Mamaroneck City Zoning Code
ARTICLE VIII
Supplementary Regulations
§ 240-49 Construal of provisions.
The provisions of this chapter shall be subject to such exceptions, additions or modifications as herein provided by the following general supplementary regulations.
§ 240-50 Terraces and porches.
[Amended 4-17-1963; 7-17-1996 by L.L. No. 14-1996]
A paved terrace or wood deck, not more than 18 inches above average adjacent grade, as measured to the finished deck, top or stone surface, whether adjacent to a dwelling or not, shall not be considered in the determination of yard size or lot coverage; provided, however, that such terrace is unroofed and without walls, parapets or other forms of enclosures; but such terraces may have an open guardrail not over three feet high and shall not project into any yard to a point closer than five feet from any side or rear lot line. Any porch, either open or enclosed, shall be considered a part of the building in the determination of the size of the yard or the amount of lot coverage.
§ 240-51 Projecting architectural features.
A.
Cornices, eaves, chimneys, bay windows, windowsills, belt courses and other architectural features may project not more than two feet into any required yard. The sum of any bay window projections on any wall shall not exceed 1/4 the length of such wall, and no such projecting bay window shall have a total length of more than 10 feet nor be more than one story in height. Provided their total area does not exceed 40 square feet, steps and their platforms are permitted to project into any required side or rear yard a distance of not more than five feet and into a required front yard a distance of no more than eight feet.
[Amended 7-17-1996 by L.L. No. 14-1996; 10-15-2008 by L.L. No. 8-2008]
B.
Fire escapes. Open fire escapes may extend into any required yard not more than six feet; provided, however, that such fire escape shall not be closer than four feet at any point to any lot line.
§ 240-52 Walls and fences.
[Amended 2-7-1996 by L.L. No. 3-1996; 1-19-2005 by L.L. No. 1-2005; 4-2-2025 by L.L. No. 2-2025]
A.
The yard requirements of this chapter shall not be deemed to prohibit any necessary retaining wall nor to prohibit any fence or wall, provided that in any residence district such fence or wall shall not exceed four feet in height in any required front yard and/or five feet in height in any required side or rear yard, except for fences or walls surrounding a Tier 3 solar system (defined in Chapter 181) which can be as high as seven feet in height. For the purposes of this chapter, the height of any retaining wall shall be included in the computation of the height of a wall or fence placed on top of or above such retaining wall or at a distance of four feet or less horizontally from the retaining wall, in determining whether or not a wall or fence meets the heights restrictions of this provision.
B.
Gates, posts, capitals and pillars shall comply with the height requirements of this provision, except that ornamental or decorative features on top of posts, pillars, capitals and gates may exceed the height limitations of this provision by no more than 12 inches. However, no more than 10% of the total length of a fence or wall, including gates, posts, capitals and pillars, may have an ornamental or decorative feature which exceeds the height limitations set forth in Subsection A.
C.
Six-foot fences are permitted in business or commercial districts in the side and rear yards only.
E.
Fences which have a finished or textured side and an unfinished side and which are erected on or near a boundary line separating two or more lots or on or near the boundary line separating a lot from a street shall be erected so that the finished or textured sides face the neighboring lot or lots or the street, as the case may be. In addition, the supporting elements for such fences, such as beams, columns, pipes, posts, wires and the like, shall not be placed or located against or on the same side as the finished or textured side of such fences if more than 1/2 of the length or height of such supports is visible only from one side of the fence.
§ 240-53 Visibility at intersections.
At any street intersection in any residential district, no fence, wall or other structure or planting more than three feet in height shall be erected, placed or maintained within the triangular area formed by the intersecting street lines and a straight line joining said street lines at points which are 30 feet distant from the point of intersection, measured along said street line. The height of three feet shall be measured above the road surface at the nearest edge of the road. This subsection shall not apply to existing trees, provided that no branches are closer than six feet to the ground. This provision shall be in addition to the provisions of § 161-4 of this Code.
§ 240-54 Corner lots.
On a corner lot in any residence district, there shall be provided a yard on each street equal in depth to the required front yard on such streets. A rear yard shall be provided on each corner lot, and the owner shall elect which yard is the rear yard.
§ 240-55 Courtyards.
The least dimension of any inner court at the sill level of the lowest windows shall be equal to the height of the highest wall forming a part of such court. The depth of any outer court shall not exceed one-half (1/2) its width, and such width shall not be less than 15 feet.
§ 240-56 Height exceptions.
A.
