what is the best kind of foam for outdoor cushions?
There is a product on the market called "Nu-foam" that is great for outdoor cushions. It doesn't absorb water and doesn't loose it's "bounce" after being left outside. I bought mine at Joann's Fabs....
Here is a link that might be useful: here it is at manufacturers site
I used that Nu-Foam in my computor chair when i re-did it.it didn't hold up very long,i now have a pillow on the seat of my chair,until i can afford to get a new one.
It might hold up outside as it probably won't get used as much as a chair inside does.
But for me,i'll never buy it again.JMHO
I used nu-foam on my love seat & it didn't last 6 months. I went back & got the green high density foam. I don't know about outside. I will never buy Nu-foam again. It was fairly expensive & in 6 months worse than the foam that had been in there for 20 years. The front edges of the cushions was down to about 1 1/2 inches from 4". Not something used for a family...just 1 adult.
Try a shop that does boat cushions. The foam they use is made to dry quickly.
Foam comes in a variety of different densities and quality can vary greatly. Density refers to "squishibility", the amount of compression the piece of foam will endure before you "bottom out"... how it feels when your bottom hits the base supporting the foam!
Only two types of foam will not absorb water. One is the ultra high density "closed cell" foam. The cells that make up this sort of foam are closed and this is FLOTATION foam. It's very expensive and it feels "hard" under your bottom. I've used the 1" and 2" extensively, and have only seen 3" on very rare occasions. If you want anything thicker you will probably have to glue different thicknesses together.
The other is RETICULATED foam. This is very firm under your backside although it looks rather like a dry "loofah". The whole idea behind it is that its cell configuration is so open and structurally strong that water tends to flow right through it. Its expensive and it's great. I've used it for my own outside furniture. It's available in 1-4" thicknesses, the price varies greatly as the thickness increases.
(I work for a marine canvas and awning shop).
Both types of foam cost A LOT more than the crap JoAnn's sells... . But it lasts a lot longer, too. The linked item is NOT foam. It's simply layered polyester "core". it has its place, but it ISN'T a true foam. So don't be confused.
I'm planning to recover our outdoor cushions. I want to replace the seat cushion because the ones right now are too soft. (You "bottom out" when sitting down)
If I use Sunbrella for the cover, do you think it would protect the foam to the point that I could use the cheap stuff from Joanns?
Zone 8grandma - in a word: NO.
Sunbrella is a wonderful fabric, but it is not a magic fabric. If you're going to put all that labor into cushion covers, get the right filler. Otherwise you'll be replacing the cushion filler in a few months anyway. Go to a good upholstery supply shop and let them guide you to the appropriate foam for your needs.
I used to upholster, and had several customers who wanted that Nu-foam crapola. I would agree to use it if they insisted, but refused to offer any warranty on my work. Sure enough a couple of months later, they'd be back wanting to buy a decent cushion.
Thanks and one more question. These cushions will be outside from late spring until fall. Then they will be stored indoors. Most of our rain is from about October through April. We rarely get snow. The chairs are on a covered deck. Would any of this make a difference?
You're right. This is going to be a fair amount of work and I'm going to be spending $$ on the Sunbrella. If I can get away with cheaper foam I'd like to, but I don't want to be dollar wise and pound foolish.
You might be surprised at how (relatively) inexpensive foam can be. Don't get it from a Michael's or JoAnn's fabric store - most of what they carry is both over-priced and crap.
I don't have a current price list (I retired, and now quilt), but an upholstery supply shop will be able to cut the foam to the exact size you need for possibly $30 apiece. (Maybe a bit more of course)
If the cushions are on a covered deck and not usually rained on, I'd probably for for a standard cushion foam, not the expensive closed-cell stuff. I've never used the reticulated foam - but my business was furniture, not boats and outdoor stuff.
Thanks again. I'm going to call the lady who did a great job reupholstering an antique chair last year and get a quote from her.