Widen a door to an 8′ open walk through
shanana
| Posted in Construction Techniques on
NEed to know what size to make a header over an existing door that I’m widening to open a wall to an bar looking into the kitchen. A header will be needed to support 2nd floor, load bearing wall, want to open the space up and not lose the lower kitchen cabinets, so the wall will be shortened down to bar height, crippler studs to support the header etc etc…
just wondering what the correct size header to put in 2×8,2x 10, 2×12 with plywood sandwich????
Replies
A 4x12 d.f. header should do it . Maybe double trimmers.
How tall is the ceiling?
No one can give you the right answer here without knowing what's above it and what it's holding. You said it's supporting a second floor bearing wall. What does that mean????
What size joists?
What is the span?
What size ceiling joists if any are sitting on that wall.
What is the span of the ceiling joists?
Is there any structural beams or posts that are sitting on that wall above supporting the roof?
It's not just a simple 8' opening question. So for anyone to give you answer just on your 8' opening with a supporting a second floor load bearing wall is ridiculous.
Call an Architect or Engineer to be safe.
Thanks! I went to HD and found a code book! It looks like a 2x12 d.f header with double jack studs will be the answer, but will probably call an architect/engineer this week to verify.
Back with more info....I'd like to stay within the 2x4 wall, so LVL or the filtch plate make an interesting approach....
Edited 10/31/2005 2:11 am ET by shanana
I did somthing similar to what you're talking about. I used 4 2x12's and double trimmers. My clear spans were kinda long, I cant remember exactly but I think either the code book called for four or I was just being anal.
I would contact an engineer or at least submit plans to the city for review.
If you have to stay within the confines of a 2x4 wall, its time to look at steel beams.
Edited 10/30/2005 2:41 pm ET by MSA1
"If you have to stay within the confines of a 2x4 wall, its time to look at steel beams."Not necessarily. Depending on his situation if he has a 2x4 wall, he can use a 3-1/2" x 11-7/8" up to 18" microlam. If they don't work then he can use 2x material with a 1/2" flitch plate in between.Sometimes the height is a factor which he can cut out the top plate or both top plates. This is not a hard project at all. According to him he can get away with 2-2x12's so far until he calls an Architect of Engineer.Joe Carola
If you cut the top plates you denigrate the integrity of the wall versus perpendicular forces. It may resist shear but it will have scissor points imparting flex to the wall. It may not fail in a sudden load event (hurricane force winds) but over time it will move out of plane. You would be able to push against it and make it wiggle and wave.
A continuous top plate is pointless if you chop it out to fit your header. Why do we lap the cuts on double plates? By chopping out the plate and shoving the header up you're creating two scissor points for the the wall to move under load, including wind stresses.
"If you cut the top plates you denigrate the integrity of the wall versus perpendicular forces. It may resist shear but it will have scissor points imparting flex to the wall. It may not fail in a sudden load event (hurricane force winds) but over time it will move out of plane. You would be able to push against it and make it wiggle and wave."I've done this many, many, times before. If the top of the microlam is flush to the top plates and the joists are nailed on top of it, how can you push the wall and where is the wall going to go?All the jobs I've done that way are still standing with no cracks.What happens to all your walls when the duct guy cuts the plates right out of the way? They do that every day around here and we have no problems.I'm not saying that we do this every day with headers but there are times when we have to on new work and old work because of a height problem. On new work we can just put a flush header in and hang the joists. Sometimes we can't put a flush header in because it's a rafter wall (yes,rafter wall) and we eliminate the top plates in that section. There's been additions and houses that I've framed where we didn't even use top plates just microlams."A continuous top plate is pointless if you chop it out to fit your header. Why do we lap the cuts on double plates? By chopping out the plate and shoving the header up you're creating two scissor points for the the wall to move under load, including wind stresses."Maybe from where your from you can't frame that way but here we can and have no problems. Where is the wall or header going to move with the joists nailed on top of them holding them in place. Are you saying that the joist don't hold anything in place?Joe Carola
Edited 10/30/2005 7:50 pm ET by Framer
Yeah a microlam would also work, but "up to 18"? This is a pass through. In my limited experience w/both steel and "lams" Steel would be cheaper and possibly easier (lighter) to install.
We have not been given the clearest view of this picture. Unless I missed a post all I know is were taking out a wall that bears the weight of the second floor and replacing it w/ a 8' hole. I didnt read anything about clear spans, whats below the wall as far as support or what else is up stairs.
I agree its not a hard project, but ya cant be sure without seeing it.
Never used a "flitch plate" before. Sounds like a good way to go here. Arent they made of steel?
A flitch beam is built by sandwiching a steel plate - say (9" x 1/2" x 9') between 2x10s. The assembly is through bolted with carriage bolts with nuts and washers. You order the steel with the holes predrilled. Obviously, this is just an example of a typical size. It's easy to work with because you can attach it and attach to it just like a wood header. Generally, they are stronger (longer span possible) than an LVL beam of the same size.
Personally, I think this guy's application would call for a LVL beam assuming a 2x4 wall. I guess LVLs are pretty similar to microlams.
Edited 10/30/2005 10:04 pm ET by Matt
Flitch plates are steel and are used all the time around here and work great. There's a company called "Better Header" that makes them for you any size and length you want. I've use them a couple times already. The bolts are flush. They also make I-beams that are already packed out for you. They make them for exterior applications also.http://www.betterheader.com/kilndried.aspJoe Carola
dittotyke
Just another day in paradise
What Framer said, but I'll add that a double 2x8 is not going to be adequate for just about any load bearing 8' wide opening. Probably not a double 2x10 either. It also depends on what species of wood you are using. BTW - you also need to figure out how many jack studs you need on each end of the header and probably need solid blocking below them. A code book for whatever state/providence/etc you live in will get you headed in the right direction and will probably have a header span table and something about jack studs also.
BTW- welcome to BT! I can see now, it will be a bumpy ride :-)
Since you're tearing the wall open why chinz? 2x12 headers, tripled. I've always felt that ply in between gives the spikes room to shift under load so I nail up the dimensional lumber tight then pack with ply. Double jacks and I'd go with double kings. If the load above is extreme then perhaps triples. Nail together with two spikes every foot rather than 16". To put the header tight to the top plate and cripple down or the reverse is an endless arguement. Watch your mechanicals. If wiring is run tight to the switch by the door which you're widening this may complicate things. Hope there isn't a bathroom above then you have plumbing issues! Nothing that creativity, common sense and sweat can't overcome. If you think you need a stud, put it in, they rarely break the budget versus a cracked mudjob and repaint!
What's below? The widened opening may require additional load columns below since you spreading the point of load out. If it's a load-bearing wall then it should be supported to foundation but by spreading the two points of load they may not line up with the lower structure. This may not be a big deal, adding double studs directly beneath the jacks above ("as above, so below") but then it could hump your floor in the passway or worse.
"Since you're tearing the wall open why chinz? 2x12 headers, tripled. I've always felt that ply in between gives the spikes room to shift under load so I nail up the dimensional lumber tight then pack with ply."What if the wall is 2x4?Joe Carola
If the wall is 2x4 and carrying the load then of course I would just build to fit. If I have the room, I add wood, so to speak. If the 2x4 wall is bearing the load then fine, so long as the bearing points below line up...