.3.5.4 RELATIONSHIP BETWEEN USABLE AND COMMON OPEN SPACE

Common open space will qualify as usable open space provided it meets the criteria set forth in paragraph 9.3.5.3. Usable open space will qualify as common open space provided it is not on a privately owned lot, or on a space designated for the exclusive use of one dwelling unit.

9.3.6 STREETS, DRIVES

9.3.6.1 OBJECTIVE

The objective of this section is that adequate access for fire-fighting, medical and other emergency operations be provided from the public street system to each development with three or more dwelling units.

9.3.6.2 CONNECTION TO PUBLIC STREET SYSTEM

Each street (See Definition.) and interior drive (See Definition.), or system of streets or interior drives, within a residential development with three or more dwelling units shall connect to a public street.

9.3.6.3 MEANING OF "DEAD-END" STREET

A dead-end street or dead-end interior drive is one which has only one means of entrance and exit to a through public street. (See Definition of THROUGH STREET.)

9.3.6.4 LENGTH, MEASUREMENT OF DEAD-END STREET

A dead-end street or dead-end interior drive shall not extend more than 650 feet from:

a through public street, or

a street or interior drive that intersects with a through public street in at least two places that are not less than 125 feet apart provided such street or interior drive is constructed in accordance with the standards for streets and rights-of-way set forth in the Subdivision Regulations,

The length of a dead-end street or dead-end interior drive and the distance between the intersection of streets shall be measured as described further in the Planning Board's Subdivision Regulations.

In the case where an existing through street connects to another public street in two places but that public street is itself a dead-end street, the through street shall be considered to be a dead-end street.

9.3.6.5 TWO MEANS OF ACCESS

Where there are more than 10 dwellings in a cluster subdivision or a special residential development or more than 20 dwelling units in an RD, Planned Residential Development, district served by a dead-end street or dead-end interior drive, two means of access connected to the public street system, suitable for fire-fighting, medical and other emergency vehicles, shall be provided to each dwelling or dwelling unit. One means of access shall be a street or interior drive that complies with the standards for streets and rights-of-way set forth in the Subdivision Regulations. If not another street, the second means of access may be a paved way, subject to the approval of the Fire Chief, that:

is at least 10 feet wide, and constructed in a manner suitable for fire-fighting equipment,

has provision for snow removal and other maintenance to assure year round access, and

may have a gate or other barrier to restrict general motor vehicle traffic provided there is an easy means of opening such gate or barrier for emergency vehicles.

9.3.6.6 MINIMUM YARD FOR STREET OR INTERIOR DRIVE IN RD DISTRICT

If a street or interior drive in an RD, Planned Residential District, is located in a minimum yard required by 9.2.4, there shall be a screen of densely planted vegetation and/or an opaque fence adjacent to the lot line, as provided in Section 10 of this By-Law, for such distance as the Planning Board may determine in order to provide protection for abutting residential lots.

9.3.7 ACCESSORY APARTMENT

An accessory apartment, as described in subsection 5.2 of this By-Law, may be created in a detached, one-family dwelling in a residential development with three or more dwelling units. In general the provisions of subsections 5.2.1 through 5.2.4 of this By-Law shall apply, with the following exceptions:

the lot area in a conventional subdivision shall be at least the minimum required by Table 2, Schedule of Dimensional Controls, for the zoning district in which the lot is located. (See also paragraph 9.4.3. which requires a greater lot area for larger houses.) The lot area in a cluster subdivision, a special residential development or a development with significant public benefit may be such size as the SPGA may approve;

the dwelling may be newly constructed and does not need to have been constructed by January 1, 1983;

the maximum floor area of the accessory apartment shall be:

1) not more than 1,200 square feet, or

2) not more than 30 percent of the living area of the dwelling,

whichever is less.

paragraph 5.2.2.b.2, which prohibits enlargement of existing dwellings, shall not apply.

