How much shrinkage on designer cottons on a finished quilt.I am making
 

How much shrinkage can I determine on completed lap quilts that I may wish to sell in the fall. For example Moda cotton front and back and 80/20 batting if washed on cool gentle was and dry. I do not want to pre wash , prefer to display the new crisp look.

I never measure a quilt before washing. Maybe someone else has.

What does the batting say is it's percentage of shrinkage? Probably the only indication. I can't imagine more than an inch or two but I could be wrong.

It really doesn't matter if the fabric is Moda, Benartex, Hoffman, Kaffe..... Cotton fabrics shrink some. Lots of things determine the amount of shrinkage, the batting, the fabrics, the amount and style of quilting all play into it and each one can turn out differently. You could prewash your fabrics then spray them with sizing ( which you wash out when you prewash & is used to give them that look you seem to like) or starch. Or, you could make one, wash it & see what happens. Or, use polyester batting that doesn't shrink & heavily quilt to keep the fabric shrinkage to a minimum.

I know they shrink some, but have never thought to measure before/after. I don't like the super crinkly look, so for this reason I prewash all my fabrics and cotton batting before cutting/sewing.

The first time I presoaked Hobbs Tuscany silk batting (twin) I measured before and after; there wasn't much shrinkage widthwise, but it shrank about 5 inches lengthwise as I recall.

Warm & Natural says 3-5% shrinkage & that seems about right. Of course, it greatly depends on how heavily you quilt. I did one a while ago without pre-washing & I think I measured that it shrunk a little over 2". It was very loosely quilted.

I defy anyone to predict with any accuracy whether the fabrics in a finished quilt, made with good fabrics, have been pre-washed.

Take a piece of fabric - measure it - wash it and remeasure and you will see how much it will shrink when finished. Also remember batting shrinks too.

Also remember that quilting will 'shrink' the overall size before the finished quilt evers hits water and will additionally, as already mentioned, have an effect on the amount of shrinkage when washed.

May I ask why the shrinkage amount is something you need to know in advance?