Covering a Drywall Hole Around a Plumbing Pipe

If you have a plumbing pipe with an oversized hole around it, you can cover and conceal the drywall hole after the fact by simply getting a flexible silver finish plastic flange that has a cut in it that you can slide over the pipe.  You can glue or calk the flange to the wall if needed. This flange is available at most home stores - Make sure to measure your pipe carefully or better yet bring a small sample.