Has anyone used the water heater insulation that you can buy at one of the home improvement stores to insulate a firewall? I am ready to install my a/c and I want to insulate the firewall the best I can. I have the original firewall pad in there now, but I'm wondering if I can do more. I would be interested in using this behind the rear seat and coveing it with the original pad also.

I had a small gap around my steering column and I could feel heat coming through and I sealed that up last night with the expanding foam....no heat coming through now. Any ideas or suggestions would be greatly appreciated.

Hmmm, I'm not sure that water heater insulation would work so well. The best and most commonly used is the Dynamat or Hushmat followed by the firewall installation pad. Another thought might be using window falshing tape from the home improvement store then followed up with the firewall insulation pad. The flashing tape is a Butyl-rubber and aluminum facing much like the name brands listed above with a adhesive backing. A lot cheaper. Anyway some food for thought.

Best Regards
Randy

Brian, don't use the expanding foam it will deteriorate and the flexing of the floor will cause it to crumble.

Thanks for the info. I appreciate it and I'm looking at buying some Dynomat from my neighbor...it's a new roll that he never used.