Should you buy new carpet padding when you buy new carpet?

Most definitely. Many people don't realize that dust, dirt, animal evacuations and spilled items sink down into the padding. Plus the fact the after years of use, the padding becomes more flat and loses the "cushion" feeling.

yes, I was just reading that there is one carpet pad that is really expensive that outlives the life of the carpet. Forget which one, but it's a very rare pad. Generally speaking, the carpet pad goes bad before your carpet and then your carpet starts to take the abuse, which causes wear. So if you are replacing carpet because it's worn out...you need a new pad. And get a good one so your new carpet will last longer. Just remember, a good carpet pad takes the abuse so your carpet doesn't. Your installer should explain to you what the best kind is for you.

Well from what I know the padding is what keeps your carpet from getting worn out fast. You should replace it and not with the cheapest one. Hope that helps

If the carpet needs replacing, odds are that the padding does too. Padding is pretty cheaps, so it's best to just do it.

yess ,for sure. If not it'll keep sliding :)

Yes. Whatever is spilled on the carpet also gets onto the padding. After a few years things can get funky.

There would be dust, stuff form spills etc on the padding too.. If the carpet is in great condition though you wouldn't need to replace.

yesssssssssss

It's not required, but as everyone else said it's probably pretty gross so yes you should