Spray foam to sound deaden the doors

I was just wondering is it ok to use spray foam on the inside of the doors and the rear deck to kill sound? I was just thinking of going to the hardware store and picking up the foam they use as insulation.

Would this work OK? Should I also spray this foam in the trunk area where the spare tire sits?

I've heard of this before but I'm not sure how well it works. I'd suggest just playing it safe and picking up some Dynamat off of eBay.

get sound deadener self adhesive sheetsi.e. dynamat, brown bag, or equivelant, spray foam really hard to clean up if gone wrong.

This foam might also work to fix the H/K (Harmon Kardon) rear deck rattle. I'm not sure how dense the foam is or how big it expands to. I also don't know enough about the rear deck cavity. I'd hate to spray the foam and have it leak through.

Don't use expanding foam !!!

Expands everywhere and can flex panels if it can't find anywhere else to go. Sticky as hell, if you get on any upholstery, almost impossible to remove.
Also, when you talk about sound deadening doors, remember to allow drainage holes etc space to still run clear.

There are many brands of self adhesive "bitumen" based dampings available but for sheer workability and performance in a single layered application, the Dyamnat Extreme is hard to beat. Not cheap but you'd need to use a couple, of layers of most others to compare the performance and that just takes more time in the long run thus resulting in no major saving.

You could use foam to fill some of the unused voids over the rear wells etc. but I'd recommned sprying it into a bin liner of some sort to allow it to be easily removed should the need arise. If you're going this route, have a spray bottle of water around and inject some foam, then some spray water, more foam, more spary water etc. The water actually helps the foam to cure thereby stopping the middle from staying a gooey mass.

the spray foam works well, especially in hard-to-reach areas where dynamat wouldn't work or would be a pain to install.

However be aware of the rubber smell that can last up to a MONTH (especially if theres a lot). Since I used mine in my doors, it was extremely strong.

If you can, just stick w/ dynamatt.

Originally posted by drgalleg
the spray foam works well, especially in hard-to-reach areas where dynamat wouldn't work or would be a pain to install.

However be aware of the rubber smell that can last up to a MONTH (especially if theres a lot). Since I used mine in my doors, it was extremely strong.

If you can, just stick w/ dynamatt.

What type of foam do you recommend?

I used the dynamat version of it - can't remember the name. Another that I've heard works well is cascade audio's foam.

Originally posted by daz



What type of foam do you recommend?