Some ladies that demo at one of the sites I also demo at every summer make these. The backing is heavy canvas or denim, the squares are sewn kitty corner starting in the middle of the rug, or with the center row if it's square or rectangular. They use a zipper foot so that they can put the poly squares as tightly together as possible.

Annie

Thank you Annie. Do you know how much they overlap each piece and how big the pieces are. Do they purchase their backings or make them. I really appreciate any info you might have. thanks

The pieces aren't overlapped. They sew the first piece in place, then fold it over to one side. The next piece is folded along the diagonal, then butted tightly against the first piece. It's opened up and then stitched along the diagonal. You just keep doing this until the surface is filled. I want to say that the squares are about 2" on a side and they cut them with a pinking shears.

They make their own backings.

Annie

thank you very much, Annie. I'm going to give it a try.

I would really love to have this pattern if any one has it.
My great-great aunt who recently passed away made these rugs. I would really love to make some myself. I would need pretty specific instructions though. If available, could you email me a pattern to: tammyjane@bellsouth.net
Thank you, I hope I get it!!
Tammy :)

Google is your friend.

Here is a link that might be useful: Recycled denim rag rug

Thanks for that! I had a friend who made these and I have yards of polyester doubleknit to recycle. Thanks again.