Background: My home office area is carpeted, so many years ago I purchased, from Staples or Office Depot, a plastic floor mat, sold for this purpose, about 4' x 6', smooth on one side and with an array of sharp points on the other side. My desk-chair rolls on this very nicely, and the sharp points keep the mat where I want it on the carpet. Gradually depressions have developed in the mat, probably because the wheels of my desk-chair tend to rest mostly in the same place.
I'm looking for a way to get rid of these depressions, and for the mat to be flat again. My first (and so far, only) idea is to place it, smooth side down, on my concrete patio in the sun on a hot day - thinking that the heat might cause the mat to return to its original shape.
Any other ideas or experience out there dealing with this problem?
Thanks.