9.3.8 EQUIVALENT DENSITY

The maximum density of a facility permitted by 9.2.2 h, i, k, 1, or m. in which living units or other accommodations are not dwelling units, (See Definition.) shall be determined by paragraph 9.2.9 Equivalent Density.

9.4 CONVENTIONAL SUBDIVISION

9.4.1 MEANING OF "CONVENTIONAL SUBDIVISION"

A conventional subdivision is a residential development with three or more dwelling units in which a tract of land is divided into lots for constructing single family detached dwellings. (See also the Definition, Conventional Subdivision.)

9.4.2 DIMENSIONAL STANDARDS

A conventional subdivision shall comply with the applicable dimensional standards set forth in subsection 9.2 and elsewhere in Section 9 for the residential development as a whole. Each lot created within a conventional subdivision must comply with the dimensional standards set forth in Table 2 and elsewhere in this By-Law.

9.4.3 ACCESSORY APARTMENT

If an accessory apartment is included in a dwelling, as provided in paragraph 9.3.7, and if the dwelling has a gross floor area that is 6,200 square feet or more, the minimum lot area shall be 20,000 square feet in the RS district and 35,000 square feet in the RO district. If the dwelling in which the accessory apartment is included has a gross floor area that is less than 6,200 square feet, the minimum lot area shall be 15,500 square feet in the RS district and 30,000 square feet in the RO district.

9.4.4 ADDITIONAL STANDARDS APPLICABLE TO CONVENTIONAL SUBDIVISIONS

In addition to the dimensional standards set forth in subsection 9.2 that apply to a residential development as a whole, the following shall also apply to an individual lot in a conventional subdivision approved after May 4, 1987:

RS, RT DISTRICTRO DISTRICTa.Maximum Impervious Surface Ratio0.200.12and if a dwelling, including any addition thereto, which has a gross floor area of 2500 square feet or more, is erected thereon, it shall have:b.Minimum Side Yard25 feet25 feetMinimum Rear Yard25 feet25 feet

(See also subparagraph 7.2.3 which requires that a minimum percentage of the required minimum lot area be in a contiguous developable site area.)

9.5 CLUSTER SUBDIVISION, SPECIAL RESIDENTIAL DEVELOPMENT

9.5.1 MEANING OF TERMS

A "cluster subdivision" is a residential development with three or more dwelling units in which a tract of land is divided into: 1) lots for constructing dwellings in one or more groups and 2) common open space. The common open space may be in one or more locations and may separate groups of dwellings from each other. (See also the Definition, Cluster Subdivision.)

A "special residential development" is a residential development with three or more dwelling units in which a tract of land is divided into: 1) one or more lots for constructing dwellings in one or more groups and 2) common open space. A "special residential development" may have one or more lots used for developments in:

condominium ownership,

cooperative ownership, or

one ownership where individual dwelling units are rented.

A "special residential development" is intended to provide greater flexibility than a cluster subdivision to respond to special site or development considerations.

9.5.2 OBJECTIVES

The objectives of this section are to allow flexibility in the standards and procedures for residential development with three or more dwelling units that are a cluster subdivision or a special residential development to:

promote development proposals based on an evaluation of the characteristics of individual sites that is difficult to achieve by applying pre-determined, largely geometric standards;

promote the retention and enhancement of the outstanding natural features of open land and of existing man made enhancements to it;

promote an improved design relationship between new buildings and public facilities and common open space;

permit approval of a development based on an evaluation of the projected impacts of the development.

9.5.3 MAXIMUM DEVELOPMENT BASED ON IMPACT

9.5.3.1 OBJECTIVE

The objective of this section, and of section 9.6. Developments with Significant Public Benefit, is to base the amount of development allowed on the projected impacts of the development on the adjacent neighborhood and municipal facilities and services.

