Expert: Bart Ogden - 10/8/2008

Question
Hi Bart, I have a ventless gas fireplace installed into a dog house that protrudes from the side of the house
keeping the fireplace flush with the wall.  The dog house is about 9ft high and 5ft wide on the outside with a
10/12 roof matching the house roof.  I want to pull the gas fireplace out, open up the dog house from the
inside creating an alcove (which will rise about 7ft high inside the house because the dog house is about 9 ft
from the outside ground level but our first floor is elevated about 18" or so above ground) then place a
vermont castings vigilant stove partially in the alcove and build a chimney which will go up through the dog
house roof and climb about 24 ft or so on the outside of the house.  

I have several questions:
1. When I reach the soffit on the house roof, which has about a 12 inch over hang, can I use an elbow kit to
simply pull the chimney away from the house and around the soffit or should I plan to go through the soffit?

2. The ceiling support kit that I'll have to use when I go through the dog house roof, is that enough to rise
another 24 ft above or should I plan to use an intermediate wall support?

3. I'm using SuperVent double walled pipe and although I have found it at a good price at Menards it is starting
to add up.  By the time it is all done I'll probably have spent around $1800 - $2000 on the chimney and alcove.  
Someone suggested that I might be able to build a masonry chimney for about the same.  I don't know
anything about masonry chimney's; how much would a masonry chimney cost (guesstimate), it would have to
rise about 33 ft from ground level.  I would then forget about the whole alcove thing.

Thanks
Alex

Answer
Hi Alex,

1.  Go through the soffit.

2.  You should use intermediate wall supports as recommended by the manufacturer of your chimney system.

3.  You can't build a masonry chimney for what you can install a factory-built chimney.

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

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