Except as herein after provided, this bylaw shall not apply to structures or uses lawfully in existence or lawfully begun, or to a building permit or special permit issued before the first publication of notice of the public hearing on this bylaw or any amendments thereto, but shall apply to any change or substantial extension of such use, to a building permit or special permit issued after the first notice of said public hearing, to any reconstruction, extension or structural change of such structure and to any alteration of a structure begun after the first notice of said public hearing to provide for its use in a substantially different purpose or for the same purpose in a substantially different manner or to a substantially greater extent except where alteration, reconstruction, extension or a structural change to a one-family or two-family residential structure does not increase the nonconforming nature of said structure, as set forth below.
8.1.1 
Commencement of Construction or Operation. Construction or operations under a building permit or special permit shall conform to any subsequent amendments to this bylaw, unless the use or construction is commenced within a period of not more than six months after the issuance of the permit and in any case involving construction, unless such construction is continued through to completion as continuously and expeditiously as is reasonable.
8.2.1 
Change or Substantial Extension. The SPGA may grant a special permit to change or substantially extend a nonconforming use only if it determines that such change or extension shall not be substantially more detrimental than the existing nonconforming use to the neighborhood.
8.2.2 
Substitution. The SPGA may grant a special permit to substitute one nonconforming use for another nonconforming use only if it determines that the new use shall be less detrimental than the existing use to the neighborhood.
The SPGA may grant a special permit to reconstruct, extend, alter or structurally change a nonconforming structure other than a one-family or two-family structure (which are governed by § 8.4, below), or to alter said structure to provide for a substantially different purpose or for the same purpose in a substantially different manner or to a substantially greater extent, in accordance with this section only if it determines that such reconstruction, extension, alteration, or change shall not be substantially more detrimental than the existing nonconforming structure to the neighborhood. No part of a structure that does not conform to a minimum yard requirement shall be located closer to a lot line than the closest point of the existing structure to such lot line. No part of a structure that does not conform to a height requirement shall be higher than the existing structure.
8.4.1 
No Increase in Nonconforming Nature. Nonconforming one-family and two-family dwellings may be reconstructed, extended, altered, or structurally changed, or a new accessory structure may be constructed, upon a determination by the Building Commissioner that the nonconforming nature of the structure is not increased. Such determination will be deemed to be as of right and the applicant entitled to the issuance of a building permit where each structure is reconstructed, extended, altered, or changed so as to (a) contain the improvements within the site coverage and height of an existing structure; or (b) comply with the applicable yard and height requirements of § 135-4.0, except that the side yard may be reduced as noted below:
[Amended 3-30-2016 ATM by Art. 39]
If Actual Lot Frontage Is
Side Yard Must Be At Least
More than 75 feet but not more than 100 feet
12 feet
More than 50 feet but not more than 75 feet
10 feet
More than 0 feet but not more than 50 feet
7.5 feet
8.4.2 
Increase in Nonconforming Nature. In the event that the Building Commissioner determines the nonconforming nature of the structure is increased, the SPGA may grant a special permit to allow such construction, reconstruction, extension, alteration, or change where it determines that the proposed modification does not create a new nonconformity and will not be substantially more detrimental to the neighborhood than the existing nonconforming structure.
8.5.1 
Changes to Nonconforming Lots. A lot that does not currently comply with the dimensional requirements set forth in § 135-4.0 may be changed provided that such change reduces or does not increase the extent of the existing nonconformity and does not create a new nonconformity. Such change shall not cause the protected status of the lot to be forfeited and the lot shall be considered a nonconforming lot.
8.5.2 
Government Acquisition. If government acquisition of land causes a lot to be rendered nonconforming, or more nonconforming, it shall not cause the protected status of the lot to be forfeited and the lot shall be considered a nonconforming lot.
[Amended 4-9-2014 ATM by Art. 32]
Any nonconforming use or structure which has been abandoned, demolished without reconstruction, or not used for a period of two years, shall lose its protected status and be subject to all of the provisions of this bylaw; provided, however, that the SPGA may grant a special permit to authorize the reestablishment of a nonconforming use or structure where such reestablishment shall not result in substantial detriment to the neighborhood.
[Amended 3-25-2015 ATM by Art. 52; 3-23-2016 ATM by Art. 37]
8.7.1 
Existing Nonconforming Parking Spaces or Loading Bays. Any off-street parking spaces or loading bays in existence on the effective date of this bylaw or thereafter established, which serve a building or use, may not be reduced in number, or changed in location or design contrary to the requirements of § 5.1 so as to increase the degree of nonconformity with the requirements of § 5.1.
1. 
Change of Use. A use of an existing structure or lot which does not have sufficient parking or loading, including a use which has no off-street parking or loading, may be expanded or changed to a different type of use for which a different number of parking spaces or loading bays is required as set forth in § 5.1.4 only if the net increase in the number of required parking spaces or loading bays is provided in conformity with § 5.1.
2. 
Increase in Floor Area. If it is proposed to increase the net floor area of a building, whether by addition to the exterior of the building or by internal reconstruction, and the building does not have sufficient off-street parking or loading bays, full compliance with § 5.1 for the entire building shall be a condition of the issuance of a building permit for the construction of the increase of net floor area.
3. 
Parking Spaces or Loading Bays in Existence. Parking spaces or loading bays lawfully in existence which serve existing uses, are no longer required for those uses under § 5.1, and comply with the design standards of § 5.1.13, as to dimensions, loading bays, surfacing, and grade, may be transferred to a new, changed, or expanded use in an existing structure, even if they do not conform to the requirements of § 5.1.13 as to setbacks, snow storage, access for a parking lot, and landscaping.
4. 
Parking Spaces or Loading Bays in Existence. Existing parking spaces or loading bays that comply with the design standards of § 5.1.13, as to dimensions, loading bays, surfacing, and grade, that are no longer required for existing uses under § 5.1, may be transferred to a new, changed, or expanded use in an existing structure, even if they do not conform to the requirements of § 5.1.13 as to setbacks, snow storage, access for a parking lot, and landscaping.
5. 
Credit. An applicant seeking credit for existing parking spaces or loading bays shall first submit an off-street parking and loading plan, as provided in § 5.1.3, certified by a registered land surveyor or professional engineer. If the existing paved area is not marked off into parking spaces or loading bays, such spaces or bays, complying with § 5.1.13 shall be delineated on the plan. To qualify, an existing parking space or loading bay shall be entirely on the lot.
8.7.2 
Reconstruction or Replacement of a Building.
1. 
If a building, for which sufficient off-street parking or loading is not provided, is destroyed, damaged or demolished by the owner, the building may be reconstructed or replaced if otherwise permitted by this bylaw, without providing additional parking spaces or loading bays provided the new building has the same or less net floor area and the new uses require the same or fewer parking spaces or loading bays. If parking spaces or loading bays were provided before the destruction, damage, or demolition, at least the same number of spaces or bays shall be provided.
2. 
If the uses require a greater number of parking spaces or loading bays, or if more net floor area is to be constructed than previously existed, full compliance with § 5.1 for the entire building shall be a condition of the issuance of any building permit for the reconstruction or replacement of the building.