9.5.3.2 MAXIMUM DEVELOPMENT BASED ON IMPACT

The projected impacts of a cluster subdivision or a special residential development shall not be greater than the total projected impacts of one-family detached dwellings that could be constructed on individual lots in a conventional subdivision on the tract according to the procedure described in this section. The maximum development permitted in a cluster or special residential development may not exceed ANY of the total impacts that are projected to occur from such one-family detached dwellings based on the following impact measures each considered separately:

Gross Floor Area of Dwelling Units

Living Area of Dwelling Units

Site Coverage of Dwelling Units

Total Number of Occupants of Dwelling Units

Vehicular Trip Generation from Dwelling Units

The maximum development permitted is not to be based on the number of dwelling units. The number of dwelling units permitted is not predetermined; it is the number that occurs in a development when none of the impact measures, each considered separately, exceeds the total impact that is projected to occur in a conventional subdivision on the tract according to the procedure described in this section.

9.5.3.3 NO ENTITLEMENT TO MAXIMUM DEVELOPMENT

An applicant is not entitled to the maximum development described in paragraph 9.5.3.2 nor is the applicant entitled to approval of a cluster subdivision or special residential development. The amount of development permitted, as calculated by any of the impact measures, will be based on the Planning Board's evaluation of the proposed development and the extent to which it complies with the criteria set forth in paragraph 9.5.5.

9.5.4 CALCULATION OF IMPACT OF DEVELOPMENT

9.5.4.1 MEASURES OF THE IMPACT OF DWELLING UNITS

For the purpose of the calculations required elsewhere in this section, the impact of a one-family detached dwelling constructed on a lot in a conventional subdivision is determined to be:

a. Gross Floor Area of One-family Dwelling Unit: 7,200 square feet;

b. Living Area of One-family Dwelling Unit: 4,700 square feet;

c. Site Coverage of One-family Dwelling Unit: 2,900 square feet;

d. Total Number of Occupants of One-family Dwelling Unit: 5 persons

e. Number of Vehicle Trips Generated by a One-family Dwelling Unit: 15 trips

9.5.4.2 IMPACTS OF OTHER TYPES OF DWELLING UNITS

The Planning Board shall periodically publish the projected total number of occupants in, and the number of motor vehicle trips generated by, other types of dwelling units. Those other types of dwelling units shall include:

a. One-family Detached*,

b. One-family Attached*,

c. Two-family*, and

d. Townhouse*.

* (See definition in Section 2.)

The Planning Board shall periodically tabulate and publish data on such other types of dwelling units:

that have been constructed in the preceding 10 years, or

on the 25 most recently constructed dwelling units of that type,

whichever results in the greater number of dwelling units in the sample.

In estimating the projected total number of occupants in, and the number of vehicular trips generated by, other types of dwelling units, the Planning Board shall consider the size of the dwelling units, the number of bedrooms and other physical and economic characteristics of the dwelling units. In projecting:

the total number of occupants in other types of dwellings, the Planning Board shall consider data reported in the Town Census conducted by the Town Clerk in the most recent calendar year;

the total number of vehicle trips, the Planning Board shall use the estimates of trip generation outlined in paragraph 12.2.4.a, trip generation, of this By-Law.

9.5.4.3 CALCULATION OF MAXIMUM DEVELOPMENT

The maximum development permitted in a cluster or special residential development shall be determined by using the following procedure:

STEP ONE:

calculate the maximum number of dwellings in a conventional subdivision by the following formula:

divide the area of the lot by the minimum lot area for the district in which the lot is located (RO=30,000 s.f., RS and RT=15,500 s.f.) provided any fraction thereof may be included in the calculation;

STEP TWO

calculate the total gross floor area of all dwellings in a cluster or special residential development by multiplying 7,200 square feet by the maximum number of dwellings in a conventional subdivision in 1) above;

calculate the total living area of all dwellings in a cluster or special residential development by multiplying 4,700 square feet by the maximum number of dwellings in a conventional subdivision in 1) above;

calculate the total site coverage of all dwellings in a cluster or special residential development by multiplying 2,900 square feet by the maximum number of dwellings in a conventional subdivision in 1) above;

STEP THREE

calculate the projected total number of occupants of all dwellings in a cluster or special residential development by multiplying five persons by the maximum number of dwellings in a conventional subdivision in 1) above.

