(1) 
Lawful structures and uses - Except as hereinafter provided, Article 10 shall not apply to structures or uses lawfully in existence or lawfully begun, or any structure:
a. 
For which a building permit has been issued prior to date of the first notice of a public hearing as required by MGL c. 40A, § 5 on an amendment to this bylaw, provided that construction commences within six months after the issuance of the permit and is thereafter continued through to completion as continuously and expeditiously as is reasonable, provided further, however, that if such building permit is renewed, such six-month period shall be extended for the renewal periods, but not more than 12 additional months, and provided further that no design changes occurring after the initial issuance of the building permit shall increase the intensity of the development of the building to which the building permit relate; or
b. 
For which a special permit has been issued prior to the date of the first notice of a public hearing as required by MGL c. 40A, § 5 on an amendment to this bylaw provided that the special permit has been exercised within a period of 12 months.
(2) 
Enforcement actions - Noncomplying structures 10 years or older. In accordance with MGL c. 40A, § 7, a structure, which has not been in compliance with this chapter, or with the conditions set forth in any special permit or variance affecting the structure, for a period of 10 years or more from the commencement of the violation may not be the subject of any enforcement action by the Town to compel the removal, alteration or relocation of such structure. Structures which qualify under MGL c. 40A, § 7, are considered to be nonconforming structures and are entitled to treatment as such as provided in this section.
(1) 
Preexisting nonconformities - Preexisting, nonconforming structures or uses may be extended, altered or changed only by special permit from the Zoning Board of Appeals. Any such change, extension, or alteration shall not be substantially more detrimental to the neighborhood than the existing nonconforming use or structure.
(2) 
Structures in existence as of January 1, 1970 - Any residential structure in existence as of January 1, 1970, not protected by the sections of Article 10, will be deemed to be conforming to the dimensional requirements of these bylaws, but any alteration, reconstruction, extension or structural change must conform to the current bylaw dimensional requirements.
(3) 
Review standards - Recognizing the need to provide some guidelines for determining actions that may be substantially more detrimental to the neighborhood, and recognizing there are basic and consistent principles of zoning which are broadly accepted, the following standards shall apply to the granting of a special permit or in making a finding that a structure or use is not substantially ore detrimental:
a. 
The factors enumerated in § 240-12.1E.;
b. 
The change, alteration, extension, or reconstruction of the structure or the change, alteration, or extension of the use may be allowed as maintaining or lessening any nonconformity without having to meet existing dimensional requirements; however, the extension of a structure may be considered substantially more detrimental after the Board of Appeals considers whether extension or alteration extends or creates a new dimensional nonconformity, impairs views or vistas, or does not reasonably conform to the average dimensions found in the neighborhood; and
c. 
Where the proposed use is regulated by other sections of this bylaw, the applicable standards of those sections shall also be considered in determining whether the proposal is substantially more detrimental.
Exempted from the requirement for a special permit are the following:
(1) 
Alteration, reconstruction, extension or structural change (collectively "alteration") to a nonconforming single- or two-family residential structure shall not be considered an increase in the nonconforming nature of the structure and shall be permitted by right under the following circumstances:
a. 
Normal repairs or replacement of parts of any nonconforming structure, provided that such repair or replacement does not constitute an extension of a nonconforming use of such structure.
b. 
Alteration to a conforming structure where the alteration will also comply with all applicable sections of the Zoning Bylaws in effect at the time of application, if the existing structure is located on a lot which is nonconforming as the result of a zoning change.
c. 
Alteration within the existing footprint of a nonconforming structure to comply with requirements of the Massachusetts Building Code.
d. 
Alteration to a nonconforming structure where the alteration will comply with all applicable sections of the Zoning Bylaw in effect at the time of application and will not increase the habitable space.
e. 
Alteration to a nonconforming structure on a lot of at least 20,000 square feet, where the alteration will comply with all applicable sections of the zoning bylaw in effect at the time of application, including, but not limited to setback, yard, building coverage and height requirements.
(2) 
Height increase - In cases where the applicant seeks to increase the height of any structure that encroaches on a required setback, where any increase in height will occur within such encroachment, there shall be no alteration as of right under this section.
(3) 
Interior alteration - The interior alteration of any otherwise conforming structure which does not change the nature of, nor increase the intensity of, a nonconforming use, and interior alterations of preexisting nonconforming structures for a use or uses which are otherwise allowed by zoning.
(4) 
Damage or destruction - Reconstruction of a legally nonconforming structure damaged or destroyed by fire or other accidental or natural cause, other than flood damage sustained to structures within Zones A and V Floodplains shown on the Flood Insurance Rate Maps of Falmouth, if the reconstruction is substantially the form it had at the time of damage or destruction, or in any form if within applicable setback requirements and not larger than previously, and if reconstruction is started within 24 months and completed within 36 months of the damage or destruction.
