Shrinkage is a factor in planning how much fabric you need for a project. To help you, we took a 1/2 yard of every one of our fabrics, measured the length and width, washed it in a machine with very hot water, dried it in a dryer set on very hot setting, and then measured it again.
Then we calculated the % shrinkage in length and width which we are reporting to you.
Please be absolutely clear!
We think it's the worst case scenario.
This is only our experience and yours will vary.
Please do not take this as some sort of guarantee about how much the fabric will or will not shrink in your circumstances.
Most fabric shrinks when washed and dried, especially undyed fabrics such as the ones that Dharma sells. Fabrics that go through a dyeing process will also go through a shrinkage process. Dyed fabrics that you would normally purchase in a fabric store have already gone through a dyeing process and therefore have gone through a preliminary shrinkage process. So when you buy undyed fabric from Dharma, you're buying fabric that has never been shrunk.
Reasons to preshrink fabric:
Tightens up the weave so it will make the fabric denser and therefore more opaque. For sheer chiffons and gauze fabrics, tightens up the weave and makes the fabric more crinkly. Also softens up the fabric.
Assures that what ever you sew or construct (if not dyeing the fabric) will stay the same size after the first washing. Fabric shrinking after garment construction will result in distortion and puckered seams.
Removes sizings, surface treatments, skin oils from handling, invisible dust and visible dirt to ensure a perfect surface for dyeing and painting.
Pre-shrinking is also very important if you are using paint or heat transfers on fabric, so that you don't get weird puckering around the paint or transfer after it is washed.
Using laundry soap or detergent takes out the fabric sizing that some manufacturers use. Removing sizing from fabrics is also better for your sewing machine and makes the fabric easier to work with. Zig zag or serge the raw ends of the fabric to prevent it from fraying.