Effects of Moisture on Materials (cont.)

Carpet

The primary goal in water damages is to preserve and protect the structure and contents.  One of the first concerns is water-saturated carpet and padding, where unique problems are encountered.

The vast majority of the carpets are tufted construction type.  In simple terms, the tufting machine operates like a giant sewing machine containing hundreds of needles side by side.  The pile yarn is threaded through the needles and then the needles push the yarn through a previously constructed primary backing sheet.  Loopers in the machine move close to each needle eye and engage the yarn.  As the needle is pulled out, a loop of yarn (or "tuft") is formed and held in place in the backing material.  The tufts may be cut, uncut, raised and lowered to form a variety of textures and effects.

The next step is to coat the primary backing with latex or thermo-plastic adhesive that permanently anchors the pile yarn in place in the backing.  A secondary backing, either Actionback (polypropylene) or jute is then applied, and both materials are laminated together with a latex adhesive.  The secondary backing adds strength and body to the fabric and improves the dimensional stability of the carpet.

The most commonly used backings are synthetic (Actionback.  A small percentage of carpet backings are jute.  Of the two, jute normally causes more problems, such as shrinkage, deterioration and growth of mold and mildew.  Synthetic backings are more likely to restore after a water damage.

Tufted construction presents two basic problems: backing separation and latex deterioration.  Latex is the adhesive material that holds the tufts in the primary backing.  It also gives the finished product additional weight and holds the secondary and primary backings together.  Latex starts to deteriorate as soon as it is put into service.  Just like automobile tires, rubber bands and elastic bands in clothing, latex breaks down from gases in the air, floor waxes, traffic and sunlight.  The latex strength of water-damaged carpet is temporarily reduced by 50% while the carpet is wet.

Latex is produced in several grades.  The better grades contain additives that slow the breakdown process.  Cheaper latex compounds have fillers that take up space but offer no adhesive properties.  The more fillers in the compound, the less adhesive power, and the sooner a breakdown will occur, causing a separation of the primary and secondary backings.  This breakdown usually will not e uniform, but appears in the form of "bubbles."  In many cases, deterioration is more apparent along edges where the carpeting is more exposed to gases in the air.  The separation of primary and secondary backings is called delamination.

Latex deterioration, which leads to backing separation, is often discovered when the carpet is pulled during a water damage.  Minor backing separation or delamination can be repaired by applying a coat of latex carpet glue on the back of the carpet, using a putty knife to push the glue through the backing into the old adhesive.  Carpet showing extensive delamination should be replaced.

Water damage to glue-down carpeting often causes bubbling.  Bubbling occurs due to loss of adhesive and is not a result of cleaning or extraction.  The strong possibility of bubbling occurring after a water damage should always be qualified with a customer.

Paddings

The common types of padding used today are felted, sponge, rubber, rebound (urethane pieces cut and formed together), prime urethane and bonded urethane.  The quality of a pad is determined by three measures:

1.  Gauge is the overall thickness of a pad expressed in fractions of an inch.  The gauge can range from 1/4" on some urethane and sponge to 5/8" for other urethanes.

2. Weight is determined for a square yard of pad.  This measure can range from 4.5 oz. for some urethanes to 100 oz. for thick waffle pads.

3. Density is the weight of a cubic foot of pad expressed in pounds.  This measure is normally used in urethane pads and can range from 1 to 8 lbs. per cubic foot.

Various situations require that padding be replaced rather than restored.  Some padding deteriorates once saturated with water and cannot be restored.  Some padding is inexpensive, and the cost of removing, replacing and reinstalling new padding is less than the added costs of drying with pad in place (e.g., extra drying equipment, increased drying time).  Padding must be replaced when it hinders proper drying of the floors.  After examining the condition of padding, water damage restoration professionals should follow the rule: When in doubt, throw it out!  Remember, though, to save a sample of the padding for the adjuster and customer to use for identifying the replacement type and value of the pad.  Place a 12" by 12" sample of pad in a plastic bag.