Above is a view into typical Brooklyn Brownstone rear yards, showing many decks and roof coverings constructed of combustible materials. Often, these structures have not been constructed legally.
Q: What are the legal requirements for the construction of a Deck in the Rear Yard of a Brownstone-type building?
A: When considering construction of a Deck, it is necessary to comply with the Department of Buildings requirements for Decks. Legalization of existing Decks can be problematic, because many have not been designed by an Architect or Engineer and no Permit was ever obtained. The NYC Department of Buildings is cracking-down on Deck requirements, as they can be hazardous from a structural or fire safety standpoint when constructed improperly. An Illegal Deck can also be a problem when selling a property or applying for a Certificate of Occupancy.
Below is a listing of the basic Deck requirements, distilled from NYC Department of Buildings Memorandums. New Decks would need to comply with the below in order to obtain Plan Approval. Existing Decks needing to be Legalized would have to be modified (as required) to comply with the below:
Definition of a Deck:
A Deck is a raised floor, supported by structural framing above the surrounding ground at the level of the first story of a house. A Deck must be constructed without a roof. An outdoor structure with a roof is not a Deck. It may be considered an additional room, in which case different zoning rules and NYC Building Code provisions will apply.
1 Only a NYS Registered Architect or Professional Engineer may design a Deck or porch. The Department of Buildings must approve the plans and issue a permit before any work begins.
2 Decks must be located at or below the floor level of the first story of a house.
3 A Deck may project up to eight feet (8’) beyond the face of the building into the required thirty foot (30’) rear yard.
4 There shall be no useable building or storage space underneath the Deck.
4 There must be at least three feet (3’) between the Deck and the SIDE or REAR LOT LINE, unless the Deck is constructed of non-combustible materials, such as steel, in which case it may be closer to the Property Lines.
5 All Decks must have a railing at least 42 inches high.
6 Spaces between railings and/or posts can be no greater than five inches.
7 Elevated Decks must be braced at the columns and where the beams and columns connect.
8 Decks must be able to withstand a minimum of 40 pounds per square foot plus the weight of the Deck. This is the same live load required as for the building itself. Thus, a Deck will usually require a structure as robust as that of the main house’s floor construction, rather than the flimsy, under-structured wood Decks that are commonly seen.
9 Decks must be properly anchored to a house or building. Nailing Decks instead of using proper anchors is a common mistake that often leads to accidents and can cause serious injuries.
10 A homeowner may construct a Deck, but is not allowed to perform plumbing or electrical work. If you use a contractor, the contractor must have a Home Improvement Contractor’s License.