You should be able to use 44" fabric for this technique, it WILL work. Don't be scared by the math, it's quite simple once you grasp the concept.

Pretend this rectangle is 44" wide. Not wide enough for your backing, right?
http://www.multi-patch.com/assets/images/Diagonal4.gif

Notice carefully what happens when you cut diagonally, slide the piece on the bottom left UP, and the piece on the upper right DOWN. The width of the rectangle (your fabric) gets WIDER.

http://www.multi-patch.com/assets/images/Diagonal3.gif

It also gets shorter, which you will have to take into account. But, this is a good, reliable way of making 44" fabric wide enough to use for a backing.

Also - when you go to Joann's (any fabric store), ask the employees where they keep the 108" wide fabric. I've seen it at Joann's.

There are lots of stores online that sell wide width fabric for backing.

http://www.fabric.com/quilting-fabri...Source=LeftNav

if you have a twin top-say 63" x 72" you buy 4 yards of fabric for your backing- cut it in half---now you have 2 pieces 72" x 40" (or so) sew them together---now it's 72" X 80"...Quilt your quilt trim to size, bind--and you have some scraps to add to your stash...you do not have to add borders if you don't like the look- do some math & buy what you need to make your back fit. or you can always purchase wide backs- they are available from 90" wide up to 120" ...some people like scrappy pieced backs- some like them to look whole. if you piece like the first example when it is quilted it is pretty much impossible to tell it's not a whole piece.

Thousandsofbolts.com has lots of 108" wide quilt backing material.

I use to work for an Interior Design workroom. When we made bedspreads and coverlets we would run 2 seams longways of the piece. We would center one width of fabric then split the other width and sew one on each side of the middle one. That stopped it from looking off center and made it very tailored.

You could also buy flat sheets to use for backing.

our group did a medalion quilt that just kept growing on the back we put in a band of fabric 6. wide off set to the left vertically and below center horazontally where they intersected we fitted a lable---it looked great

go to John Flynn's web site. I believe it is undr workshops. He has a method for piecing the back on the diagonal in which you add a certain number of inches to the length cut on the diagonal and then slide one side down to increase the width. It works great and sure saves fabric.

Here are few ideas for enlarging a regular size (44" wide) fabric backing.

Jan in VA