Selection of a Steel Beam for a 2 storey residential building

9/24/2018 at 1:09:26 AM

According to Table 9.23.4.3. a W150 x 22 should work for you - allowable supported joist length is 4.9 + 2 storeys. When you apply for your permit the plans examiner should be able to check and confirm the selection.

9/24/2018 at 9:06:49 AM

Not so fast.

First, W150x22 I beam is not a common size.

Which source are you referring to 9.23.4.3 ?

How are the ends of this beam being supported.....hopefully not by it's top flanges.

And which building official would even be qualified to approve structural steel ?

Here in BC this would require a structural engineer.

9/24/2018 at 1:08:48 PM

This quote is from the 2014 Alberta Building Code (all Canadian Codes are based on the National Building Code and should be the same although the numbering may differ from province to province). Article 9.23.4.3. 'Steel Beams' reads: The spans for steel floor beams with laterally supported top flanges shall conform to Table 9.23.4.3.

This is a simple question that the first level of certification of plans examiner or field inspector will be able to look up in the Code book (Part 9 is the first thing taught).

Thank you for posting this question and making me open the book.

If I was interviewing a prospective general contractor this is an excellent sample question. Any reputable general should have a copy of the local (Provincial or National code depending on Province), and be able to find the answer without the need to consul others.

Ian Derksen

Safety Codes Officer - Building

9/24/2018 at 1:29:31 PM

Hi, concerning what size of Steel Beam is necessary for your span I would recommend talking to a structural engineer or contact the steel company that supplies the beams and ask them. Some of these companies have their own engineer. I would talk to an engineer and ask him if you could use laminated wood beams instead

9/26/2018 at 7:43:23 AM

When it comes to a structure issue the best way to do is to hire a structural engineer who will ran some calculations to figure out the safe beam size, you also have to apply for a building permit just to be in the safe side. Guessing or even un-professional advice will not help much