we need to select the kind of foam and specify a type of fabric.
We assume these cushions could get wet, occasionally.
Thank you for your help.
are we talking interior cushions or exterior cushions?.....
i am assuming you are meaning interior cushions, and if so, any synthetic automobile fabric is an excellent product for the interior. you have many more patterns to choose from, its highly UV and fade resistant, it takes the wet just fine and it dries reasonably quick depending on what type of nap it has....
the only thing sunbrella type fabrics have over the synthetic automobile fabrics is that they are made to shed water better and some types are actually waterproof. but for longevity in the sun, a quality car fabric will be about the same.
for exterior I would recommend the sunberlla type material, only because it has no nap and will dry out quicker than a nappy automobile fabric.
there are several different brands on the market now that are equal to or surpass sunbrellas quality, but sunbrella is the most famous name, and its such a close difference that it dont really matter what brand you use.
For the foam, you will be disappointed with anything but the "restaurant grade" stuff. its almost the perfect density for settee cushions in the 3" thick stuff...