The height limitations of this chapter shall not apply to spires, cupolas and domes of churches nor to chimneys, ventilators, skylights, water tanks, bulkheads or similar features and necessary mechanical or amateur electronic devices and appurtenances usually carried above the roof level. Such features, however, shall be erected only to such heights as are necessary to accomplish the purpose they are intended to serve, and the total area covered by such features shall not exceed 10% of the area of the roof on which they are located. Exceptions to the ten-percent area limitation may be provided for energy conservation devices; provided, however, that application for any such exception shall not be treated as a request for a variance under this chapter but shall be filed with the Town Board as an application for a special use permit pursuant to §§ 240-60 through 240-65 of this Code. The Town Board may refer any such application to other official bodies for comment and recommendation before acting thereupon. No structure having a height of more than 70 feet in an R-TA District, more than 87 feet in a B-MUB District, or more than 50 feet in any other district shall be erected unless approved by the Board of Appeals.
[Amended 3-21-1979; 5-25-2005 by L.L. No. 9-2005; 6-21-2006 by L.L. No. 13-2006]
B.
The provisions of this chapter shall not prevent the erection above the building height limit of a parapet wall or cornice, for ornament and without windows, extending above such height limit not more than five feet.
§ 240-57 Minimum house size.
[Amended 4-17-1963]
No dwelling unit erected or created by alteration subsequent to the adoption of this chapter shall have a first-floor area less than that required in the schedule of regulations. Such floor area shall include all floor area used for human occupancy within the exterior walls of the building, as defined in Chapter 106, Fire Prevention and Building Construction, of the Code of the Town of Mamaroneck, but shall not include open porches or breezeways, garages, basements or uninhabitable attic space. For the purpose of this section, the first-floor area of a split-level house shall be deemed to be the total area of the lowest habitable floor or floors. Where the second-story area, in square feet, used for human occupancy exceeds the minimum first-floor area as required by this section and the schedule of residence district regulations referred to in § 240-20 of this chapter, the minimum house size, in square feet, shall be the area of the second story used for human occupancy.
§ 240-58 Dwellings in house trailers and accessory buildings.
A.
House trailers, as defined in this chapter, shall be prohibited from all districts, except that one trailer may be parked or stored in an enclosed accessory garage or accessory building as set forth in § 240-21C(8), provided that no living quarters shall be maintained nor any business conducted in connection therewith while such trailer is stored.
[Amended 7-17-1996 by L.L. No. 14-1996]
B.
Any accessory building on the same lot with a main residence building shall not be used for residence purposes, except for domestic employees of the owners or of the tenants of the main building who are employed on the premises.
§ 240-59 Air-conditioning systems.
[Added 12-5-2001 by L.L. No. 8-2001; 11-3-2021 by L.L. No. 15-2021]
A. AREA CENTRAL AIR-CONDITIONING SYSTEM EXISTING CENTRAL AIR-CONDITIONING SYSTEM PAD REPLACEMENT SYSTEM
For the purposes of this section and for no other purpose, the following terms are defined as follows:
The square footage of the horizontal plane on which an air-conditioning system or its pad is situated.
A system that consists of one or more heat exchanges, blowers, filters, supply, exhaust and return-air systems and any apparatus installed in connection therewith.
Any air-conditioning system that existed on September 1, 2001.
Any artificial surface on which an air-conditioning system is situated.
Any central air-conditioning system that replaces either:
B.
An existing central air-conditioning system shall not be required to meet the current zoning requirements unless such system is moved from where it was located on September 1, 2001.
C.
Installation of new central air-conditioning systems, replacement systems and any existing central air-conditioning system that is moved from the place where it was located on September 1, 2001 shall require a building permit and a letter of completion from the Building Inspector or the Director of Code Enforcement and Land Use.
§ 240-59.1 Maximum size of one- or two-family homes.
[Added 1-8-2003 by L.L. No. 1-2003]
A. APPLICANT AVERAGE COMPARISON PARCEL(1) (2) (3) SEASONAL PORCH SUBJECT PROPERTY TOTAL SQUARE FOOTAGE
Definitions. As used in this section, the following terms shall have the meanings indicated:
The owner of the subject property. The applicant may authorize another person to act in the applicant's behalf.
The total square footage of all of the buildings on all of the comparison parcels divided by the number of comparison parcels.
Any lot which:
Has a lot line that lies within 300 feet of any of the lot lines of the subject property and abuts one of the streets that the subject property abuts; or
Has a lot line which, in whole or in part, is the same as one of the lot lines of the subject property; or
Touches the subject property at any point.
Any structure that:
The lot for which a building permit is sought.
