I am having a problem with my wall-to-wall carpeting and wonder if anyone else has ever experienced this. Our home is almost six years old and the carpeting keeps getting humps or ridges in it. The carpet is very dense and was very expensive. (I think we paid over $75 a square yard or square foot. I don't remember if it was by the foot or yard.) Everthing looked fine when the carpet was installed and stayed looking good until around the end of the second year, the carpet looked like it was expanding. (Some of the humps were so big that you would trip over them.) We waited a year to make sure that it had stopped "growing" and so three years ago we paid to have someone restretch the carpet. Two years go by and, you guessed it, the carpet starts getting humps again. I don't understand how carpet can still be expanding after six years. Are there any carpeting experts out there or someone who knows what could be going on?