To determine the projected number of total occupants of "other types of dwelling units" (9.5.4.2), the applicant shall furnish a schedule showing the number of proposed dwelling units, according to:

the type of structure,

the number of bedrooms,

the living area, and

the projected rent or sales price

of each proposed dwelling unit.

Based on the data available to it, as described in paragraph 9.5.4.2, the Planning Board shall determine the projected total number of occupants in "other types of dwelling units" referred to in paragraph 9.5.4.2 that corresponds most closely to the schedule furnished by the applicant. The projected total number of occupants shall be the median in the data range.

STEP FOUR

Calculate the projected total number of vehicle trips generated from all dwellings in a cluster or special residential development by multiplying 15 vehicles times the maximum number of dwellings in a conventional subdivision. (See 1) above.)

Based on the schedule furnished by the applicant, described in 5) a. and b. above, and on the data available to it, as described in paragraph 9.5.4.2, the Planning Board shall estimate the total number of vehicle trips generated from the "other types of dwellings" referred to in paragraph 9.5.4.2 that corresponds most closely to the schedule furnished by the applicant.

This worksheet is for illustrative purposes only. It is not legally adopted

by the Town Meeting as a part of the Zoning Bylaw.

WORKSHEET FOR CALCULATION OF

PARAGRAPH 9.5.4.3 CALCULATION OF MAXIMUM DEVELOPMENT

STEP ONE(1)

Area of the lot

_________________(2)

Divide (1) by minimum lot area for the district (RO=30,000 sf, RS and RT=15,500 sf)(3)

__________

Maximum number of dwellings

in a conventional developmentSTEP TWOTotal gross floor area of all dwellings7,200 square feet X__________

(3)= ___________

Square FeetTotal living area

of all dwellings4,700 square feet X__________

(3)= ___________

Square FeetTotal site coverage

of all dwellings2,900 square feet X__________

(3)= ___________

Square FeetSTEP THREEProjected total number of occupants of all dwellings5 persons X__________

(3)= _______

PersonsSTEP FOURProjected total number of vehicle trips generated

from all dwellings15 trips X__________

(3)= _______

Vehicular trips

For assistance in determining the estimated occupancy of other types of housing, contact the Planning Department.

9.5.4.4 EFFECT OF IMPACT MEASURES ON AN APPROVED DEVELOPMENT

a. OCCUPANCY AND NUMBER OF MOTOR VEHICLE TRIPS: The calculation of impact measures for occupancy and number of motor vehicle trips is only for the purposes of estimating impacts for approval of a development application. The median of the population and motor vehicle trip generation data series, as described in paragraphs 9.5.4.2 and 9.5.4.3, is determined to be an adequate measure of the impact of a typical dwelling unit. This method of estimating impacts assumes that the actual occupancy, either initially or later, of any one dwelling unit may be higher or lower than the typical dwelling unit used in these calculations. Neither the initial occupancy nor any change in the later occupancy of, or the number of motor vehicle trips generated from, any dwelling unit, shall affect the occupancy or limit the ownership or use of motor vehicles in that dwelling unit.

b. GROSS FLOOR AREA, LIVING AREA, SITE COVERAGE: The total gross floor area, living area, site coverage of all dwellings, as determined by the calculation of impact measures in paragraph 9.5.4.3, is the maximum for approved development. After the granting of a special permit approving the development, no building permit shall be issued for any dwelling that would result in the maximum specified in the approval being exceeded.

