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Smart Growth / Smart Energy Toolkit Modules - Zoning Decisions

Learn about the Smart Growth/Smart Energy Zoning Decisions module.


Communities in Massachusetts that are looking to implement various smart growth/smart energy measures must often consider changes to the local Zoning Bylaw (in a town or an ordinance in a city) to enable or require improved patterns of development. Once a community has identified which tools are suitable to its goals, it must decide how to frame those tools within its regulatory approach. The Massachusetts statutes and a lengthy body of land use case law provide for a variety of zoning approaches that have different advantages depending upon a community's goals, administrative capacity, and existing zoning framework.


Once a community has drafted a Comprehensive Plan, an Affordable Housing Plan, or developed a Vision Plan for a particular neighborhood, municipal officials must decide how to incorporate desired land use changes into their local bylaws, ordinances, and/or regulations. To choose the right regulatory approach, planners need to ask a series of critical questions including:

  • What are the different enforcement mechanisms associated with different zoning approaches and how much "teeth" do they give local officials?
  • How can bylaws, ordinances, or regulations achieve our environmental, economic, and housing goals?
  • How much capacity do we have to administer a more complex permitting process?
  • What is necessary to ensure the acceptance of these regulatory tools by Town Meeting voters or City Council members?
  • Are the bylaws, ordinances, and regulations going to be more prescriptive or proscriptive?
  • Does the existing zoning in our target area meet our goals ? if not, what are all the options we might consider (e.g., multiple districts)?
  • Will the permitting standards be flexible and encourage developers to work with the municipality and community?
  • Are we considering providing incentives or bonuses to applicants and what do we want to achieve from them? What are the pros and cons of each incentive or bonus?

These and other questions will help communities gradually identify the appropriate mechanism(s) to apply to their new regulatory approach.


Zoning is a legislative method for controlling land uses in the United States. It began as a method for maintaining the character of an area, protecting it against inappropriate siting of industrial uses, and eliminating substandard housing conditions in many densely developed areas. This notion was upheld by the Supreme Court as an accepted extension of municipal police powers (Village of Euclid, Ohio v. Ambler Realty Co.); to promote the public health, morals, or safety, and the general well-being of a community. The outcome of this landmark court case is what is now referred to as "Euclidean Zoning" , currently the most common form of zoning in the U.S. This form of zoning typically specifies where certain types of land uses, such as residential, industrial, or commercial activities, can take place in a community. Although this type of zoning is effective and easy to implement, its rigid nature has created neighborhoods that are auto-dependent and, in many ways, unsustainable.

  • Euclidean Zoning results in undesirable patterns of land use that have earned many neighborhoods the label "unsustainable". In the context of zoning that induces sprawl, the term "unsustainable" reflects:
    • Communities or neighborhoods in which automobile travel is necessary to obtain the most basic goods and services;
    • Street design that reflects a focus on automotive travel and very few pedestrian or bicycle amenities exist;
    • Sprawling development patterns that create far more infrastructure than what would be required in more compact developments resulting in strained fiscal resources;
    • The widespread development of pavement and lawns that have a seriously damaging effect on the environment; and
    • Homogenous design in housing stock and commercial use, which compromises a community's ability to compete in the regional economy.

What many communities in Massachusetts are now realizing is that the more innovative approaches to development such as Transfer of Development Rights (TDR), Open Space Residential Design (OSRD), and Traditional Neighborhood Development (TND) may be difficult to fit within the rigid structure of their Zoning Bylaw or Ordinance.

Permitting approaches such as Special Permits, Overlay Districts, and Site Plan Review can allow for smart growth, but must be considered carefully so they can be best suited to the distinctiveness of each municipality. Subtle differences in how these approaches are administered, reviewed, and enforced can significantly affect whether or not a community achieves the smart growth/smart energy objectives it has in mind.

