# Removing a load bearing wall, adding a beam ?



## jlhaslip (Dec 31, 2009)

All of your questions need to be answered by a trained professional, ie: an engineer.


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## Aggie67 (Dec 20, 2008)

When your DIY plans involve structural changes, or if you're really not sure, or you question the methods of a contractor, calling an engineer really is the best thing to do. But "calling an engineer" can be a bit of a mystery for folks. Here's a little "de-mystification."

When you're at the point where you think you need help (or you're being advised to get help), you usually have three questions: how much more is this going to cost, how do I find the right engineer, and what exactly should I be looking for as far as deliverables are concerned.

Cost:
For something simple like a set of beam calcs, or an inspection for something you spot, or professional opinion on a buyer's (or seller's) home inspection, the costs are pretty much in the same neighborhood. A few hundred dollars. Not $100, but not $900. When I get calls, I have a spreadsheet that helps me come up with a fair number, based on many years of doing this. But local cost of living comes into play, and what you'll see as a fee in Montana won't be the fee you see in a Boston suburb. In your case, it would probably be in the upper part of that range, because it's a main element and the load path calculations for the whole house have to be done. Bottom line, that couple hundred absolutely guarantees that you're getting good information, from an experienced, unbiased professional. Plus the work is backed by liability insurance, and a state license.

How do you find the right engineer:
Not every engineer is licensed. Not every licensed engineer is a licensed structural engineer. But you need a licensed structural engineer. If you're into Google, do a search with the words (don't use the quotes) "your state", "residential", "licensed", "structural", "engineer". A positive sign would be if the engineer is a member of an association like NABIE, knows ASTM E2018, does structural inspections, etc. You should get a bunch of hits. You can also get the word out that you're looking for one, and someone you know at work or church or school sports undoubtedly knows one. 

What you should expect:
Expect a field inspection. Expect a short report with the recommendation. Expect everything to be signed and sealed. Expect plan view sketches of beam and support locations, with member sizes called out. Expect joint details and fastener schedules. Expect the calculations. Don't expect 24x36 blueprints, unless you ask for them. And expect them to be available throughout your project for phone consultations.

I hope this helps someone, someday.


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## Lakedriven (Oct 12, 2010)

*Thanks*

Thanks Aggie67. I kind of suspected this would be the path I would have to take, other than the OJT of a hardcore DIY'er. I appreciate the education and the De-mystification of the process. Thanks


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## acerunner (Dec 16, 2009)

you could probably use the span tables for this case, but it'll be over-engineered. Getting an engineer to do the appropriate calculations is the best option.

In case you're curious, the table would be in IBC "Table 2308.9.6 Header and girder spans for interior bearing walls".

edit: nevermind, the span table only covers up to 11'9" spans. so not applicable here.


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## Lakedriven (Oct 12, 2010)

Thanks acerunner. I've found similar tables in my attempts to educate myself. That table is one of the more user friendly and straight forward I've seen, thanks.


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## Jim F (Mar 4, 2010)

The 2x4's going from the wall at an angle to the rafters sound like part of roofing trusses.


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## Gary in WA (Mar 11, 2009)

There are a few problems with using the standard charts in your particular case. 
1.You have an additional roof load (the purlins and struts in the attic) as well as the ceiling load. Sounds as if your roof rafters were over-spanned for their size at the build, hence the struts to pass inspection by reducing the span. Do not remove them....

2. Many times when removing a big section of wall as you are, the S.E. calls out plywood shear panels replacing the drywall or plaster and lath on sections of the undisturbed wall, to make up for the big hole made (requiring extra bottom plate nailing). Otherwise the ends of the house may not have enough shear in them for their length. Drywall nail pops, tape cracking, etc.
Very important if you are in a high wind or seismic area. 

3. The attachments/strapping on both ends of the new beamis critical for shear flow to tie the wall sections together for structural strength. 

4. The post size is very important for the load, as well as the attachments to the beam.

5. The posts now bear on a beam below, changing that load from a uniform to a point load, increasing that loaded beam below. It cannot carry as much, depending on where the posts land and the closeness of the posts in the crawl. It may require additional footings and post.

This is why standard tables will not work in your case. Keep a paper trail (permit) for your H.O.Insurance carrier as you are now be liable for the safety and structural integrity of your work and possibly responsible after you sell the house.

6. Solid blocking is required in the floor below---- the only thing you don't need an Engineer for! 

Gary


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## steveel (Sep 10, 2010)

I'm going thru a similar project, only in my case we're repairing compromised members and missing loadbearing walls, not taking out working ones. Before the SE came over I mapped out the basement and first floor framing in the free version of sketchup. Turned out that was a big help.


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## Evil Scotsman (Nov 4, 2009)

Aggie67 said:


> When your DIY plans involve structural changes, or if you're really not sure, or you question the methods of a contractor, calling an engineer really is the best thing to do. But "calling an engineer" can be a bit of a mystery for folks. Here's a little "de-mystification."
> 
> When you're at the point where you think you need help (or you're being advised to get help), you usually have three questions: how much more is this going to cost, how do I find the right engineer, and what exactly should I be looking for as far as deliverables are concerned.
> 
> ...


It has and Thank You


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