Is the carpet a permanent fixture?

We have hardwood floors. Rugs go in places where softness and warmth are desired, such as the sitting room in front of the sofa, not in high-traffic areas such as doorways.

The cats do exercise their claws on the rugs, but not enough to do them any harm. (They are sturdy Afghan knotted rugs.) Furniture is another story -- our green leather Lazy Boy settee was severely shredded within its first year.

Our problem is preventing the old tomcat from pissing on bookcases when we don't move fast enough to get the back door open for him. In our next house, the library will have a door that shuts.