Amending Zoning Bylaws/Ordinances and Maps

These rules and procedures are an essential backdrop to any re-zoning effort. Local boards or citizens who wish to propose a zoning amendment must plan carefully in order to comply with several statutory guidelines throughout the process. According to the Zoning Act (M.G.L. Chapter 40A), zoning codes must be approved by the local legislative body by a supermajority vote (2/3 vote) and in some municipalities by a 3/4 vote if a written protest has been filed. The basic steps for adopting a new or revised zoning bylaw or ordinance are as follows:

  1. Initiation by a City Council, Board of Selectmen, Zoning Board, an individual who owns land that would be affected by the proposal, regional planning entity, registered voters (pursuant to M.G.L. Chapter 39, Section 10: Warrant; issuance; contents), ten registered voters in a City or by other methods provided by municipal charter.
  2. Within fourteen days of receipt, the Board of Selectmen or City Council submits the ordinance or bylaw to the Planning Board for review.
  3. The Planning Board or City Council must hold a public hearing within 65 days of receipt of the proposed ordinance or bylaw.
  4. Notice of the public hearing must be published in the local newspaper for two successive weeks and posted in the Town or City Hall. The first notice must be published 14 days before the hearing. The time, date, and place of the public hearing, its subject matter, and the location where the text and map can be inspected must be included in the notice.
  5. The Massachusetts Department of Housing and Community Development, the appropriate Regional Planning Agency, and abutting planning boards should be notified. However, these parties may waive their right to a notice.
  6. The bylaw or ordinance must also be approved by the Massachusetts Attorney General’s Office prior to adoption by the town as required by Massachusetts General Law (M.G.L. Chapter 40, Section 32). The Planning Board must submit the bylaw or ordinance along with a statement explaining the contents or amendments proposed, with explanatory maps or plans if appropriate.

Once a zoning bylaw has been adopted or amended, boards and departments should incorporate consistent standards into their accompanying zoning rules and regulations. Even if they are not the permitting authority, all boards and departments should evaluate their regulations to ensure that there is no conflict with the newly adopted bylaw. For example, design standards for Site Plan Review and Special Permitting should be complementary, not contradictory, to community goals described in local plans.


The Basics of By-Right Permitting

The term "by-right" or "as-of-right", which is often used in planning and zoning terminology, refers to land uses that are allowed in a particular district without discretionary review. While these developments must abide by other local and state regulations such as environmental regulations, and building codes, they cannot be prohibited. The greatest benefit of by-right permitting is that it is the most predictable and easiest permitting method. Therefore, towns may want to permit the types of land uses that they would like to encourage as "by-right" uses, as well as uses that are not likely to have significant impacts on the town or neighborhood. For example, single-family residential homes are typically permitted by-right in multiple districts in most communities.

By-right development is regulated by a city's or town's zoning enforcement agent. In Massachusetts, these responsibilities are commonly administered by the Building Inspector, who may issue building permits based on basic applications to his or her office. If applications are deemed to be in non-compliance with zoning, or if a type of development is typically subject to a higher level of review, the zoning enforcement agent will refer the applicant to the proper authority. For example, if a development requires a variance or a Special Permit, the Building Inspector will refer the applicant to the appropriate permit granting authority.

Applicants that wish to appeal determinations made by the zoning enforcement official do so to the Zoning Board of Appeals through the process outlined in sections 7, 8, and 15 of the State Zoning Act, M.G.L. Chapter 40A. However, it is important to note that the Expedited Permitting Law (M.G.L. Chapter 43D) allows a developer to move forward with a project while a permit is being appealed.

Important Considerations for Local Practitioners

Recent trends toward encouraging smart growth/smart energy in Massachusetts have included a strong emphasis on using the by-right approach to make smart growth/smart energy techniques easier to permit and more attractive to the development community. Historically, zoning standards for by-right uses only included basic use, bulk, and dimensional requirements and did not therefore address better design and smarter patterns of development. More design-oriented zoning tools, housing production tools, or other innovative approaches have typically been implemented through a longer, more discretionary Special Permit process. Although the Special Permit process can have many advantages, the length of permitting, the uncertainty of approval, and the possibility of appeal have often made this approach less attractive to developers.

