CMU crawl space
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This isn’t a ‘green’ building question, just a building question.
We are building a ranch home in climate zone 5 over a conditioned crawl space. The footings are 7′ below the sill plate. The crawlspace walls are CMUs. The planned poured concrete floor will be about 4-5′ below the sill plate. Does a CMU wall like this need a bond beam?
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Replies
Hi Alan -
Must admit I have never seen a bond beam in this application. I am not a structural engineer, so I simply looked up some definitions of bond beam (did not really find anything on GBA....).
This seemed like the best explanation of just when a bond beam is needed (https://www.concreteconstruction.net/how-to/how-bond-beams-are-used_o). It seems to confirm that you don't need one, BUT maybe in your reading of this resource and your deeper understanding of your project, you see the need.
Peter
No, you don't typically see a bond beam in this scenario, unless the structure above or seismic or soils or tie-in to other parts of the construction dictates including one, or if structural designer wants one!
I apppreciate the expedient responses.
Our plans actually call for concrete (10”) walls, but the foundation contractor is using CMUs (16”). The designer asked for a the bond beam. The contractor said we don’t need one, but we can have one if we want one.... and he quoted a price.
I’m happy to pay for something that is needed. My research said we didn’t. I figured someone here on GBA would know.
Thanks again!