9.5.5 CRITERIA FOR APPROVAL

Prior to the approval of a cluster subdivision or a special residential development, in addition to the findings and determinations required by paragraph 3.4.2 of this By-Law, the Planning Board shall determine that the proposed development meets the following criteria:

the common open space includes:

some, or all, of the outstanding natural features of the site and of the man made features, such as but not limited to stone walls, that enhance the land form;

land that also meets the standards for usable open space;

land that increases visual amenities for residents of the development and of the adjacent neighborhood;

the common open space is readily accessible by one or more paths or entry points specifically designed for access purposes;

the dwellings are sited and oriented in a complementary relationship to:

each other,

the common open space, and

the adjacent properties. If the development includes other types of dwellings, such as semi-attached dwellings or townhouses, those types of dwellings shall relate to the predominant characteristics of the adjacent one-family detached dwellings with respect to scale, mass, setback, proportions and materials;

negative visual impacts of the development, if any, are screened from adjacent properties and nearby streets by landscaping or other site planning techniques;

where opportunities exist, improved access is provided to, or additional links and connections are developed to, a town system of public facilities, such as open space, recreation facilities, footpaths or bicycle paths;

that any building which contains more than one dwelling unit is designed so that either:

the building has the exterior appearance of a one-family dwelling or,

alternatively, if one-family attached dwellings and/or townhouses (See 9.2.2b. or e. and the definitions of those terms under "Dwelling, Structural Characteristics" in Section 2, Definitions.) are constructed, each individual dwelling unit has direct access to ground level and an opportunity for a private yard, patio, or other private outdoor space;

there are provisions for common facilities, such as recreation or parking, or for services such as the maintenance of streets, walkways or paths, utilities, landscaping or recreation facilities;

where there are sufficient dwellings units, the layout of the street(s) and interior drive(s) will accommodate vehicles, other than automobiles, that are used in local transportation services.

9.5.6 SPECIAL PERMITS, DIMENSIONAL STANDARDS, WAIVERS, TYPES OF HOUSING

The Planning Board, acting as SPGA, may, as part of the grant of a special permit with site plan review, also grant a special permit to:

a. modify the standards:

in Table 2, Schedule of Dimensional Controls, for minimum lot area, minimum lot frontage, minimum front yard, minimum side yard, minimum rear yard, maximum percentage of site coverage, and maximum height in stories;

the provisions of 7.1.4 relative to the number of dwellings on a lot;

the minimum lot width in subsection 7.2.2;

the provisions in subsection 7.2.3 relative to contiguous developable site area;

in subparagraph 11.4.1 relative to the location of off-street parking spaces;

in subsection 11.6 relative to setbacks required for parking spaces and driveways; and

in subparagraph 6.2.5 relative to the subdivision of land in relation to lots or buildings that are nonconforming or would not comply with this By-Law as a result of the proposed development;

all as they may apply to individual dwellings or lots within a cluster subdivision or a special residential development:

b. permit the types of buildings identified in 9.2.2 as allowed by special permit;

c. allow an existing structure, that was constructed at least 10 years prior to the date of application for approval of the special permit, to be converted to a three-, or four-family dwelling, a multi-family dwelling, a rooming house, a group quarters, an independent living residence, an assisted living residence, or a congregate living facility, provided the Planning Board determines that:

the structure can be modified for a residential use that does not have adverse impacts on the adjacent single family neighborhood;

the exterior character of the structure is maintained and is compatible with the adjacent neighborhood of single-family dwellings;

modification of the existing structure maintains more of the site open than the alternative of removal of the structure and further subdivision of the lot into house lots;

d. allow a driveway on one lot to lead to a parking space on another lot, or to allow a driveway to straddle a lot line, as provided in paragraph 11.8.c.

9.5.7 COMMON OPEN SPACE

In granting a special permit with site plan review for a special residential development, the Planning Board may require a greater amount of common space than the minimum 10 per cent required by line 9.2.6. In making that determination, the Planning Board shall consider the need to protect the natural features of the site, the type of housing to be constructed and its relationship to common open space, and potential public access to and use of the open space.

9.5.8 ACCESSORY APARTMENT IN CLUSTER SUBDIVISION, SPECIAL RESIDENTIAL DEVELOPMENT

If an accessory apartment is included in a dwelling, as provided in paragraph 9.3.7, in a cluster subdivision or special residential development, it shall be considered to be one of the other types of dwelling units and included in the calculation of the maximum development permitted based on the various impact measures. (See subsection 9.5.4.3.)

