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walkereng
walkereng, Consultant
Category: Structural Engineering
Satisfied Customers: 2831
Experience:  Over 30 years of Structural Engineering experience.
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18ft garage door. Brick face, block walls. Flat roof. Beam

Customer Question

Hi, 18ft garage door. Brick face, block walls. Flat roof. Beam must support 3ft of wall above beam plus possible 3ft snow load.
JA: OK. Tell me a bit more about what's going on so we can help you best.
Customer: I'm sorry I forgot to include the question! Looking for I-beam size
JA: Is there anything else the structural engineer should be aware of?
Customer: Nope
Submitted: 11 months ago.
Category: Structural Engineering
Expert:  walkereng replied 11 months ago.

I can help

Expert:  walkereng replied 11 months ago.

Do you have any kind of sketch you can share with me to detail your roof member configuration?

Customer: replied 11 months ago.
Unfortunately, no. It is an older building and without tearing out the ceiling there is no way to tell. I am assuming 2ftOC steel truss.
Expert:  walkereng replied 11 months ago.

I have several questions:

1. What city and sate do you live in?

2. Do the roof members span from this wall to the opposite wall, and if so what is that span?

3. Is you roof a rolled roof and does it have any rocks on it?

Customer: replied 11 months ago.
1) Chicago.
2) 16ft span
3) layers tarred over, no gravel
Customer: replied 11 months ago.
Ooops! Trusses run other way. NO SPAN
Customer: replied 11 months ago.
I meant no additional span load on beam in question)
Customer: replied 11 months ago.
Again, I must apologize. My partner says he wants two 18ft doors and the other DOES have 22ft span truss load.
Expert:  walkereng replied 11 months ago.

I am headed out for a family dinner right now, can I get back with you in the morning?

Customer: replied 11 months ago.
Sure. Have a good night!
Expert:  walkereng replied 11 months ago.

Thanks, ***** ***** you in the morning.

Customer: replied 11 months ago.
Any more info needed?
Expert:  walkereng replied 11 months ago.

Sorry for the delay.

That is funny, I just opened your question to look at it and your comment popped up.

I am a little confused with your responses.

If the roof trusses/rafters run parallel to this new beam over your garage door opening, then the beam only needs to support the 3' of brick wall above it. If the roof trusses run perpendicular to this beam. then the beam needs to carry the 3 ' of brick and also 1/2 the span load from the roof? Can you tell me which case you have?

Not sure I follow the 18' opening, then two 18' openings and then you talk about a 22' span truss load.

Can you start your explanation over from the beginning?

I want to make sure I fully understand your configuration, before I size any members.

Customer: replied 11 months ago.
Sorry for the confusion. The TWO doors are going to be on perpendicular exterior walls.
One WITHOUT additional truss loading and
one WITH 22ft span trusses ending over the door beam.(Sorry boss updated plan)
Customer: replied 11 months ago.
I will get my hands on the actual print in a few minutes and get back to you. Stand by.
Customer: replied 11 months ago.
I'm kinda in the middle so bear with me...
Customer: replied 11 months ago.
Personally, I wanted only one door. ;-)
Customer: replied 11 months ago.
OK got an old print.
Chicago
Recap: One 18ft overhead exterior door. Brick face over block building. Flat roof, 2x12 16oc, tar over membrane no gravel. Beam set ~3' from roof. Roof joists run perpendicular to overhead door. Beam must support this load.Second door: One 18ft overhead exterior door. On perpendicular exterior wall. NO additional load from roof joists. (run parallel) ALL other details about building identical.
Customer: replied 11 months ago.
Sorry, door (1) has 20ft span roof joists
Customer: replied 11 months ago.
Hello?
Expert:  walkereng replied 11 months ago.

OK, thanks for the clarification.

I will run my numbers when I get home from the office this evening and get your your beam sizes tonight.

Customer: replied 11 months ago.
Thanks. Let me know if I can help you with any more info.
Expert:  walkereng replied 11 months ago.

I’d like to point out that a Professional Engineer’s standard of care typically includes a site visit to assess field conditions and get an overall understanding of the structure. This can obviously not be accomplished through the internet. The information provided here is meant for planning purposes only (general sizing and budgeting) and is based on the information provided by you. All loading cases considered are for vertical loads only, no lateral analysis has been completed. The information should be verified by a professional engineer who can visit the site to ensure that potentially important information has not been overlooked or omitted.

For Door #1, 18' beam with 3' of brick load and supporting roof rafters:

You can use a W8x24 (50 ksi) steel beam for your 18’ clear span beam. The beam is 6.5” wide and 7.875” deep. It weighs 24 pounds per foot of beam length.

For Door #2, 18' beam with 3' of brick load only:

You can use a W6x16 (50 ksi) steel beam for your 18’ clear span beam. The beam is 4” wide and 6.25” deep. It weighs 16 pounds per foot of beam length.

You will need to have a local engineer detail your connections, size your column supports, and determine foundation requirements.

If you feel you have received a satisfactory answer to your question, click the Rating button that is appropriate. Experts are credited for each adequately Rated answer they provide. If you have additional questions, please let me know. Thanks

Expert:  walkereng replied 10 months ago.

Let me know if you have any more questions

Expert:  walkereng replied 10 months ago.

If you feel you have received a satisfactory answer to your question, click the Rating button that is appropriate. Experts are credited for each adequately Rated answer they provide. If you have additional questions, please let me know. Thanks