Installation Guide

Rev.1.12.09.10 10
4. CARPET TILE AND COMMERCIAL CARPET
4-A Electrical Rough-In: See section 1-A.
4-B Planning & Preparation: See section 1-B.
4-C WarmFlex™ Installation: See section 1-C.
4-D Fiberboard layer installation.
1. After laying WarmFlex according to section 1-C, you will need to cover it with one layer of 4’x8’x1/8”
fiberboard also known as medium density fiberboard (MDF) or hardboard. This will become a floating
sub-floor that will not be fixed to the floor below.
2. The fiberboards must acclimate to the room where they will be installed for 48 hours at 65°F or more.
3. The floor heat system must be turned off during installation of fiberboards and final flooring.
4. Leave an expansion gap of 1/8”-1/4” between the fiberboards and all walls around the perimeter of the
room and around pipes and other fixed objects. See note below.
5. Leave an expansion gap of 1/8”-1/4” between all fiberboards.
6. Fiberboards can be cut by scoring 2-3 times along a straight edge with a utility knife and snapping along
the cut line. This avoids creating dust that will impede bonding later.
7. DO NOT CUT FIBERBOARDS OVER THE FLOOR HEATING SYSTEM as you risk cutting the heating wires.
8. If installing carpet tile, the fiberboard must be laid in a diagonal pattern (see Diagram A) as follows:
a. Cut one sheet in half to 4’x4’.
b. Cut one 4’x4’ sheet in half diagonally so that it makes a triangle with 4’ on two sides.
c. The pieces cut in a. and b. above will be laid in one corner of the room so that the longest sides of
each triangle face the wall (see Diagram A pieces marked [1] and [2].
d. Repeat the process in a. and b. of cutting 4’x4’ triangular pieces as necessary to start each new row
(see Diagram A pieces marked [5], [7], [9], [15] and [16].
e. Lay fiberboard in sequence as numbered in the diagram so that the triangular pieces are laid first.
f. Be sure to maintain expansion gaps between fiberboards and fiberboard and walls as noted in
steps 4 and 5 above.
g. Use cut pieces and trim as required to fill in remaining areas (see shaded areas in Diagram A).
h. Duct tape the seams of the fiberboards to hold them in position while laying the carpet tiles.
4-E Floor Covering Installation:
1. Vacuum the surface of the fiberboards to remove dust before laying the floor covering.
2. For best results install the floor covering within 48 hours of laying the fiberboards.
3. The floor covering is to be laid onto the surface of the fiberboards without exceeding the edges of the
fiberboard.
4. Install flooring material as per flooring manufacturer’s recommendations.