9.6 DEVELOPMENTS WITH SIGNIFICANT PUBLIC BENEFIT (DSPB)

9.6.1 MEANING OF TERM

A development with significant public benefit (DSPB) is a cluster subdivision or a special residential development (See subsection 9.5.) in which the Planning Board has determined that there are sufficient benefits to the adjacent neighborhood and the town generally to warrant an increase in the maximum development permitted.

9.6.2 OBJECTIVES

The objectives of this section are to allow additional flexibility in the standards and procedures for approval and to provide incentives for applicants to propose a development with significant public benefit and to:

encourage the provision of more public facilities and services that benefit the adjacent neighborhood and the town generally;

encourage types of housing that meet the needs of age groups, income groups, or persons with special needs, that are not adequately served by large single family dwellings;

encourage a greater degree of review of the design features of a residential development;

require a higher qualitative standard:

of building design, and

in the provision of public facilities and the provision of open space;

further the objectives set forth in paragraph 9.1.1;

than would otherwise apply in the administration of zoning and subdivision regulations.

9.6.3 MAXIMUM DEVELOPMENT

9.6.3.1 MAXIMUM DEVELOPMENT INCENTIVE

The maximum development permitted in a development with significant public benefit may not exceed that permitted in a cluster or special residential development (See subsection 9.5.4.2.) by more than 25 percent for ANY of the following impact measures each considered separately:

a. Gross Floor Area of Dwelling Units

b. Living Area of Dwelling Units

c. Site Coverage of Dwelling Units

d. Total Number of Occupants of Dwelling Units

e. Vehicular Trip Generation from Dwelling Units

9.6.3.2 NO ENTITLEMENT TO MAXIMUM DEVELOPMENT INCENTIVE

An applicant is not entitled to the maximum development described in paragraph 9.6.3.1. The amount of development permitted, as calculated by any of the impact measures, will be based on the Planning Board's evaluation of the proposed development and the extent to which it complies with the criteria set forth in paragraph

9.6.4 SIGNIFICANT PUBLIC BENEFIT DEFINED

9.6.4.1 QUALIFYING SIGNIFICANT PUBLIC BENEFIT

A significant public benefit shall be a benefit to the adjacent neighborhood and the town generally as determined by the Planning Board. In general a qualifying public benefit shall be:

improvements in the adjacent neighborhood similar to the required improvements on the site - such required improvements being those identified elsewhere in this By-Law or in subsection 3.6 of the Subdivision Regulations, such as, but not limited to, any facility, infrastructure, or restriction on the development of land in relationship to the development of land and buildings;

improvements on the site that are, in the opinion of the Planning Board, well in excess of those otherwise required;

restrictions on, or special design or development features of, uses and buildings permitted in the zoning district.

A significant public benefit may be one or more of the following as determined by the Planning Board after consultation with the board, committee, commission, department or official indicated and such others as the Planning Board may determine:

preservation of a historic structure or place - with the Historical Commission and, as applicable, the Historic Districts Commission;

protection of open land that is dry and otherwise developable, and potentially an important addition to the inventory of open space in the town - with the Conservation Commission and the Recreation Committee. All of such open land shall be accessible to the public. The type of private homeowners association reserve, allowed in 9.3.4.3 2), from which the public could be excluded, shall not qualify;

provision of public recreation facilities - with the Recreation Committee;

installation of paths to provide pedestrian and bicycle access to open space or other public facilities in the adjacent neighborhood - with the Recreation Committee, the Bicycle Advisory Committee and the Conservation Commission;

installation of street trees or other landscaping features within the right of way of a public street, or a street previously approved under the Subdivision Regulations, - with the Superintendent of Parks and Trees;

placement underground of electric power lines and communication lines, such as, but not limited to telephone, security alarm and cable TV lines - with the Town Engineer;

provision of housing units for low- and moderate-income households - with LEXHAB or the Lexington Housing Authority, and as applicable, the Human Services Committee or the Council on Aging;

