Okay, so let's say my quilt is 76 x 90 (just pulling that out of the air, but it's close enough for example)

The backing I'm looking at is 108 inches. How many yards do I need?
I know this is a dumb question but there it is....

You need it at least 82" long at the minimum. I would personally buy 2 1/2 yards.

Thanks!!!! (Where did 82 come from?)

:?:

You add at least 3" to all sides of the quilt. If you are having someone quilt it with a long-arm you should have even more "extra" around the edges so they can load in onto the frame.
The extra gives you some space if the quilting shrinks the top up a little, you don't want the backing to end up slightly smaller than the front. I always add 6" to each measurement of the top.

It's important to have at least 6 inches of overhang all around the quilt. 76" + 6" = 82". The 102" takes care of the 90" with plenty to spare.

Gotcha!

D'oh!

If you are taking it to a longarm quilter, check with her/him - the person that did mine wanted 8 inches extra.

Good information!

thanks for the information!

Wow, we learn from each other!

I just read on another post where this quilter bought 108" wide and prewashed it. It shrunk 16", so make sure you take shrinkage into account, normally it does not shrink that much, but you never know, just do not be sorry you did not buy enough.