Installation Guide

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Note: Carpet placed into transition moldings requires edge sealing to prevent raveling.
17. Carpet on Stairs
17.1 Preparation – It is required that the stair tread, riser and stair nose should be
clean, dry and structurally sound. The stair nose return should be rounded ¾-1
inch (19 to 25 mm) to prevent sharp stair edges from cutting carpet and/or
cushion, and to provide proper carpet contact for adhesive installations. When
carpet is installed over a separate cushion, extend the cushion over the stair nose.
17.2 Stretch-in Installation - Tack strip is to be installed on each tread. It is required
that pins on the tread point toward the riser. On a waterfall-type stair installation,
tack strip is to be installed on risers also. Pins on risers point down to the tread. It
is required that the gully between strips be slightly less than double the carpet
thickness. Where a turned finish is desired, tack strip and cushion are about 1½
inches (38 mm) less than the carpet width, to allow for a turn under on each side
of the stairs. Some stairs require tack strip on the sides to maintain the proper
tension. When using a cap-and-band or contoured technique, tack strip is not
used on riser.
Note: When staples are used in upholstering carpet on stairs, take care to separate pile yarns
to avoid trapping yarns, resulting in visible distortion. If the edges are cut net, they must be
sealed. Upholstery work needs to have no raw edges exposed. Any seams or joints must be
sealed. Carpet seams need to be split in the direction of the balusters.
17.3 Glue-down Installation – Install carpet on stair treads and risers using
recommended adhesive. Stairs without a return (nose) can be installed as one piece
over the tread and riser. It is required that on stairs with a return, carpet be cut and
installed with the tread and riser being separate pieces.
17.3.1 Carpet Direction –It is recommended that carpet be installed parallel to length of
stairs.
Note: Most manufacturers recommend carpet pile direction run down the stairs.
18. Modular Carpet
Follow carpet manufacturer recommendations regarding application, squareness and
location of working chalk lines. Install modular carpet on 90º format with corners
aligned according to manufacturer specifications. It is required that installation
geometry (monolithic, ashlar, quarter turn, etc.) be agreed upon by all parties prior to
installation.
18.1 Joints – Modules in the completed installation should be tight but not compressed.
To insure proper spacing when installing modular carpet, measure the distance
covered by 11 modules (10 joints) installed on the floor with no visible gaps, peaks or
overlaps. Continually check that modules are being installed in compliance with
manufacturer specifications for that particular product. Take care not to trap yarn
between modules.