To avoid losing control over development patterns with a by-right approach, communities need to create detailed and easy-to-follow plans that clearly illustrate the desired outcome for a single-site, a neighborhood, a zoning district, or the community as a whole. Master Plans, Regulating Plans, and Community Visions can serve as the foundation for sophisticated by-right permitting and illustrate to developers what the outcome of their applications should be. While plans and visions are not as binding as zoning in the regulatory sense, they do serve and important role in establishing a clear direction for achieving community goals. Another effective way to maintain the assurances of by-right development while providing a forum for input from local boards is through Site Plan Review. This technique is widely applied throughout Massachusetts and is discussed in more detail in the following section.

To increase the focus on more sophisticated by-right approaches, the Commonwealth has instituted several legislative incentives that foster better "up-front" planning for the purposes of more streamlined and predictable permitting. For example, the Massachusetts Expedited Permitting Law, Chapter 205 of the Acts of 2006 (M.G.L. Chapter 43D) allows communities that accept this new law to designate specific locations in the community as Priority Development Sites, thus providing an incentive for municipalities to allow by-right development in these areas where economic development is desired. Similarly, Chapter 40R provides incentives to communities to codify "Smart Growth Overlay Districts" that include a by-right mix of uses and affordable housing at higher densities.

Site Plan Review

The Basics of Site Plan Review in Massachusetts

Site Plan Review is meant to establish design standards for a development - not the use on a site. For example, site plan approval may establish landscape, stormwater management, parking, and noise level standards for a commercial development. These are clear and fair standards that the developer will address when proposing a project.

Site Plan Review generally describes a coordinated review of a development application between several local agents or boards. This technique is widely applied across Massachusetts and is designed to gather input from various agencies through a prescribed review process. Similar to typical application of a Special Permit process, Site Plan Review is often triggered by certain types of uses (e.g., shared driveways, restaurants, etc.), or certain scales of uses (e.g., commercial uses over 5,000 square feet, subdivisions with more than five lots, etc.)

A typical Site Plan Review bylaw or ordinance requires plans to be distributed to a variety of officials that could include, but is not limited to, the Police and/or Fire Chief, the Planning Board, the Zoning Board of Appeals, the Conservation Commission, the Building Inspector, and the Board of Health. The Planning Board may also adopt regulations for the administration of Site Plan guidelines. Regulations associated with Site Plan Review can include technical requirements for submittals such as traffic analyses or fiscal impact analyses or could also include the details of design guidelines associated with certain areas of a city or town.

These boards and departments are provided the opportunity to comment to the permitting authority within a prescribed period of time. Once the regulatory authority, typically the Planning Board, has reviewed the plans and associated comments, a decision is made and recorded. Similar to a Special Permit, a decision can include approval or approval with conditions. However, the ability of the lead agency to deny the application is limited to the design standards as described below in more detail.

Because Site Plan Review has such potentially wide applicability, many communities have attempted to tailor the requirements to different scales of use. For example, communities have adopted provisions for "Major" and "Minor Site Plan Review" in an effort to relieve some of the permitting burden on smaller projects while still providing an opportunity to obtain necessary information from the developer and to share it with other boards. Major projects generally require the submission of additional information with the Site Plan such as a transportation or stormwater management plan. The threshold for consideration as a major project often includes a change in use, the addition of parking, and if the use is industrial, commercial or multi-family residential. On the other hand, minor projects may be administered by an interagency review but could also be administered exclusively by the Building Inspector and not include a public hearing. These so-called "minor" projects are typically classified as proposals for buildings ranging between 500 to 2,000 square feet. These smaller projects are generally required to provide less information in the application and often enjoy a faster review process. Approval of Site Plans is usually a simple majority vote of the lead reviewing agency.

Typical elements of a Site Plan Review bylaw or ordinance, regardless of the scale of development, include:

  • Applicability (What type of development requires Site Plan Review?)
  • Authority (Who is the lead review agency?)
  • Process (What is the submittal, public hearing, and decision process?)
  • Plan Requirements (What information is needed to make a decision?)
  • Standards (What unique design or use guidelines apply to the use or area?)
  • Findings or Criteria for Approval (How will the permitting authority determine if the site plan will be approved?)
  • Decision (What will the procedure be for issuing and recording a decision?)

Important Considerations for Local Practitioners

Unlike the Special Permit process, Site Plan Review is not specifically addressed in the State Zoning Act but has been upheld by the courts under Home Rule as a reasonable means to review development applications at the local level. Because the process lacks statutory guidelines, communities must carefully consider some fundamental issues before implementing Site Plan Review.

