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Hello all-
Haven’t been here for a while, have a quick span question. I have a guy who wants me to remove the header over a door opening to make it a full height door. (It’s currently ~76″). I’m dealing with some pretty creative home-grown Interior Alaska engineering here. The 2×6 wall through which the door passes supports a triple 2X6 beam (parallel- that is, the wall runs along under the entire length of the beam). I’m planning on just removing the header, and doubling up 2x6s to make columns on either side of the door opening to support the tripled beam- ie the tripled beam would have to span 3′ over the door. The top plate of the wall would remain under the beam, and the result would be an almost perfect RO. I can’t see any problem with this, but I thought I should throw it out there in case I’m missing something…
Thanks, Olav
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Mr. Ormseth,
Sounds like you're simply raising a header into a floor or wall above. 3-2x6 headers are pretty stout... what's the load above? You can probably carry a floor and a roof on that header given that it's only a 3' span AND that there are not any concentrated loads (point loads) above. More loading details would help for some absolute responses.
BTW, I was named after my long deceased norwegian uncle who was named after the long deceased Crown Prince Olav of Norway. What's your connection?
The Machine, aka Olav
*Machine-I realized that my description wasn't that accurate. The triple 2x6 beam is actually about 20 feet long, with a 2x6 wall running along underneath it for the entire length. The door opening is about 1/3 of the way down the wall, and has a 2x6 header above it. The beam supports only a fairly small roof (sort of a shed style roof coming out of the main part of the house- around here there are lots of places that were built in stages, basically made up of 10 or more "additions" to the original structure- makes for interesting work). Because the beam is only about 82" high, the header makes the door opening about 76", and instead of cutting down a stock door or making a custom one, I figured the cheap and easy solution was to simply remove the header. I think I get what your saying- that functionally, the section of beam above the door opening becomes a header, and a triple 2x6 header is plenty stout for the 3' span...Re: the name- my parents are Norwegian... I'm glad to hear of another Olav out there, there aren't many of us...around here there are a few Olafs (Germans) but it's not quite the same. When I was a kid I got a kick out of telling people I was named after the king of Norway...-Olav
*I bought a simplified engineering book a couple weeks ago, and this reads like a homework problem for it. So, with the disclaimer that I might have my homework all wrong, here goes:It depends a lot on where the roof structure attaches to the triple 2x6 beam. The worst case would be to have some of the load centered over the door. The maximum bending moment M = S x Fb, where S is the section modulus of the beam, and Fb is the maximum allowed extreme fiber bending stress for the material. Assuming #2 Doug fir, M = 7.563 In^3 x 810 Lbs/In^2 = 6162 In-Lb. = 510.5 Ft-Lb., for one 2x6.Section modulus is linear with respect to width, so for your beam, the answer is 3 x 510.5 Ft-Lb = 1531.5 Ft-Lb.For a centered point load of weight W, and a span of length L, M = WL/4. We know M and L, so solve for W = 4M/L = (4 x 1531 Ft-Lb)/(3 Ft) = 2042 Lbs. Being really careful, we might subtract 18 pounds for the weight of three feet of triple 2x6, leaving 2024 Lbs. So, it looks like you're good for about a ton in the middle of your doorway. BTW, if it were a uniformly distributed load, the 4 would be an 8, and you'd be OK for two tons. In addition to the roof, you also have to consider the ceilings it's supporting.These calculations are for a simple header. You actually have a beam with restrained ends, because it's much longer than the rough opening. That makes things better, but I haven't got that far in the book yet. ;-)But, of course, I only bought the book a couple weeks ago, and I could be completely wrong. -- J.S.
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Hello all-
Haven't been here for a while, have a quick span question. I have a guy who wants me to remove the header over a door opening to make it a full height door. (It's currently ~76"). I'm dealing with some pretty creative home-grown Interior Alaska engineering here. The 2x6 wall through which the door passes supports a triple 2X6 beam (parallel- that is, the wall runs along under the entire length of the beam). I'm planning on just removing the header, and doubling up 2x6s to make columns on either side of the door opening to support the tripled beam- ie the tripled beam would have to span 3' over the door. The top plate of the wall would remain under the beam, and the result would be an almost perfect RO. I can't see any problem with this, but I thought I should throw it out there in case I'm missing something...
Thanks, Olav