Do It Yourself Repairs
New York City Specifications for Residents Installing their Own Sidewalk
1. DESCRIPTION: Sidewalks shall have a minimum width of five (5) feet. They shall be four (4) inches thick. (It is required that they be seven (7) inches thick across driveways.) Sidewalks shall slope toward the street one quarter (1/4) inch per foot (thus the closest edge to the street shall be one and a quarter (1 1/4) inches lower than the edge adjacent to the property line.) A foundation of six (6) inches of No. 3 stone or gravel be placed under the sidewalk. Expansion joints shall be installed as explained below.
2. SUBGRADE: All unsatisfactory material shall be removed and replaced with suitable material. Organics such as grass and other plant material must be removed. The entire sub base must be compacted until firm. The sub grade should be wet down thoroughly and should be damp at the time of pouring.
FOUNDATION: It is required that six (6) inches of No. 3 (1/2”) stone or gravel be placed under the sidewalk. It must be sufficiently compacted.
3. FORMS: Forms shall be made of metal or wood and extended not less than the full depth of the concrete. They shall be of substantial material so as to resist distortion when fastened together and secured. The tops are to be set to the designated sidewalk surface and left in place until the concrete has hardened.
4. REINFORCEMENT: When necessary, welded wire fabric (size: #8/8 @ 6”x6”) shall be installed 2” below the sidewalk. It should be laid in sheets which are straight and true to form and shall be held securely in position so that it does not move during the pour.
5. CONCRETE: Concrete shall consist of Type llA Portland Cement, size no.57 stone, and Type 1A Natural sand. It shall achieve a compressive strength of 3,200 PSI 28 days after the pour. For weather ability, it is to be air entrained, having an air content of 6.5% give or take 1.5%.
6. FINISHING: The top surfaces of the sidewalk shall be finished to a smooth surface by the use of screeds and wooden floats. Each rectangular slab shall have all edges neatly rounded, and bounded by a troweled border of one (1”) width. The concrete must be covered with a clear curing compound prior to it’s hardening and immediately after the water sheen has disappeared from it’s surface. Pigmented concrete should have curing compound applied that is color matched.
7. EXPANSION JOINTS: Expansion joints must be placed a minimum of every 20’ and should coincide with those of the curb. They shall be ¼” thick and filled with preformed joint filler positioned 1” below the sidewalk surface. The top 1” shall be sealed with Type 2 – sealer in accordance with the manufacturer’s instructions. Expansion joints should also be installed at all joints between the sidewalk slabs and curb, street hardware, wood pole slabs, street light and traffic pole foundations, bollard foundations, fire hydrant foundation slabs, buildings, bridges, etc. Around hydrants, and wood poles, sidewalk slabs shall be constructed as independent slabs, separated by expansion joints.
8. BACKFILLING: Backfilling shall follow the removal of the forms as soon as is practical. It is to consist of clean earth, satisfactorily compacted.