Because the Site Plan Review process can potentially increase the amount and technical nature of information being submitted to local boards, communities must assess their capacity to review and administer these plans before adopting Site Plan Review. Site Plan Review may require technical assistance to the Planning Board from an outside expert to adequately review complex legal or engineering issues. The level of technical data associated with Site Plan Review is a good indicator of whether the process should be associated with by-right or Special Permit applications. For example, if local boards find themselves asking for detailed traffic or drainage data as part of Site Plan Review in a particular district, these officials should consider incorporating a Special Permit process into these districts if one does not already exist. Likewise, if a pattern emerges for a particular use where local boards are regularly asking for technical peer review during Site Plan approval, these uses are probably good candidates for Special Permit applications. A more detailed discussion of Site Plan Review as attached to by-right uses and Special Permit applications follows.

Using Site Plan Review as Part of Special Permit Applications.

Perhaps the most important decision a community must make regarding Site Plan Review is whether the process is tied to by-right uses, those potentially allowed by Special Permit, or both. Many communities fold the Site Plan Review process into the review of Special Permits. This adds the coordinated review of other boards to the Special Permit process with standards for site plan elements (e.g. landscaping, lighting, circulation, façade design, etc.). As with any Special Permit process, appeals of any decision will be made to a court of competent jurisdiction. In using this approach, it is important that not all uses within the zoning district be subject to this type of review. Reasonable uses must be allowed without such review to avoid creating an "all special permit" zoning district. Districts where all development requires a special permit have been determined by the courts to be inconsistent with the State Zoning Act.

Using Site Plan Review for By-Right Uses.

When Site Plan Review is associated with by-right uses, there are a few critical considerations for local permitting authorities. Because the use is by-right, the lead reviewing authority does not have the power to deny the use. The Supreme Judicial Court defined Site Plan Review as "regulation of a use rather than its prohibition..." (Bobrowski 2002). An application can be denied for procedural violations such as submitting incomplete plans or plans that are inconsistent. However, at the end of the process, the use is allowed by-right and therefore cannot be prohibited once the application is complete. In terms of approving with conditions, the reviewing authority may impose reasonable conditions that further the purposes and standards of the zoning code. When an appeal of a denied site plan has reached the court, case law demonstrates that decisions have often favored the applicant. A more detailed discussion of the case law associated with challenges to Site Plan Review can be found in the Handbook of Massachusetts Land Use and Planning Law (Bobrowski 2002).

It is important to note that the use of Site Plan Review for the reasonable regulation of land uses that fall under the "Dover Amendment" (M.G.L. Chapter 40A, Section 3 - including educational, religious and agricultural uses - has not been challenged in court. It may be rational to assume that Site Plan Review as attached to a by-right process, would be considered reasonable review since the use of the land for the intended purpose is still "as of right". It may also be reasonable to assume that using Site Plan Review in the context of a Special Permit would not be considered legal as the community would be assuming the right to deny the use or condition in a way that was legally binding. As mentioned above, these assumptions have yet to be tested in court.

Site Plan Review, as attached to by-right uses, should be viewed as essentially an administrative review and is therefore best used when the community has a high comfort level with the uses that are allowed by-right. The integration of Site Plan Review into an existing bylaw or ordinance should therefore be viewed primarily as an opportunity for local boards to receive more information about incoming development. It should not be viewed primarily as an opportunity for local boards to regulate or deny development. Communities that use Site Plan Review with by-right uses have the advantage of providing guidance to developers that other communities without Site Plan Review do not. Opportunities that could be missed without a process like Site Plan Review may include:

  • Access and Egress. Local boards will often have a better understanding of traffic flow in a particular area and can advise developers how to accommodate these conditions through Site Plan Review.
  • Existing Drainage Patterns. Even with the best topographic surveys, developers may not understand some of the intricacies of local drainage patterns as well as municipal engineers, particularly in older developed areas with outdated infrastructure. These problems can be mitigated through the Site Plan Review process.
  • Buffer Zones. Local officials will often have a better idea of the nature of abutting uses and can more appropriately advise developers regarding the size and design of any required buffers.
  • Adjacent Site Features. One of the most important opportunities in Site Plan Review is for local Boards to point out what they like in properties close to where the development is proposed. If detailed design standards are not in place, municipal officials can use the Site Plan Review process to point out lighting fixtures, building materials, landscape features, and other site elements that are preferable to the area. In this manner, a more consistent streetscape can begin to emerge over time using the coordinated review.