The aggregate floor area of all of the buildings on a lot, exclusive of the aggregate floor area of any basements, regardless of their use.
B.
Maximum permitted total square footage and floor area ratio.
(1)
The maximum permitted total square footage of all of the buildings on a lot shall be the greater of:
(2)
The maximum floor area ratio for a lot shall be determined by the following chart:
1 | 2 | 3 | 4 |
|---|---|---|---|
For a Lot Whose Size Appears in a Row (square feet) | The Maximum Floor Area Ratio Shall Be | The Maximum Total Square Footage for a Lot whose Size is Shown in Column 2 of this (square feet) | |
1 | 1,000 | .55000 | 550.00 |
2 | 2,000 | .55000 | 1100.00 |
3 | 3,000 | .55000 | 1650.00 |
4 | 4,000 | .55000 | 2200.00 |
5 | 5,000 | .55000 | 2750.00 |
6 | 6,000 | .55000 | 330.000 |
7 | 7,000 | .52000 | 3640.00 |
8 | 8,000 | .49000 | 3920.00 |
9 | 9,000 | .46000 | 4140.00 |
10 | 10,000 | .43000 | 4340.00 |
11 | 11,000 | .41000 | 4510.00 |
12 | 12,000 | .39000 | 4680.00 |
13 | 13,000 | .36900 | 4797.00 |
14 | 14,000 | .35000 | 4900.00 |
15 | 15,000 | .33400 | 5110.00 |
16 | 16,000 | .32000 | 5120.00 |
17 | 17,000 | .31000 | 5270.00 |
18 | 18,000 | .30000 | 5400.00 |
19 | 19,000 | .29000 | 5510.00 |
20 | 20,000 | .28100 | 5620.00 |
21 | 21,000 | .27250 | 5722.50 |
22 | 22,000 | .26500 | 5830.00 |
23 | 23,000 | .25820 | 5938.60 |
24 | 24,000 | .25200 | 6048.00 |
25 | 25,000 | .24600 | 6150.00 |
26 | 26,000 | .24070 | 6279.00 |
27 | 27,000 | .23200 | 6264.00 |
28 | 28,000 | .22760 | 6372.80 |
29 | 29,000 | .22350 | 6481.50 |
30 | 30,000 | .21960 | 6588.00 |
31 | 31,000 | .21600 | 6696.00 |
32 | 32,000 | .21250 | 6800.00 |
33 | 33,000 | .21000 | 6930.00 |
34 | 34,000 | .20750 | 7055.00 |
35 | 35,000 | .20500 | 7175.00 |
36 | 36,000 | .20375 | 7335.00 |
37 | 37,000 | .20250 | 7492.50 |
38 | 38,000 | .20125 | 7647.50 |
39 | 39,000 | .20000 | 7800.00 |
40 | 40,000 | .19875 | 7950.00 |
41 | 41,000 | .19815 | 8124.15 |
42 | 42,000 | .19755 | 8297.10 |
43 | 43,000 | .19695 | 8968.85 |
44 | 44,000 | .19635 | 8639.40 |
45 | 45,000 | .19575 | 8808.75 |
46 | 46,000 | .19545 | 8990.70 |
47 | 47,000 | .19485 | 9352.80 |
48 | 48,000 | .19485 | 9352.80 |
49 | 49,000 | .19455 | 9532.95 |
50 | 50,000 | .19425 | 9712.50 |
(3)
The maximum permitted total square footage for a lot whose size lies between the lot sizes shown in Column 2 of any two adjacent rows on the chart contained in Subsection B(2) of this section shall be equal to:
(a)
The maximum total square footage set forth in Column 4 of that chart for the lot referred to in Column 2 of the lower numbered row; plus
(b)
Ten square feet for each 100 square feet (or part thereof) by which the lot exceeds the size of the lot referred to in Column 2 of the lower numbered row.
Example: The maximum permitted total square footage for a lot that is 20,725 square feet in size is determined as follows: The size of the lot lies between the sizes of lots referred to in rows 20 and 21 on the chart. The maximum total square footage for a lot that is 20,000 square feet in size is 5,620.00 square feet. The lot in this example exceeds the square footage of the lot in Row 20 by 725.00 square feet. Accordingly, the lot is entitled to additional square footage of 10 square feet x 8 = 80.00 square feet. Hence, the maximum permitted total square footage for a lot equal to 20,725 square feet in size is 5,620.00 + 80.00 = 5,700.00. |
(4)
The maximum permitted total square footage for any lot whose size is greater than 50,000 square feet shall be 9,712.50 square feet plus 10 square feet for each 100 square feet (or part thereof) by which the size of such lot exceeds 50,000 square feet. Under no circumstances, however, shall the maximum permitted total square footage for any lot exceed 15,000 square feet.
