Common Rug Problems You should Know About
Ripples
If two adjacent areas of a carpet or rug are not manufactured under the same amount of tension, unevenness or rippling can develop.
Each case of rippling is different. 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. However, the ripples may recur when moisture is again present.
For rippling in wall-to-wall carpets, please see Common Carpet Problems-Ripples.