Special Permits

The Basics of Special Permits in Massachusetts

The Special Permit process is specified in the Massachusetts Zoning Act, M.G.L Chapter 40A, Section 9. The statute specifically allows for the following uses under a Special Permit process:

  1. Increases in the permissible density of population or intensity of a particular use.
  2. Authorization of Transfer of Development Rights (TDR) of land within or between zoning districts.
  3. Review of cluster developments, pursuant to the Subdivision Control Law (M.G.L. Ch. 41, §81K to 81GG).

Special Permits may be administered by the Zoning Board of Appeals, the Planning Board, the City Council, or the Board of Selectmen. Communities should carefully consider the appropriate authority for different situations and avoid duplicative and unnecessary permit submittals. For example, if the activity will likely require a subdivision, then the logical choice for a permitting authority would be the Planning Board. Approval of a Special Permit requires a supermajority vote of the administering Board. Similar to Site Plan Review, a Special Permit Granting Authority may adopt Rules and Regulations associated with the Special Permit process. Unlike the Site Plan Review regulations, however, these regulations are generally reserved for procedural items and can be very effective in specifying the contents of plans, the approval procedures and any other administrative items such as surety bonds associated with proposed developments.

Special Permit provisions should include the following basic elements within the bylaw or ordinance:

  • Process (What is the submittal, public hearing, and approval process?)
  • Plan Requirements (What information is needed to make a decision?)
  • Standards (What unique design or use standards apply to the use or area?)
  • Decision (What will the procedure be for issuing and recording a decision?)

Special Permit provisions must include the following elements within the bylaw or ordinance:

  • Findings or Criteria for Approval (How will the permitting authority determine if the use is appropriate?)
  • Lapse provision specifying the period of time when a special permit will lapse. This period can not be more than two years and does not include the period of time to pursue or await the determination of an appeal of the special permit decision.
  • Applicability (What type of development needs a Special Permit?)
  • Authority (Who is the permit granting authority?)

According to Massachusetts statute, applications for a Special Permit may be denied, approved, or approved with conditions. Appeals of any decision are heard "in a court of competent jurisdiction". Because these decisions are specifically enabled by statute, they are considered very enforceable and often survive appeal in a court of law.

Important Considerations for Local Practitioners

Special Permit review is available to assist town government in making decisions regarding land uses that can impact neighbors, neighborhoods, community character, the environment, and the local economy. Historically, Special Permits are often associated with a more restrictive review process for areas such as flood plains and aquifer protection zones. Specific uses can also be singled out for higher levels of review such as industrial/commercial uses of a certain scale. Although the types of restrictions in these instances may be entirely appropriate to protect adjacent uses or natural resources, the development community will often steer away from these areas unless the market provides enough of an incentive to enter into a more arduous permitting process.

More recently, the Special Permit process is being used in a more development-friendly manner to help smart growth/smart energy implementation by enabling innovative approaches, allowing flexibility, encouraging partnership between the community and the developer, providing incentives, and requiring specific design standards. Special Permits can also be used to allow for the redevelopment of pre-existing non-conforming uses in a way that encourages infill and adds a favorable or needed use to an area. When considering the use of a Special Permit in the context of smart growth/smart energy implementation, three critical factors emerge from the Special Permit process: Administration, Discretion, and Enforcement.


The Special Permit process requires a formal hearing (outlined in M.G.L. Chapter 40A: Zoning) that includes specific procedures which must be followed in order for a community to maintain control over an application. Requirements for notification, postings, and recordings are all an integral part of the Special Permit process. In addition to these procedural requirements, communities will often require sophisticated site plan submittals with thorough engineering or legal components. It is therefore critical that a community prepare to administer all of the procedural and substantive aspects of this process before adopting a Special Permit provision in the local bylaw or ordinance.


