what product to use for sheathing?

[harryc]

For my current addition project, I need to "pad" out a section of exterior wall on the existing house, about 3/4" to 1". On top of this I will install vinyl siding. The existing wall has no insulation, so I'd like to use something that will provide some insulating benefit. What kind of material would be best for this? I thought of those pink styrofoam panels, but am concerned with safety in a fire. The existing wall sheathing is 1x20 boards with significant gaps, so I am afaid of toxic fumes entering the rooms in a fire. Any advice would be appreciated. And I'd also like to thank you for setting up this website.

[Rich]

We're pretty proud of what we've got here on this website.. hopefully the traffic will begin to pick up soon which could free up more of my time to write more articles.

As to your question. There is a fibrous material that is called homasote board. Or at least it used to be called that. It's been quite awhile since I've used it. I believe it was 3/4" to 1" thick too. Ok I found their website..
www.homasote.com essentially it's a sound deadening, insulating, etc..etc.. product. The website gives a pretty good explanation of it.

[harryc]

Thanks. That looks like the right stuff. I bet they didn't have any problems getting that domain name, either. :lol:

[Rich]

haha.. Probably not.