Ripples

Carpeting, like most other textiles, is made under tension.  Tension is necessary so that the loom will function properly, producing a carpet uniform from one portion to the next.

Yet carpeting differs from most textiles in that the backing may be composed of several layers, which are not generally preshrunk.  When backing yarns absorb moisture, the fibers swell, resulting in the relaxation of the yarns previiously held under tension.  Moisture which produces swelling may result from humidity, spills or cleanng.  When the humidity is back to normal, or the carpet is allowed to completely dry after cleanig, the carpet will typically go back to its' normal tension and not have ripples.

If two adjacent areas of a carpet or rug are not manufactured under the same amount of tension, unvenenness or rippling can develop.  This will also occur if the tension of teh second carpet backing is not uniform wilth the primary backing.

Each case of rippling is different.  The ripples may extend across the entire width of the carpet, from the edge to the middle, in the middle only, along the edges, or in one small section. 

For area rugs and oriental rugs this situation can sometimes be corrected by wetting the backing and tacking the rug out in a stretched position.  Ripples can also be caused by dragging heavy furniture across the carpet or by sliding and pulling of carpet in traffic areas caused by walking.  Improper installation may also cause ripples.  Installation over padding is best done by power stretching to make sure that the carpet is stretched tight initially.   

 ASCR International