Carpet Tile Defects

p_SCF_180_03Carpet Tile Defects Associated with Installation and Manufacturing
By Ray Darrah

Carpet tile is commercially used due to the ease of replacement and repairs. The
convenience of replacing worn, or damaged, areas in commercial settings saves time
and money, not to mention eliminating the inconvenience of having offices and workstations
in disarray with a full flooring replacement. The Carpet Tile concept has caught on with building
and business management companies with architects, decorators and designers eager to
specify carpet tiles with company logos, or patterns, using the expansive array of designer
colors and textures now available.

With the increased use of carpet tiles comes the increase number of tile failures due to
either manufacturing deficiencies or installation errors. The major players manufacturing
Commercial Carpet Tiles are Milliken, Mannington Mills, Designweave, Lees Carpets, J&J
Industries, Mohawk Commercial Carpet, Mohawk International, Shaw Contract, Masland,
Endura, Interface and Eurotex. The small specialty manufacturers are located throughout the
world adding to the number of manufacturers, but produce a small percentage of the installed
sales in North America.

Carpet tiles, also called Modular Carpet, are manufactured in broadloom widths then cut
into squares using sharp knife blades set in a template, cutting the carpet into squares from
the back side, or upside down. Cutting into tile square often results in cutting the tips of the
pile leaving edges fuzzing and is characteristic of longer, higher pile, textures. Cutting Saxony,
or cut pile, fabrics, leaves pile heights cut shorter at edges leaving joints visible and is also characteristic of carpet tiles, not a defect. Cutting the top of the yarn at leaves seams visible,
but no structural damage shortening the life of the product is evident.

The structural components of modular tiles include the yarn tufted into a woven substrate
that is adhered to an engineered backing system. The two primary components are the yarn
into the tufting substrate and the backing. The backing systems vary with each manufacturer
but are engineered to offer dimensional stability, superior tuft bind and minimize edge ravel.
The engineered backing system is the core structure allowing carpet to be cut into squares
and installed without edges lifting, raveling or loss of dimensional stability.

Manufacturing decencies are usually not detected until the carpet is in use. Should tiles
cup, edges lift equally on all sides, edge ravel and delaminate with backing systems coming
apart a manufacturing defect is likely. Tiles must be stable and all components must be equal
in dimensional stability for tiles to achieve structural balance. Edge lifting, cupping and edges
curling are symptoms of inadequate dimensional stability.

Edge curling, cupping and de-bonding of tiles could also indicate an installation or
environmental issue. Concrete sub-floors are to be tested to insure low concrete vapor
emissions and the specified adhesive, and adhesive spread rate, is required to eliminate
the installer and the site conditions as the failure mechanism.

The most common installation errors result in de-bonding from the sub-floor caused by
use of non-specified adhesives or improper trowel size and uneven appearance resulting
from improper floor preparation to bring the sub-floor into flatness requirements.

Excessive Concrete Vapor Emissions cause the most devastating failure in new
construction buildings and do so often. Fast track building and poor scheduling by the
construction supervisors leave the building and concrete sub-floors inadequate time to dry to acceptable vapor emission levels. Flooring experts and inspectors are often called in to
inspect these failures only to learn the tiles, or other flooring materials, were installed before
the windows were installed or the environmental systems operational. Buildings and concrete
sub-floors cannot dry to acceptable levels without the building envelope completely enclosed
and the environmental controls operational and in use for at least two weeks prior to installation of flooring materials.