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vanish

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Hello, everyone,

Here is my situation.

I am creating a pantry 4 feet deep (2 feet in kitchen and 2 feet in form of a bump-out into the adjoining laundry room). There are no plumbing issues or electrical issues involved.

I want to create an 5 to 6 foot opening thru what was once the outside wall of my house (a laundry room addition made it an inside wall) so I am assuming it is load-bearing. Pantry will end up 4 feet deep and 5 to 6 feet wide.

The wall is at the gable end of house and rafters run parallel to wall to be cut.

I do not want a header to extend down into opening.

Is it possible to "raise the header and provide proper support to this end of the house? And how? If header is "raised" what would you suggest for the size of header and what would be the suggested size of new the posts which would carry load for removed studs?

And, thanks for all the help I have gotten in the past from other peoples questions and the replies.

Daniel Holzman

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Civil Engineer
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Step 1: Verify that the wall is load bearing by examining the framing above the wall to see if load is in fact being transferred through the wall.

Step 2: If the wall is load bearing, determine the pounds per foot that the wall is carrying. This depends on the load above the wall, which is usually determined by code (varies if the space is living room, storage, or attic).

Step 3: Determine based on the geometry of the space above how much vertical clearance you have.

Step 4: Design the hader based on loading and geometry determined in previous steps.

Step 5: Determine the required support based on what type of load bearing element is in place below the ends of the header. Typically a doubled 2x4 is used on each end, however current code requires a tripled 2x4 if the load is sufficiently large.

Step 6: Take the design to your local code enforcement official for approval.

Step 7: Temporarily support the ceiling above while you install the header.

Step 8: Remove temporary support, have a drink.

Augie Dog

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Cabinet maker
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The best (safest for anyone here) advise would be to consult an engineer.

But this is what I would do;

First, a simple gable end has little to no weight bearing on whatever header is placed in it. The rafters and the ceiling joists create a truss like effect and the weight from above is transfered to the walls with the rafters landing on them and usually a ceiling load where the joists are spliced together in the middle of the house somewhere. Very general description for a basic rectangle house with a straight and common gable roof.

That aside, when you cut the plates at the top of that old outside wall what you really are doing is losing some of the resistance to the outward thrust of the rafters. So when you place the new header up on top of those plates in the attic the concern I would have is how well it ties the two sections of plates together.

That could be accomplished several ways but one could be truss plates on the sides or another could be lags from below, through the bottom of the plates into the header.

The size of a header header is based on the load. For that there is way too much more info needed than you have provided but I think it's safe to say I would use a 4x8 or so in my house.

I hope the two ceilings plane in nicely for you. You may need some creative cheating to get a nice smooth transition there. All in all not too difficult for someone with a good mind for this type of thing.

I hope this helps

mrgins

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Since you say it's the gable end, and the joists run parallel, I'm sure that any weight applied to that area is wall material and not live load, and is also more or less self bracing because of the plywood sheathing. My concern is, as Augie mentioned, cutting the plates. If there is living space above, then the plywood floor sheathing and the band joist should take take of this problem, but check it out before cutting the top plates.

vanish

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OK. I get what you are saying. Bearing weight on wall is not that great. Roof rafters and ceiling joist make a truss arrangement. My cutting the header plate would remove integrity of truss triangle causing it to want to flatten.

So my plan is to set in adequate header (probably over-adequate) with gable end studs cut and reset on top of new header and old header plate FIRMLY attached (at ends where it will be cut out) to new header above.

Then I make the cuts.

I tend to overdo everything so I will probably lag bolt up thru, install plates where I can, tie everything together wherever i can. I am certain I can stop truss dynamics from wanting to collapse.

I think that was the key. My understanding of the nature of what I was cutting. The weight was not my biggest thing, it was the removal of the truss's integrity.

Got it.

Van

mrgins

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OK. I get what you are saying. Bearing weight on wall is not that great. Roof rafters and ceiling joist make a truss arrangement. My cutting the header plate would remove integrity of truss triangle causing it to want to flatten.

So my plan is to set in adequate header (probably over-adequate) with gable end studs cut and reset on top of new header and old header plate FIRMLY attached (at ends where it will be cut out) to new header above.

Then I make the cuts.

I tend to overdo everything so I will probably lag bolt up thru, install plates where I can, tie everything together wherever i can. I am certain I can stop truss dynamics from wanting to collapse.

I think that was the key. My understanding of the nature of what I was cutting. The weight was not my biggest thing, it was the removal of the truss's integrity.

Got it.

Van
Not quite. We're not concerned with weight coming from the top down, we're concerned with pressure from side to side. If you imagine a strong wind blowing into the center of the wall, then you cut the plate which is the lateral strength of the wall, that is the direction of the force that you're possibly weakening. But, as I said, the upstairs floor sheathing and rim joist should take care of that.

vanish

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Mr. Gins....

More detail to make certain that I have this tied up in my mind.

My house is sort of a walk-in basement lower level, Concrete block. Living area is upstairs with an attic over that.

The wall I want to cut thru is on living area floor and the header will be in the attic.

The cut-thru will be in a former exterior wall in the living area floor (which sits on a concrete foundation) and the header modification in the attic.

This is the new info... There is no floor sheathing in attic and it was built in a time/place where only the corners of the house have plywood sheathing. So, I only have the long side of rim joist along this wall.

So, with no floor sheathing, just the rim joist, your statement: "But, as I said, the upstairs floor sheathing and rim joist should take care of that" worries me. What more should I consider doing? I am not adverse to consulting an engineer, but I really like to understand what I am asking before I go ask a professional their opinion. I sort of think good DIYers have a hands-on understanding of issues.

Thanks for your help.

Van

Gary in WA

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Contact a S.E. as you only have ply at the corners and will be making two new corners that may require shear flow.
The laundry room addition roof direction was not mentioned..... You may have rafters bearing on the proposed opening...

Follow Daniels advice in post #2. Remember to add in-floor blocking to carry the post bearing down.

Here, in a seismic zone, would require straps or a drag strut to continue the shear loads and ply at the new corners, beam to post straps, beam to plate straps, possibly additional wedge anchors near the posts into concrete wall, etc.....

Gary

vanish
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