Keeping You Safe, One Step at a Time



  1. All stairs must be sound, clean and level prior to installation.
  2. An application of leveling compound should be made over dished or worn stairs to provide a level-bearing surface for the safety stair treads.
  3. Smooth steps such as marble, terrazzo, tile, metal, etc. should be roughed up to insure good adhesion. Always vacuum steps clean to remove any loose particles.
  4. Other types of stair surfaces need to be thoroughly cleaned.
  5. Trowel a leveling compound against a straight-edge board held to the front of each step to provide a square edge.
  6. Begin at top of stairs and work downward. Leave until cured. (See manufacturer’s instructions).

CONCRETE and MASONRY STAIRS: NSS recommends using ¼” x 1¾” 410 Stainless Steel Phillips Flat Head Concrete Anchors. Drill pilot holes with a hammer drill fitted with a 3/16″ masonry bit, ½” deeper than the anchor itself.

STEEL STAIRS: NSS recommends using a hardened steel ¼” x 1″ Phillips Flat Head Self-tapping Floor Screw. Pilot hole is 13/64″. If you find the self- tapping screws are very hard to drive in, you may use a larger drill bit (7/32″) for your pilot holes, but be careful not to strip treads.

WOOD STAIRS: NSS recommends a ¼” x 1 ¼” Stainless Steel Wood Screw. Drill pilot holes with a 3/16″ drill, at least the depth of the anchor.


Shop vacuum, caulk gun, extension cord, drill, drill bits and screwdriver. For masonry installations: shop vacuum, caulk gun, extension cord, hammer drill, 3/16” masonry bits and screwdriver.


(A) Block off access to the stairway you will be working on to keep people out of the area. Put up signs and danger tape;

(B) Begin at bottom stair. Carefully lay stair tread upside down on the stair;

(C) Apply a ¼” bead of glue all the way around the perimeter of the bottom side of the tread, keeping approximately ¾” away from the outside edge of tread. Apply an additional ¼” bead in a wavy pattern on the remainder of the bottom side of the tread inside the perimeter bead, as well as a ¼” bead around each predrilled hole approximately ½” from the hole. For exterior installations, substitute clear GE Silicone caulk instead of glue;

(D) Carefully pick up, turn over and place tread on stair;

(E) Push down on tread to distribute glue or caulk;

(F) Be sure ends of tread are equally spaced on stair and that tread is pushed back as far as it will go against front edge;

(G) Using a shop vacuum, hold end of vacuum hose as close as possible to the predrilled hole(s) in the tread in order to vacuum up dust and drillings from hole and tread;

(H) Carefully drill the first hole toward the center of the tread;

(I) Vacuum out all dust and debris from hole;

(J) Screw in and tighten anchor. CAUTION: Using a power driver can strip the fastener. If you use a power driver, use the clutch to help prevent stripping;

(K) Drill and anchor another hole on either end of the tread;

(L) Drill all remaining holes and anchor them;

(M) Repeat the process for remaining stair treads.