Ridge Beam Support

[hayeska]

I would like support a ridge beam (wood) in a CMU pocket. The CMU is reinforced and is also the wall of a fireplace. This is new construction. CMU/Veneer is on an exterior gable wall; ceiling is vaulted, fireplace is 7' wide through roof. The support location is 12' above the firebox. Code requires 2" clearance at sidewalls, 1" clearance through roof, and allows combustible materials (mantle & trim) 12" from firebox. I am looking for opinions regarding the code and clearance to combustibles.

Thanks

 

[ctcray]

With the chimney so big, and presuming it's designed and detailed to be a structural support for the load of the ridge beam and as long as you're well clear of the flue, I don't think you have a problem. My interpretation of those clearances is that they are more intended for smaller chimneys -- an 8x8 flue liner surrounded by 4" brick, for example. Seems every jurisdiction around me has a different interpretation of these clearances, though.

 

[hayeska]

CTCRAY,

Thanks for your response.

In the IRC 2006 Chapter 10 R1003.18 Exceptions 2. states that combustibles cannot be in contact with the masonry less than 12" from the flue lining. My clearance is greater than that.

I anticipate questions from local code officials when submitted. I am hoping to have enough convincing information. Often interpretations are subjective.

 

[MiketheEngineer]

Wood on concrete usually has to be treated....

Might need a steel shim between CMU and beam.. Check your local code.

 

[hayeska]

MiketheEngineer,

I plan to anchor the beam with a steel bearing/connector to the bond beam at that elevation.

Thanks for the response.

 

[DonPhillips]

It may be worth a call into the building official/plans examiner to discuss your interpretation - especially if you can fax in a sketch so they can see what you are talking about. Gives them time to think about it and look it up in the code before he or she gets back to you.

Don Phillips

http://worthingtonengineering.com