You can fill it with a setting type compaound like durarock.

wrote in message
...
My sheetrock is up, but the panels aren't all perfectly flush against
one another. In most cases where there is a gap it's 1/16 - 1/8, but
there are a couple seams that are up to 1/4 inch. What is the best
method to attack these when taping and mudding? Should I cut thin
strips of sheetrock and fit them in before taping, or will the taping
itself be sufficient to cover the seam? Any particular suggestions?
Thanks.