There are five types of carpet padding, rebond, felt, rubber, jute and wool. A rebond pad is most commonly used in homes and is a pad bonded from chunks of foam. Felt carpet pads are most widely used in commercial settings; the pad is made from bonded pieces of cotton. A rubber pad is the most expensive pad and has the shortest lifespan. It soon becomes brittle and turns to dust. Like felt pads, jute pads are most commonly used in commercial settings, and are an environmentally friendly option. For homeowners who are sensitive to chemicals and don't mind the expense, a wool pad is a good option.
For pets that infrequently wet the carpet, a rebond padding with moisture barrier is a good option. The moisture barrier helps to stains from penetrating to the subfloor. Some manufacturers also make their padding with an added odor guard to help further protect against the lingering scent of pet urine. It may be worth the extra expense to buy an upgraded pad that will not require as much cleaning, but will provide some protection from accidents that do occur.
For pets that wet the carpet frequently, a basic rebond padding without a moisture barrier is a good option. It is less expensive than the rebond pad with moisture barrier. The savings in expense allows the homeowner to replace the heavily soiled carpet and pad as needed.
Regardless of the type of padding underneath the carpet, exercise care with the carpet to prevent excessive damage to the padding. Immediately clean and deodorize urine stains to lessen their impact.