(5) 
Commercial accommodation - Reconstruction of any permitted commercial accommodation structure or unit(s), if for the purpose of rehabilitation, upgrade, and if the commercial accommodation was licensed and operational for the three years prior to the rehabilitation upgrade. The reconstruction will not allow rebuilding at a greater density, greater height or at a different location than previously existed.
(6) 
Accessory uses and structures - Not exempted under this subsection are accessory uses and structures.
(1) 
One dwelling per lot - Not more than one dwelling shall be erected on a single lot except for multifamily use as allowed for within designated zoning districts.
(2) 
Two or more dwellings on a single lot - Anything to the contrary in the Zoning Bylaw notwithstanding, the residential use of two or more dwellings on a single lot shall be deemed a preexisting nonconforming use if commenced prior to May 19, 1959. The use may only be altered, extended, or modified by special permit pursuant to § 240-10.3A, provided the Zoning Board of Appeals finds through a preponderance of credible evidence that this use commenced prior to May 19, 1959, and has not been abandoned or not used for a period of two years or more. In approving any alteration, extension, or modification the Zoning Board of Appeals shall require that the proposed number of dwelling units shall be limited to the same as in existence on May 19, 1959.
(3) 
Two or more structures on a lot - An existing, nonconforming use of two or more structures on a single lot, as of 1 January 1981, not previously used for year-round habitation, may not be altered, reconstructed, extended or changed structurally, except by special permit from the Zoning Board of Appeals. Year-round habitation is deemed to be an extension of use.
(1) 
Nonconforming lots - Except as provided in § 240-10.3B(1)a., any nonconforming lot having at least 20 feet of frontage on a street shall be eligible to apply for a building permit if it conforms to the provisions of any of the following §§ 240-10.3B(1)a. through (1)h:
a. 
Any increase in area or lot width requirements in the Zoning Bylaw shall not apply to a lot shown on a plan or described in a deed recorded at the Registry of Deeds as of January 1, 1981 for single-family residential use which at the time of the Zoning Bylaw change was not held in common ownership with any adjoining land, not otherwise protected by MGL c. 40A, § 6, conformed to then-existing requirements and had at least 7,500 square feet of area and 50 feet of frontage.
b. 
Any lot not held in common ownership with any adjoining land as of January 1, 1981, not protected by § 240-10.3B(1)a., shall be eligible to apply for a building permit if the lot has at least:
i. 
40,000 square feet or area in an AGAA/RAA District;
ii. 
20,000 square feet of area in an AGA/RA/PU District;
iii. 
10,000 square feet of area in an AGB/RB District; or
iv. 
7,500 square feet of area in an RC/GR District for single-family construction only.
c. 
Any lot not held in common ownership with adjoining land as of January 1, 1981, not protected by § 240-10.3B(1)a and (1)b, may apply to the Zoning Board of Appeals for a special permit to construct a single-family residence, if the lot has at least 7,200 square feet of area. If the petitioner's lot is located within a Water Resource Protection Overlay District, or within 300 feet of an estuary, hereinafter defined as a saltwater passage wherein the tide meets a flow of freshwater, or within 300 feet of a tidal marsh, tidal pone, tidal river as defined or, the Board of Appeals shall require information on the location of public and private wells within 300 feet of the site; a nutrient analysis of the receiving waters, taken from the site or from adjacent, undersized lots; a projection of the cumulative impact on water quality with the increased density; and a determination that the majority of the lots within the neighborhood are already developed in addition to the criteria specified in § 240-12.1E.
The Board of Appeals is encouraged to refer the petition to the Board of Health, the Board of Public Works and the Planning Board, in accordance with § 240-12.1G. These additional criteria and the responses of the Boards to which the petition is referred shall become a part of the decision. The Board of Appeals may impose certain restrictions designed to protect or improve the water quality of the area, such as, but not limited to requirement to keep the lot in its natural vegetation; maximum floor/area ratio; limitations in other ordinarily permitted uses which would tend to degrade the water quality; seasonal uses; or other health and environmental hazards.
d. 
Any lot held in common ownership with such adjoining lots, vacant as of January 1, 1981, may be treated as not held in common ownership if, as of January 1, 1981, a dwelling was in existence on all the other commonly held, contiguous lots, or if subsequent to January 1, 1981 the lot was no longer held in common ownership and a dwelling was permitted by special permit on each of such adjoining lots.
e. 
