Sewing question
 

I started looking for twin bed mattress toppers for our RV. A neighbor is getting a different guest room bed & she’ll have an extra 3” Queen topper which she will sell to me. It’s from Costco so barely used & I know it’s clean.

If I cut it exactly in half, it will work perfectly for my twin beds. It has a thin cloth cover which I want to preserve but after cutting, the foam will be exposed along one side and I need to enclose it. Any suggestions or ideas ?

Binding or facing. Since it's along one side, it shouldn't be too hard.

Sew or hand stitch a piece of fabric the width and length of the topper on the exposed side. Or if you want to go all out make a new cover. If I lived close by I could do it for you.

The cover for your topper should have a bit of give in it so you may be able to sew it down the side and it will fit. But before I do that I would try it on the 1/2 of the topper you cut to insure it will fit properly. If not you could still cut it a bit larger and sew down the exposed side. You would then have to make a second one. Now this I have had to do and I took 2 older twin top sheet and sewed two sides, bottom and one longer side. I then placed the topper in the finished sewn sides, measured and sewed the 3rd side to make it like a large pillow case.

Are your twin beds the standard 39 inch width? Or are they narrower?

Some toppers are a bit smaller than the actual top of the mattress - so that it might be only 58 inches wide - and when cut in half, that would only be 29 inches wide per piece.

Usually a king is equal to two twins.....I don't know about halfing a queen...I would check all your measurements.