Advicefor material on making beanbag couch

Gotham

I couldnt find a DIY board.

So a couple of friends want to make a big bean bag couch for chilling out on.
The idea was to buy a load of foam packing stuff and encase it in fabric, but at this stage we're worried about the fabric material.
We need something cheap and strong, it's got to feel OK and I don't know how its going to cope with household dust/dirt/stains yet, but that's a factor.
Anyone know anything suitable? Or know any deals on said fabric?

Anything else you guys can recommend for the project is welcome.

looksee

Buy cheap, preferably cotton, fabric of any pattern, something reasonably tough that doesn't fray - curtain lining fabric works well. Make your bag, fill with polystyrene beads (insulating beads) then machine the opening firmly closed. Make sure there are no little holes anywhere in the seams.

Then make your cover using fabric that will be washable - look for a loose cover fabric - and using the same pattern as the liner - you do not have to make it any bigger. Leave a long seam gap and put in a zip (you can use velcro but it doesn't really work as well). Your inner bag will be a bit floppy - don't over fill it - and you can ease it through the zip gap.

Gotham

Good plan, we didnt think of having an inner and outer casing. Will be handy for washing in the future.
Thanks!