Any lot not held in common ownership with any land as of January 1, 1981, not protected by § 240-10.3B(1)a. or (1)b, may be eligible to apply for a building permit, without the benefit of the special permit required under § 240-10.3B(1)c. if the petitioner acquires another undersized vacant lot within the subdivision or immediate surrounding neighborhood and duly records a covenant at the Registry of Deeds running in favor of the Town. The covenant shall prohibit the erecting of any structure thereon.
In addition this provision applies if the petitioner acquires the development rights on another undersized vacant lot within the same subdivision and covenants a permanent development restriction against the development rights on the lot, such that the total of the area of the lot to be built upon plus the assignable area of the lot to be restricted equal the minimum size requirements of § 240-10.3B(1)c. More than one petitioner may participate in the acquisition of the undersized vacant lot or the entire lot, and as long as the sum of the restricted development area assignable to each petitioner does not exceed the sum of the area of the restricted lot.
f. 
Any lot held in common ownership with any adjoining land as of January 1, 1981, not protected by § 240-10.3B(1)d, may apply to the Planning Board for a special permit to construct a single-family residence if the lots are on roads which have been constructed as of April 1, 1982, in accordance with the Town Code Chapter 305, the subdivision rules and regulations, and if the lots are resubdivided so that the total area of the commonly held lots, when divided by the number of building permits to be requested, results in an area of land per single-family residence that equals at least 75% of the existing requirements for that zoning district. The additional criteria specified in § 240-10.3B(1)c. shall also be considered. In addition, the Planning Board may set aside one of the created lots as an open space lot as allowed under MGL c. 41, § 81U.
g. 
Any lot in an RB or AGB Zoning District, shown on a plan or described in a deed duly recorded at the Registry of Deeds before January 1, 1975, with an area of at least 20,000 square feet, shall be eligible for a building permit by right, as long as the lot width is 100 feet or greater, provided that the lot conforms to all other requirements of the Zoning Bylaws.
h. 
Any lot in a GR, RC, RB, RA, AGB or AGA Zoning District not held in common ownership with adjoining land as of January 1, 1994, shown on a plan filed at the Registry of Deeds before April 4, 1988, with an area of at least 45,000 square feet, lot width of at least 150 feet and frontage of at least 100 feet, shall be eligible for a building permit by right, provided that on any such lot otherwise ineligible for a building permit the number of bedrooms shall not exceed one bedroom per 13,500 square feet of lot area, unless additional bedrooms are allowed by special permit, in which case the Zoning Board of Appeals shall impose conditions to preserve and protect existing and potential sources of drinking water, including required use of a sewage disposal system with enhanced nitrogen removal.
Any nonconforming use which has been abandoned or not used for two years or more loses the protection of § 240-10.1A(1) and § 240-10.1A(2) and shall be required to conform to the current Zoning Bylaw.
(1) 
Residential use amnesty special permit - Within three years from the effective date of this Zoning Bylaw, an owner of a lot with one or more structures containing dwelling units which do not comply with the Zoning Bylaw may apply for a special permit to establish the units as lawfully nonconforming where the Zoning Board of Appeals determines by a preponderance of credible evidence that such noncompliance has been continuous since January 1, 1994, without any lapse for a period of two years or more; the provisions of § 240-12.1E shall also apply.
(2) 
Building Commissioner determination - The determination of the Building Commissioner or their designee stating what repairs or upgrades, if any, shall be required for occupancy pursuant to the special permit under § 240-10.4B shall accompany the special permit application and any repairs or upgrades determined as necessary shall be a condition of the special permit.
(3) 
Special permit conditions - Any special permit issued under this amnesty program shall also require that:
a. 
The subject property shall be served by the municipal sewer or an on-site waste disposal system that conforms to the State Sanitary Code as determined by the Health Department;
b. 
A deed restriction, covenant or other suitable instrument, acceptable to and enforceable by the Town, shall be recorded with the land records. This instrument shall restrict the leasing of any dwelling unit(s) allowed by this special permit, beyond the units allowed by right in the particular zoning district, to households with an income 80% or less of the Barnstable County median income as determined by the most recent federal census or other method acceptable to the Zoning Board of Appeals and further at a gross annual rent not to exceed 30% of the median income herein described. The property owner shall provide to the Zoning.
Board of Appeals documentation that certifies the income level and rent paid by the tenant on a yearly basis;
c. 
The number of units allowed by this special permit may not exceed those in existence for at least 20 years without a lapse of two years or more, and no subsequent modification of the special permit shall allow additional units or conversion to a nonresidential use; and
d. 
No special permit granted under this section may be used for commercial accommodations or summer rentals.