C.
The average.
(1)
If an applicant wishes to obtain a building permit which will result in the subject property having buildings whose aggregate total square footage exceeds the maximum permitted total square footage allowed for the subject property, the applicant can compute the average.
(2)
To determine the average, the applicant shall identify all of the comparison parcels by measuring the comparison distance from each of the lot lines of the subject property using the scale on the tax assessment map of the Town; compute the total square footage of all of the buildings on each of the Comparison Parcels by using the records of the Town's Building Department (If the records of the Town's Building Department do not contain sufficient information to determine the total square footage of all of the buildings on any comparison parcel, the applicant shall use the records of the Town's Assessor in order to make that determination); add the total square footage of all the buildings on all of the comparison parcels and divide that sum by the number of comparison parcels.
(3)
The applicant's computation of the average shall be given to the Town's Building Department. It shall be in writing and shall consist of a list of all of the comparison parcels identified by their street addresses and their tax block and lot designations on the Town's tax assessment map; the number of buildings on each comparison parcel; the total square footage of all of the buildings on each comparison parcel, the sum of the total square footage of all of the buildings on all of the comparison parcels; and the average. The applicant's architect or engineer shall certify the accuracy of the computation of the average. If there is no architect or engineer, the accuracy of the computation of the average shall be verified under oath by the applicant.
(4)
If the average is a figure that exceeds what the maximum permitted total square footage for all of the buildings on the Subject Property would be when applying Subsection B of this section, the Applicant shall be entitled to a building permit for construction which, when completed, will result in the total square footage of all of the buildings on the subject property being greater than what Subsection B of this section would allow but not greater than the average.
(5)
Nothing in this section shall relieve the applicant from satisfying all of the other requirements of this chapter and all of the requirements of every other law that must be satisfied before the Town's Building Department may issue a building permit.
D.
Applicability of this section.
(1)
This section shall apply only to a lot whose principal use is a one- or a two-family dwelling.
(2)
Exceptions.
(a)
A lot shall not be in violation of this section if the total square footage of all of the buildings on that lot will be greater than the maximum permitted total square footage allowed for that lot because of construction done or to be done pursuant to a building permit issued prior to the effective date of this section.
(b)
Assuming that there is compliance with all other requirements for the issuance of a building permit, a building permit shall be issued during the first 90 days after this section goes into effect for construction based upon building plans that shall have been filed with the Building Department before the effective date of this section even though no building permit shall have been issued before the effective date of this section and, upon completion of such construction, the total square footage of all of the buildings on that lot will be greater than the maximum permitted total square footage allowed for that lot. Starting on the 91st day after the effective date of this section, building plans filed with the Building Department prior to the effective date of this section shall no longer be exempt from the application of this section.
(3)
This section shall not apply to any lot for which:
(a)
An application for a variance shall have been filed prior to the effective date of this section; provided that such application either shall have appeared on the agenda of a meeting of the Board of Appeals held prior to the effective date of this section or is scheduled to appear on the agenda for the first meeting of the Board of Appeals after the effective date of this section; or
(b)
An application for an approval and/or a permit from the Planning Board shall have been filed prior to the effective date of this section; provided such application either shall have appeared on the agenda of a meeting of the Planning Board held prior to the effective date of this section or is scheduled to appear on the agenda for the first meeting of the Planning Board after the effective date of this section.
(4)
This section shall apply to any lot for which an interpretation of the Zoning Ordinance is being requested from the Board of Appeals.
(5)
An attic which exists on the effective date of this section and is not legally permitted to be used as habitable space (as that term is defined in the New York State Building Code in effect on January 1, 2003) can be converted to habitable space even though, upon completion of the conversion, the maximum permitted total square footage for all of the buildings on the subject property will exceed the maximum permitted total square footage allowed for that lot so long as after the conversion, the exterior walls of the building in which such attic is located remain in the same position and the sum of the horizontal length of all of the alterations in the roof line on a side of the building is no longer than 1/4 of the horizontal length of the wall beneath such roof on that side of the building.
(6)
A seasonal porch may be permanently enclosed even though upon completion of that work, the maximum total square footage for all of the buildings on the subject property will exceed the maximum permitted total square footage allowed for that lot so long as neither the exterior of the seasonal porch nor the exterior walls of the dwelling to which the seasonal porch is attached are relocated closer to the lot lines of the subject property after the permanent enclosure is completed.