provision of housing units that, upon initial occupancy would cost more than low- and moderate-income households could afford but, due to deed restrictions or other legally binding restrictions: 1) could be afforded by households whose annual income is not greater than the median income for the Boston Metropolitan Area, and 2) are projected to be affordable by low- and moderate-income households within 15 years - with LEXHAB or the Lexington Housing Authority;

provision of housing units that are of a size or type that meet the needs of segments of the town's population that, due to age or special needs, are not adequately served by large single family dwellings - with LEXHAB or the Lexington Housing Authority, and as applicable, the Human Services Committee or the Council on Aging;

provision of facilities for alternate transportation services that do not rely on the use of single occupant automobiles - with the Transportation Advisory Committee. The alternate transportation services may include a financial contribution to a service provided by the Town of Lexington, or a service provided by others and coordinated by the Town;

provision of transportation facilities, such as a walk, or path, or traffic engineering improvements - with the Town Engineer, the Transportation Advisory Committee, the Recreation Committee or the Bicycle Advisory Committee;

provision of a utility or underground facility, including but not limited to water service, sanitary sewer service, storm water management systems, or the expansion in the capacity of an existing facility or system - with the Town Engineer.

9.6.4.2 IMPROVEMENTS BENEFITING ADJACENT NEIGHBORHOOD

Qualifying improvements shall generally include those that benefit the adjacent neighborhood or are provided on the site. If the Planning Board first determines that the type of improvements listed in 9.6.4.1. are not needed or cannot be provided in the adjacent neighborhood, or on the site, the Planning Board may consider instead a financial contribution to one or more Town funds established for the purposes listed in 9.6.4.1.

9.6.4.3 IMPROVEMENTS NOT QUALIFYING AS SIGNIFICANT PUBLIC BENEFIT

A significant public benefit shall not include any required improvement identified elsewhere in this By-Law or in subsection 3.6 of the Subdivision Regulations, such as, but not limited to, any facility, infrastructure, or restriction on the development of land in relationship to the development of land and buildings. A waiver from the requirements of the Subdivision Regulations or of the usual requirements of this By-Law for a conventional subdivision shall not be considered to be a significant public benefit.

9.6.5 CRITERIA FOR APPROVAL

Prior to the approval of a development with a significant public benefit, the Planning Board shall determine, in addition to the findings and determinations required by paragraph 3.4.2 of this By-Law, and paragraph 9.5.5, criteria for approval of a cluster subdivision or a special residential development, that the proposed development meets the following criteria:

that there are sufficient benefits to the adjacent neighborhood and the town generally to warrant an increase in the maximum development permitted; and

that legally binding documents have been submitted to ensure the completion and continued availability of any proposed improvement or special condition that qualifies as a significant public benefit.

9.6.6 SPECIAL PERMITS, TYPES OF HOUSING, DIMENSIONAL STANDARDS, WAIVERS

The Planning Board, acting as SPGA, and as part of the grant of a special permit with site plan review to approve a development with significant public benefit, may also grant any of the special permits described in subparagraph 9.5.6.

9.6.7 COMMON OPEN SPACE

The public shall have access to all common open space in a development with significant public benefit. The provisions of paragraph 9.3.4.3 2) that allow common open space in a cluster subdivision or a special residential development to be owned by a legal association comprised of the owners of the development, which may exclude the public, shall not apply in a development with significant public benefit.

9.7 SPECIAL PERMITS: PROCEDURES. CRITERIA

9.7.1 SPS REQUIRED

No residential development with three or more dwelling units shall be initiated without first obtaining a special permit with site plan review in accordance with the provisions of this section. The purpose of the special permit with site plan review is to provide detailed review of residential developments with three or more dwelling units which have a substantial impact upon the character of the town, adjacent residential areas and the provision of public facilities and services.

9.7.2 SPGA

The Planning Board shall be the Special Permit Granting Authority for all residential development with three or more dwelling units except for a development in an RD district and for the conversion of a municipal building. (See subsection 8.3.4 for a development in an RD district, where the Board of Appeals is the SPGA; see subsection 9.8 for conversion of a municipal building, where the Board of Selectmen is the SPGA.) In acting upon applications for special permits with site plan review, the SPGA shall be governed by the provisions of Sections 3.4 and 3.5.