Perhaps the most attractive aspect of the Special Permit is the ability it provides the permitting authority to exercise discretion in regard to a proposed development. Many developers see this as a disadvantage because of the uncertainty associated with many existing bylaws or ordinances and because their application may ultimately be denied. However, recent trends have demonstrated that a clearly crafted Special Permit bylaw can not only create a transparent set of standards but can also empower local authorities to significantly increase the amount of development beyond what the base zoning would allow. Provisions for shared or off-site parking and density bonuses are two increasingly common incentives implemented through a Special Permit process. As an example, communities have successfully used density bonuses as incentives for the protection of important open space and for the provision of affordable housing.


The final consideration for communities is in the realm of enforcement. Because the Special Permit process comes directly from the statutes, communities often feel more comfortable with their ability to enforce denials or conditions in the case of appeals. The history of case law indeed suggests that Special Permit decisions are more likely to survive appeal than decisions enforced outside of the statutes, such as those associated with a formal Site Plan Review.

Overlay Districts

The Basics of Overlay Districts in Massachusetts

An Overlay District is a type of land use zoning district that "lies" on top of the existing zoning and potentially covers many underlying districts or portions thereof. The use of Overlay Districts provides communities with an opportunity to meet the unique needs of geographic areas that may either require higher levels of protection or that may not be reaching their fullest development potential. Overlay Districts provide one of the most flexible means to alter zoning as they can impose either greater restrictions or more flexible provisions depending on the goals for the district. Examples of typical overlays that are more restrictive include those for sensitive resources such as flood plains or aquifer protection districts. Examples of typical overlays that are more flexible include those for village centers, receiving zones in a Transfer of Development Right (TDR) program, or other areas designated for higher levels of density and economic development.

Overlay Districts are specified by statute and can be established with either optional or mandatory requirements upon the underlying land. Generally, once an Overlay District is established, the requirements of that district supersede provisions in the underlying zoning where standards and procedures are different. Overlay Districts with optional requirements provide incentives or disincentives to landowners and developers to encourage or discourage certain types of development. Examples of this type of zoning overlay include Village Center Overlays that could encourage certain design standards for the purposes of allowing innovative techniques such as shared parking or more coordinated placement of multiple primary structures.

Overlay Districts with mandatory requirements may supplement or preempt the underlying zoning provisions. Typical examples of these overlays are resource-based restrictions such as aquifer protection or flood plain overlay districts. Overlay districts that are mandatory generally prove to be more effective as optional provisions are generally avoided unless aggressive incentives are associated with these provisions. Also, the optional overlay approach creates a situation in which some developers may choose to follow the incentives and some may not. For example, in an optional overlay model, a Village Center Overlay District may provide some density bonuses for reduced setbacks and enhanced architectural design. If some developers take advantage of this opportunity and others do not, the resulting street line could have buildings sitting along incongruent setbacks, built at highly varied densities and appearing completely unrelated from an architectural perspective.

Important Considerations for Local Practitioners

One characteristic of Overlay Districts that is very appealing is the geographic focus of this technique. In many communities, the unique needs of a specific area emerge over time, perhaps through the comprehensive planning process, and it may be challenging to alter the zoning in that area for two reasons. First, the area of interest may cover portions of several existing zoning districts and it may be politically and administratively difficult to develop a new district for that area. Second, changing provisions to the underlying zoning may affect other areas of the community that do not share the same needs. The Overlay approach, therefore, represents one of the most effective ways to tailor zoning regulations to a specific neighborhood or environmental resource.

Another appealing element of an Overlay District involves an issue of perception. Quite often, Town Meeting voters, local officials, or City Council members will feel threatened by the notion of redrawing the base zoning districts or radically changing the regulations that apply to existing districts. Overlay Districts are often perceived as less threatening since they do not alter the basic fabric of a bylaw or ordinance that may have been in use for decades. Conversely, local officials should be careful not to over-use this approach as it can make a bylaw or ordinance extremely confusing. Multiple overlays can make it difficult for applicants and enforcement agents to determine if overlay or underlying provisions apply. In worst case scenarios, more than one overlay lies over a property that already has a base zoning district. This scenario can create a tangle of regulations that will serve as a deterrent to any significant redevelopment opportunities and to quick and transparent permitting.

