Expert: Bart Ogden - 8/11/2008

Question
Bart,

I know nothing about fireplaces so please forgive me if I provide too much or too little information.

We have a guest room with a Heat-n-Glo model #RHW41 woodburning fireplace with an exterior chase. The room is unusable in the wintertime due to the extreme cold emanating from the fireplace, chase and hearth. (Mountain home in Colorado where the winter daytime high may be only 10 deg F) We have cut a hole in the drywall above the mantle in order to see inside the chase and in the side of the hearth. This is what we know:

*The chase is insulated on the three exterior sides but not the interior wall that it shares with the bedroom. R value is unknown.

*The firestop is 4' above the firebox with a false ceiling. (This places the false ceiling at the ceiling height of the bedroom. We cannot determine if there is insulation above this or not.) This is a single story home without attic access to the space above this room.

*There appears to be NO outside combustion air kit. We cannot find evidence of it in the interior of the chase nor outside of the home.

*The bottom of the fireplace is positioned 18 1/2" above the floor.

*There is a hearth extension that extends into the room 2' and is 5' wide and 18 1/2" high (from the floor). Thus creating a "box" hearth in the room.

*There is no insulation below the firebox.

*There is no insulation in the hearth "box"

It seems that adding insulation to the interior wall and hearth would help but is there more that we should do or can do? Should we add an outside air kit? Again, this room has to be sealed off from the rest of the house due to the extreme cold that enters through this area. We need a solution and the others that we have asked have not been able to provide one. Can you help?

Thank you,

Shannon


Answer
Hi Shannon,

You can insulate the chase and the bottom of the hearth extension.  You shouldn't have to insulate the interior wall that it shares with the bedroom as insulating the chase should effective insulate the building envelope.

Depending your locale, an outside air kit might not be required, but it's always advisable to have one.

There will be a handle that closes the outside air kit when not in use.  If there is one installed, you should see a 4" round, typically silver, flexible tube going to the outside.

You can't insulate inside the cabinet of the fireplace on the top or the bottom.

Also, remember to close the damper if it's not in use.  That should help.

I recommend you contact a local CSIA Certified Chimney Sweep to do some on-site diagnosis of your problem.

You can find a CSIA Certified Chimney Sweep at www.csia.org.

Thanks for using AllExperts.Com and good luck with your project.

Sincerely,
A. Bart Ogden, President
Home Safe Hearth & Chimney, Inc.
Wichita, KS
Voice: 316-265-9828
Fax: 316-265-9890
www.homesafeks.com