9.7.3 SPECIAL PERMIT APPLICATION REQUIREMENTS

The application to the SPGA for a special permit with site plan review (SPS) under this section shall be accompanied by a definitive site development plan, as described in subsection 3.6 and where the Planning Board is the SPGA, as the Planning Board may describe in its Development Regulations.

Where the applicant submits a definitive subdivision plan complying with the Subdivision Control Law and the Planning Board's "Development Regulations", insofar as practical, the public hearing on the application for the special permit with site plan review and the definitive subdivision plan shall be held concurrently.

9.7.4 SPECIAL PERMIT PROVISIONS

In addition to the conditions cited in paragraph 3.4.3, the SPGA may grant a special permit with site plan review for the development of a tract of land in a residential district provided it makes a determination that the proposed development is consistent with the standards and criteria set forth in subsection 9.5.5 and 9.6.5, subject to the following provisions:

the special permit shall incorporate by reference the building design and definitive site development plans filed with the application for a special permit;

that, where applicable, the special permit shall incorporate by reference, any legally binding document that has been submitted to ensure the completion and continued availability of any proposed improvement or special condition;

The SPGA may require that the amount of development be less than that shown on the definitive site development plan if it determines that the criteria contained in subsections 9.5.5 or 9.6.5 so require.

9.7.5 DENIAL OF SPECIAL PERMIT

The SPGA may deny an application for a special permit with site plan review hereunder and base its denial upon:

a failure to comply with the provisions set forth in Section 9, or

a finding that the proposed development would not be consistent with the general objectives for planned residential development set forth in subsection 9.1.1, or the criteria set forth in subsections 9.5.5 or 9.6.5.

9.7.6 REVISION OF SPECIAL PERMIT

Subsequent to a special permit with site plan review granted by the SPGA under the provisions of this section, minor revisions may be made from time to time in accordance with applicable law, by-laws, and regulations, but the residential development with three or more dwelling units approved under such SPS shall otherwise be constructed in accordance with the approved definitive site development plan. The developer shall notify the SPGA in advance of any such revision which shall not be effective until approved by vote of the SPGA. If the SPGA determines such revisions not to be minor, it shall order that an application for a revised SPS be filed, and a public hearing be held in the same manner as set forth in Section 3.5.

9.8 CONVERSION OF MUNICIPAL BUILDINGS AND SURPLUS MUNICIPAL LAND

9.8.1 GENERAL OBJECTIVES

This section is intended to allow the conversion of municipal buildings and the development of land on which they are situated and of surplus municipal land in a manner which:

encourages practical residential development in the reuse of existing structures;

is compatible with the adjacent neighborhood;

encourages development of economically priced housing and a variety of types of housing; and

fosters flexibility and creativity in the disposition of surplus municipal property.

9.8.2 MODIFIED RD PROCEDURE

The conversion of a municipal building or the development of surplus municipal land shall follow the same procedures for the rezoning of land for the RD, Planned Residential Development, district with the following exceptions:

the minimum size of the RD, Planned Residential Development, district and Minimum Area of the Tract to be Developed specified in line 9.2.1 and in Table 2 may be less than 125,000 square feet; and

the Minimum Frontage of the Tract on An Existing Street specified in line 9.2.3 and in Table 2 may be less than 100 feet.

9.8.3 SPGA

The Board of Selectmen shall be the Special Permit Granting Authority.

There was discussion at public meetings as to whether the formula and procedures in the amendment will result in a cluster subdivision that is directly comparable to a conventional subdivision. There is an incentive built into the formula for calculating maximum developments based on the area of the lot only. That is offset by the fact that the range is a five year period. If the range were limited to the last two years, huge houses constructed recently in the 9,200 - 10,500 square foot range would skew the 75th percentile upward.

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