SPE Help

[rigidpsycho]

I was wanting to make my own SPE. I have a full length 20" wide x 1" thick self-inflating pad I bought at Target. I was wondering how much material and what kind(i.e. sil or untreated)would I need to make one?

[Dutch]

I made two so far. They are really easy to design for yourself. One has two compartments on one side and one compartment on the other. My second one uses tapered extenders that are wider at the top (about 6" and are about 3 inches at the bottom). Now to answer you questions I don't think you want anything treated with sil or DWR at all. You want moisture to pass and move away from your body. I used some cheap nylon that was light and pleasing to the eye. For the amount it depends on the size of the extenders. Let's say you use 8 inch extenders on both sides. Than you will need 20" for the body plus 16 inches for each side and about 5 inches for seam allowence and to make up for the width of the pad. 57 inches should do it or 2 yards. Or get 1 yard of something 60 inches wide. Don't forget the elastic on the back or you will need another 20 inches.

I left an inch and a half flange on the back to make it easier to slide the main pad in. I hope this helps.