Does anyone know how much fabric you need for a King back? I'm using 108 inch wide
 

Can't find measurements anywhere. Does anyone know? Thanks!
Susie

Not all Kings are the same. Can you please give us the measurements of your particular quilt? Then we can help you determine how much you'll actually need.

Around 120 by 120, thanks!

Here's a calculator that might help you.

http://www.quiltersparadiseesc.com/C...Calculator.php

That helps a lot, thanks!

If you prewash, backing fabric will normally shrink up to around 104", and then removing the selvages and allowing for seam allowance, you'll have more like 102" for usable width.

Sometimes I'll use an inset of regular width fabric in the middle of the extra wide to get it even wider.

An orphan block opportunity. Or the scraps from the front. Or coordinating colors you want to get rid of. You will ne e more than a single width, so get creative.

I'm making a Log Cabin- 12 inch blocks. Have no clue how to figure how many blocks I need. This is the part of quiltmaking that is a challenge for me :)
I bought 5 yards of 108 wide backing. Now to figure how many blocks........... I've made 27 so far and am really happy with the way they look.

If your finished quilt is 120” x 120”, AND your finished blocks are 12”, 10 blocks across by 10 blocks down will be 120” square. So 10 blocks across x 10 blocks down equal 100 blocks needed. If you add a border, you will have to refigure your calculations.
On the 108” wide backing, like Macybaby mentioned in post #6, you’ll have to add width to make it wide enough. You can add a strip vertically to make the width you need. (You’ll have enough length, because 5yds x 36” per yard equals 180”.) long arm rule of thumb is that your backing and batting should be 3” larger on all sides, or 6” across one side. 120+6=126. If you have other questions, just pm me and I’ll be happy to help.

How are you quilting it? If sending to LAQ you need to check with him/her but most want 4-6" extra on all sides. If quilting yourself on domestic, then about 2" on all sides. If you are quilting it densely, then add extra on all sides as the dense quilting will "shrink" it up more. So measure your quilt and go from there.