Originally Posted By: pbennett1
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Cant seem to find anything on beams as far as the formulas, i.e., L/240 (ceiling joists) L/280 (roof rafters). Does anyone know?
Cant seem to find anything on beams as far as the formulas, i.e., L/240 (ceiling joists) L/280 (roof rafters). Does anyone know?
Originally Posted By: roconnor
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You can find deflection limits in the local codes or IRC, but those measurements and calculations are beyond a home inspection.
If there is clearly visible sagging or flex in the framing it is usually a concern that may need to be looked at more closely.
Just my opinion and 2-nickels ... 
--
Robert O'Connor, PE
Eagle Engineering ?
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NACHI Education Committee
I am absolutely amazed sometimes by how much thought goes into doing things wrong
Originally Posted By: ccoombs
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Beams would fall under the L/240 range (L/360 based on load combinations). However, this is a structural requirement. There are many conditions were a beam is within the L/240 range and would be a problem. We not only limit deflection to L/240 (or similar limit) but also to an actual amount. Floor joist are limited to 1/2" and beams to 3/4" in living areas.
I agree with Robert. If you notice the deflection and it is a concern, it should be reported and referred to an engineer.
--
Curtis
Originally Posted By: pbennett1
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The beam deflects by about 1/4" in 43.5 inches due to removed foundation material which seems to be an ongoing building practice in NJ. I always call this out, especially when there are joists on top of the beam, and the buyer tells me they have plans of adding a second story.