How Much Fabric to Get

The original poster is not answering questions. Though many were asked long ago, I am answering because it is a popular instructable and I have over 40 years of sewing experience.

It all depends on how wide the fabric is and how big you are. If you want to use woven cotton fabric, and have a bust under 40", just buy the length of fabric that you want to dress to be in length, plus some extra for the straps. If you are plus and your bust is larger than the 45" width cotton fabric comes in, then you would need to buy twice the length you want the dress. BUT you don't want to use both full widths across of 45" or it will be way too big and bulky. Unless you have an 80" or so bust.

Let's say you are a big beautiful woman and your bust is 55" and you want the dress to be 45" long. (I am 5' 4" and that is ankle length for me) A nice cotton fabric that's 44" or 45" wide will not fit around your bust (nor mine), so you must have TWO lengths of fabric, one for the front, one for the back of 45" wide fabric. to make a dress that will fit around your girls.

Oh, I hear you thinking. Why can't I run the fabric sideways? It's best to not try and fudge and run the long length of the fabric around you sideways. Garments should be made up and down the long length of the fabric, the way it comes off the bolt unless the Zombie Apocalypse happens. The manner in which fabric is woven makes it hang all wrong when it is hung sideways on a body. It won't look good or right.

So 45" length for the front, 45" length for the back, plus 4" for the four hems - a 1/2" one at the top and at the bottom (a double fold of 1/2" at the top and bottom of each of the two pieces means an inch gets used up at top and bottom of the front and of the back). (4 x 1" = 4"). Did that make sense? A half inch seam means that your fold over 1/2" of the raw fabric edge neatly, iron and fold 1/2" over again, iron flat, then sew it down. That's happening in four places.

You won't be using the full width of each 45" piece across your body so we'll have plenty left over for whatever kind of straps you want to make. Fabric is sold by the yard, but can also cut in one long length with an additional increment of a partial yard if needed. We needed 94" of fabric. Fabric is almost never cut exactly straight across at some stores, so adding a little might not be a bad idea.

94" is 14" less than 3 yards, so I would just go ahead and buy 3 yards. So any plus person with a bust over 40" or so wanting a 45" long dress needs 3 yards. Any person with a bust under 40" needs to buy whatever length of fabric they want the dress to be, plus maybe 4 inches more to have plenty for straps of whatever style you want. You CAN fudge most straps and cut them sideways on the fabric instead of lengthways if you are trying to be as economical as possible