It is required that the cushion conform to carpet manufacturer recommendations for the specific product being installed. Failure to follow these recommendations for cushion may void manufacturer warranties. These recommendations may differ, depending on the style and construction of specific carpet. Cushion thickness for Residential carpet installations should not exceed 7/16 inch (11 mm).
Install separate carpet cushion in the longest continuous lengths possible, with cushion seams placed at right angles to carpet seams, or offset at least 6 inches (150 mm) to one side. Trim cushion flush with the inside contour of the tack strip and securely fasten to the substrate using staples or nonflammable cushion adhesive at all seams and around the perimeter of each room. With the exception of fiber cushions, secure seams with appropriate vinyl-coated cloth cushion tape per the carpet cushion manufacturer’s recommendations.