Architecture/support beam


I have seventeen foot span that I need to support so I can take a kitchen wall down. Above the span will be 2x10 joists that go 12 feet in each direction (24 foot foundation.The floor above that has three bedrooms and one bath, with a hallway wall directly above where beam will go.I was wondering LVL or steel.Smaller is better.


In this particular case, a wood beam consisting of three 1-3/4" x 14" LVL 2.0E would be better than a C15 x 33.9 steel beam for two reasons:

1) Wood framers are often intimidated by steel beams and thus will charge much more to install.

2) The LVL beam will cost you $180 for material whereas the 15 inch deep steel channel with a length of 17'-9" (4-1/2" bearing on each end for a total opening width of 17'-0") will cost you approximately $600.  In other words, the steel beam will cost three times as much as the wood LVL.

The labor to install either beam should be approximately $200 but again, some people will charge much less to sink nails into the wood beam compared to those who simply do not feel comfortable installing a steel beam.

I would expect both beams to deflect approximately 1/2" inch - which should be considered as an acceptable amount of sag in the middle of the beam.  I am assuming that you have 8 ft high ceilings in the lower level and therefore the beam depth is going to be limited to something less than 15 inches.  Otherwise, the height of the opening below the beam is going to be less than the code-required minimum of 6'-8" for head room under the beam.  And let's assume that you have at least one inch of finish material applied to the bottom of the beam.  Be very careful as your building inspector will be unforgiving and you can not afford to install this beam twice.

Either way, the ends of the beam should be supported by two or three trimmers - depending on your use of Southern Pine (only two on each end) or Hem-Fir (you will need three on each end of the beam).

The size for these two beams (LVL versus steel) is based upon the following variables:
Tributary floor area: 214 square feet.
40 psf live load
10 psf dead load
Maximum Moment: 25,000 lbs-feet

I would recommend that you call your local Home Depot and confirm the cost of three 1-3/4" x 14" LVL 2.0E

Let me know if I am not understanding something in your description of the existing conditions.

Happy Holidays

Richard Burton, AIA
Registered Architect

I am not a structural engineer and will not assume any liability for the use of the information provided above.  Either the building owner or contractor shall be responsible for any structural damages regardless of any unforeseen conditions, errors or omissions.


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Richard Burton AIA


A combined total of 25 years experience with construction, architecture, and building code enforcement. Ask me about residential and commercial design. Ask me about design aesthetics, structural methods, and building something that will withstand severe weather conditions. Ask me my opinion about YOUR design ideas and I will tell you the merits of good design and challenge your thinking about practical issues. Ask me how to best find and work with your local architect and approach general contractors to get the most value for the least amount of headaches. You can ask me about improving your energy efficiency and things that are both green and practical. But don't ask me about solar panels and wind turbines unless you are currently paying your utility company 35 cents per Kilowatt. Otherwise the math does not justify the initial cost and return on investment. Ask me any building code question and how to get a building permit from the most difficult enforcement agencies.


Here in the midwest, we design and build "green" in ways that make sense. My construction methods prioritize weather resistance, ease of maintenance and durability. While a graduate student in San Diego, I taught drafting and history of architecture. After working ten years for other architecture firms, I have started my firm Arrow Architecture in 2008. More than half of my work involves commercial office buildings. But my portfolio of work also includes custom homes, residential additions, home remodels, and second story additions.

President-Elect of American Institute of Architects - Lincoln, NE

B.S. Architecture - (Interior Design) University of Nebraska Lincoln 1997 Master of Architecture - (Urban Design and Professional Practice) NewSchool of Architecture - San Diego 2004 Graduated Summa Cum Laude ICC Certified Building Plans Examiner

Awards and Honors
AIA Henry Adams Medal and Certificate

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