The most common form of Overlay District in Massachusetts is often called a "Mixed-Use District" or "Village Center" overlay. Generally, the intent of these overlay districts is to retrofit existing municipal centers with clearer allowances for mixed use, more creative dimensional requirements, and other supporting mechanisms such as shared parking or design guidelines. Perhaps one of the most important considerations for these situations is whether to use an Overlay District or to simply re-zone the focus area to achieve a pattern of Traditional Neighborhood Development (TND). The issues that must be considered to best answer this question are numerous and will vary from one community to the next. Some of the more important considerations include:

  • How many underlying districts are within the target area? From a practical standpoint, if a study area has a significant number of underlying districts, using an overlay may provide a very clean way to impose a uniform set of requirements and incentives over a wide variety of existing provisions.
  • Are there already existing overlay districts present? Placing overlay districts on top of overlay districts should be avoided as this situation can obviously create confusion for both developers and local officials.
  • Do the goals of the district suggest that 40R is an option? If affordable housing, specific design standards, and higher density are a major component of local planning, then municipalities may want to consider a Smart Growth Overlay District through Chapter 40R.
  • What is the political climate of the community relative to zoning? If there is consensus within the community that the existing bylaw or ordinance is in need of major revision, local practitioners may want to consider re-districting to achieve more compact, village scale development. Conversely, if there is tremendous resistance to significant changes to the base zoning in a community, an overlay may be much more palatable.
  • How would changing existing provisions negatively affect other areas of the community? Perhaps the easiest approach to this type of zoning change is to simply re-work the standards and regulations in an existing district. Many communities do have individual districts, such as "Central Business Districts" that cover an existing village center. It will be important to remember, however, that this district may also exist elsewhere in the community in an area with different planning goals. Changing the provisions could therefore have unintended consequences elsewhere.
  • Are there existing permitting processes that would conflict with an overlay? A close look at existing zoning provisions may reveal some Special Permit requirements that deserve attention. For example, an existing town center could have many "non-conformities" that require Special Permits from the ZBA for specific activities. Establishing an overlay in this context could create onerous or duplicative permitting processes that work to limit interest in redevelopment. In these cases, re-districting or revising underlying zoning may be a more effective way to achieve TND planning goals.

As with any zoning bylaw or ordinance provision, the clarity of the overlay language will play a critical role in its success or failure. With Overlay Districts, clarity is generally determined by defining what is required of applicants and how the overlay relates to the underlying zoning in a very focused "purpose and intent" section. Overlay Districts that present a wealth of optional material will generally be less successful than those that require clear standards. Unless significant flexibility and/or incentives accompany optional requirements, applicants are more likely to choose the clearest path to approval. With regard to the underlying zoning, practitioners are encouraged to draw clear lines between what the overlay controls and what provisions of the underlying zoning remain in effect. Asking applicants to cross-reference multiple subsections of an overlay against provisions associated with underlying districts invites confusion into the permitting process and can be counter-productive for smart growth implementation.


Choosing an appropriate zoning approach for individual smart growth or smart energy techniques can be challenging, as communities will need to balance the desire for control over certain site plan elements with the desire to attract better development through flexibility or incentives. Integral to understanding which techniques will best suit a community or a particular district is a well developed Comprehensive Plan. For example, the plan will specifically address the desired uses for each district and those that have a high comfort level within the community. These uses should receive by-right privileges with a possible administrative Site Plan Review attached to the permitting process. Where the Comprehensive Plan identifies sensitive environmental areas, potentially harmful uses or areas that may require high levels of discretionary authority (such as mill complexes), a Special Permit process that includes Site Plan Review may be the best approach. Finally where the boundaries of a sensitive area include multiple districts (such as a flood plain) or a revitalization effort may be targeted to a unique setting (e.g. existing village center or mill complex), an overlay district approach may be the most efficient way to "retrofit" the zoning in that setting. Framing a zoning approach for any of these situations will become much more transparent in the wake of a comprehensive planning exercise that clearly spells out the goals for growth, environmental protection and economic development throughout the community.