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Expert: - 1/15/2009


Question
We are remodeling and want to close off an unused chimney flue.  We are building a 2x4 wall across the flue and are putting sheetrock on the wall.  We need the flue sealed off. It is an 8 inch flue.  What is the best way to seal the flue opening? Also is it ok to completely seal off the chimney opening or will that create dampness within the chimney that cannot escape?

Answer
Hi Jerry,

I'm assuming you're referring to building a 2x4 wall across the fireplace opening, not the flue itself.

I don't recommend sealing the flue completely from the top and the bottom as it will typically cause condensation.

You can, however, stuff some fiberglass insulation into the flue from the bottom and this will suffice.

Make sure the top has a high-quality stainless steel or copper chimney cap installed to keep rain and animals out of the flue.

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

CSIA Certified Chimney Sweep #2653
CSIA Certified Dryer Exhaust Technician #10
NFI Certified Wood Specialist
NFI Certified Gas Specialist
NFI Certified Pellet Specialist
NFI Master Hearth Professional
NCSG Technical Advisory Council Member

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Bart Ogden

Expertise

I can answer questions related to chimney and fireplace cleaning, construction and repair as well as questions related to the performance of chimneys and fireplaces. I can also answer questions related to clothes dryer vent cleaning and repair. Additionally, I can field questions related to masonry repair.

Experience


Experience in the area:
28 years experience in the chimney service/installation/repair field
President, Home Safe Hearth & Chimney, Inc. Wichita, Kansas

Professional Organizations:
Member, National Chimney Sweep Guild (NCSG)
Member, Hearth, Patio & Barbecue Association (HPBA)
Member, Kansas Guild of Professional Chimney Sweeps (KGPCS)
Member, Midwest Chimney Safety Council (MCSC)
Member, Kansas Association of Real Estate Inspectors (KAREI)
Past At-Large Director of the National Chimney Sweep Guild
Past At-Large Director of the Chimney Safety Institute of America
Past Secretary, National Chimney Sweep Guild
Past Secretary, Chimney Safety Institute of America
Member, National Chimney Sweep Guild Technical Advisory Council
Member, Chimney Safety Institute of America Certification Committee
Past Chairman, CSIA Chimney Safety Education Brochures Committee
Past Chairman, NCSG Nomination Committee

Publications:
SWEEPING Magazine, The Journal of Chimney & Venting Technoloty, A Publication of the National Chimney Sweep Guild
SNEWS, The Chimney Sweep News
THE KANSAS SWEEP, The Voice of the KS Guild of Professional Chimney Sweeps

Education/Credentials:
BA, Wichita State University
C.S.I.A. Certified Chimney Sweep
C.S.I.A. Certified Dryer Exhaust Technician
N.F.I. Woodburning Specialist
N.F.I. Gas Specialist
Chimney Diagnosis & Documentation Seminar
Ahren's Masonry Restoration School Graduate
Advanced Gas Certification
Master Gas Certification
Licensed Mechanical Contractor
Pellet Appliance Specialist
Venting Design Specialist
Dale Carnegie Course Graduate

Awards and Honors:
Superior Dealer Award, Ventinox Chimney Lining Systems

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