Installation Guide

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16.5.1 Using a Mechanical Stretching Device (i.e. Power Stretcher) is Mandatory.
Devices used as a substitute for, or an attachment to such devices that penetrate
through the carpet backing may cause injury, damage carpet or substrates, or
result in inadequate stretch. Such devices are not acceptable.
Mechanical stretching device – A tool used to stretch carpet during the installation
process. This tool is commonly referred to as a “power stretcher” or “carpet
stretcher” and can be found in a number of forms. This tool should have all of the
following:
1. A method to positively engage the carpet without slippage or damage –
usually a pin plate or similar structure commonly referred to as the “stretcher
head”.
2. A method to bridge between the “stretcher head” and a stationary structure –
usually an opposing wall. This is typically a group of adjustable metal tubes
ending in a padded plate.
3. A leverage or other type device that is capable of either supplying its own
force or multiplying the force applied by the installer. This force is required to
be sufficient to allow the carpet to be elongated by the amount required for
the carpet being installed.
4. A method by which the elongation achieved can be locked and held in place.
16.5.2 Amount of Stretch – Due to the difference in carpet backing types, it is required
that manufacturer recommendations for carpet stretch be followed. In the
absence of specific recommendations, tufted carpet with synthetic backing should
be stretched a minimum of 1% in length and in width. Patterned carpet may
require additional stretch to obtain pattern match.
16.6 Finishing at Wall– Finish the installation along the wall, leaving a smooth, neat
and secure transition. Trim carpet without damaging baseboards or moldings,
leaving sufficient material for backing to be securely tucked into the gully without
protruding face or backing yarns.
16.7 Transition Molding – Where carpet meets other floor coverings create a smooth
transition and adequately protect edges with a transition molding that meets all
carpet manufacturer and ADA requirements.
CAUTION: Failure to mechanically stretch a carpet may result in:
• wrinkling and buckling over time
• localized damage to the carpet
• delamination
• Wrinkles and buckles most often are caused by: failure to adequately
stretch carpet using a mechanical stretching device, using inappropriate or
improperly installed cushion, adverse temperature and humidity
conditions, or inadequate conditioning time.