Beam for garage attic storage

Firenut | Posted in General Discussion on March 16, 2022 06:28am

Hello, I have a 26′ x 34′ garage with conventional rafter framing. The garage has 2 x 6 ceiling joist and 2 x 6 rafters spanning the width of 26′. I would like to take advantage of the attic for storage. I have a bathroom and craft room supporting about the first 10′ for storage. The ceiling joist span 25′ 5″ clear span, leaped joist in the center. The I-Beam would clear span 22′ 9″. One end would set on the back wall of the bathroom with solid blocking to the floor. The other end would set on the front wall of the garage with full solid blocking down to the footing. The maximum headroom in the attic is 4′ 6″ at the peak. I have found a used I-Beam for sale in my area that measures 4.5inches x 10 inches 3/8″ steel, curious if this would work for the span with no post. The beam is 30′ long, which I would cut to length and they are asking $800 dollars. Any help on whether this will work would be greatly appreciated. Thanks

Replies

andy_engel | Mar 16, 2022 07:02am | #1
There are beam span tables to be found online, or you can hire an engineer. They don't cost much. But more importantly, how are you going to install said I-beam? It's going to be very heavy.
krzelle | Mar 17, 2022 12:39pm | #2
You need to get an engineer involved to properly size the beam and determine if the used one that you found online is adequate for the present loads. Using online beam span tables are only helpful if you've accurately calculated the dead/live loads that will be imposed on the beam. Additionally, your local building department will likely require that a selection sign-off from a licensed professional engineer.
sawdust_steve | Mar 17, 2022 04:15pm | #3
Most decent lumber yards can do a load calculation for the support beam, if you walk in or give them a sketch of the condition
ct_yankee | Mar 17, 2022 06:06pm | #4
Best if you get a structural engineer involved.
Will all loads be transmitted to a foundation wall or footing?
Will the load(s) be transmitted to the floor slab only? This could be a problem.
Your 'word picture' requires some assumptions - perhaps a sketch might help.
meharg1 | Mar 18, 2022 11:35am | #5
You can find beam span tables online or contact an engineer. They are cheap.