Load-bearing Walls- How do you identify?

[BigguyZ]

OK, I've posted a couple of threads regarding a built-in I'm planning to build. The plan is to build a cabinet with drawers and shelves from my bedroom into a closet.

However, I am slighlty concerned that the wall is load-bearing. The height of the bedroom and the height of the closet are not the same. The closet ceiling is about a foot or so shorter than the bedroom closet. Last night I opened up the wall on the closet side to see where the studs are and what I have to work with. I plan in builing the unit between two of the studs and cutting through two others in the middle. See the attached diagram for reference. Looking at the wall, it definitely goes up further than the ceiling of the closet. How much further I'm not sure. But I'm wondering is it's load bearing, and if it is, would the support of the additional framing I'm planning be enough to brace that wall?

Thanks!

[LarryG]

There's no sure-fire way to know, just from looking at a wall, whether it is or is not load-bearing. There are some design and framing conventions that will often provide strong clues, or even the answer in a high percentage of cases; but I've seen many a case in which the clues were misleading. In order to know for sure, you have to examine the framing members that cross over the top of the wall ... figure out which way they're oriented, and where their ends are. In attics, unfinished basements, and around stairways, this is usually pretty easy. With an intermediate floor, with finishes on both top and bottom of the framing, not always so easy.

If it IS load-bearing, what you have drawn there isn't adequate. You'll need a header across the top of the opening, to support the two cut studs and transfer the load they're carrying to the jambs. The size of the header will depend on the load, and the span. In standard light residential construction, for standard-sized man door(s) and window openings, (2) 2x12 with a 1/2" plywood flitch plate in between is generally adequate for all but the most unusual of situations. In many cases, including probably this one, it'll be overkill but if you only have to build one, the work is the same as for a smaller header and the material cost is only slightly more. The header should bear on a minimum of two "trimmer" studs at each end, with a full-height "king" stud immediately adjacent, with all members nailed together.

On our projects, we never show anything less than a (2) 2x6 header with a 1/2" plywood flitch plate, even for a non-load bearing wall.

[pelligrini]

To see if it is load-bearing check to see if any ceiling joists bear on it. If the ends of the joists are above that wall it is load bearing. Like Larry said, it's still not easy to find out for sure.

You'd be better off treating it as a window opening, using trimmer studs and a bigger header.

Framing Diagram

[BigguyZ]

Well there's no way for me to access the crawl space where the joists meet with the walls.

The total span between the left and right most stud is 43". I'm thinking that the wall extends up to the attic/ crawl space, as there's some cellulose insulation at the top of the wall, held in place by some cardboard. Here's a pic of the wall.

[LarryG]

If you can't access the area above to figure out what's going on, then as pelligrini says the only safe course is to treat it as you would an opening in a bearing wall. If it's carrying only a roof load, for a 43" span you could probably safely reduce the depth of the header; then again, for that size span a single eight-foot 2x12 is enough to build your header and that won't cost all THAT much more than a smaller stick. Always safer to err on the side of overkill when you're talking about something that may be keeping your house from collapsing onto your head ...

[BigguyZ]

Looking at Pelligrini's PDF, I see that they use 2 2x4s as a header. Would that suffice? I could put a 2x4 trimmer stud next to the outter "King Studs" and have those hold up the doubled 2x4 header. Then install a sill on the bottom portion.

[LarryG]

Read the last sentence of my previous post again.

Also, the PDF does NOT show two 2x4s for the headers. It says "DOUBLE 2 x HEADER ..." with the depth dimension not given. This is standard notational practice, and means that while the header is constructed of lumber that is nominally 2" thick (1-1/2" actual), the depth of the header (width of the lumber) has to be sized to carry the load. In some cases ... yes, two 2x4s would be okay. (As I mentioned before, we never detail anything less than 2x6s, even for a non-bearing wall.)

For a roof load only, and a span of this size, two 2x6s or two 2x8s might be more appropriate. The point is that you don't know what you need. Hence the recommendation for 2x12s.

[pelligrini]

I wouldn't do anything less than two 2x6's either. That's what most all our engineers call out for openings up to 48" for non-load bearing locations. Since you don't know for certain I would think 2x8s would be minimum.

When I do details I call out 2x and not give the depth, I leave that liability up to the engineer.

[BigguyZ]

Well, the larger the header the less space I'll have for the built-in. But, I guess you're all right about not wanting to take chances. 12" seems like it'd be overkill for such a small span, but I think I can live with 8". Do you think I can skate by with that, or should I just bite the bullet and go with 10 or 12"??

At this rate, I'l loosing so much I might as well just build 3 separate units between the studs...

[pelligrini]

The header could go flush up against the top plate. How tall is the clg and how tall do you wan the built-in?

The bottom of a 2x12 (11.25" deep) header, flush against a double-top plate (2x1.5") would be about 13-3/4" below the bottom face of a 1/2" sheetrock ceiling.

[BigguyZ]

Well, as I noted above, the height of the ceiling in the closet is lower than the height of the bedroom ceiling. Also, my walls are plaster, not drywall, and I'm no expert in patching either. So, I'd like to avoid cutting into the bedroom side as much as possible. I'll attach a picture of what I've done so far. I've removed the plaster and lath from the area I want to have the built-in on the closet side. So right now, the wall from the bedroom looks untouched. What I plan to do is to install any bracing (headers, etc) from the closet side prior to cutting into the bedroom side of the wall. Then, I'll cut int the bedroom wall only where the new opening with the framing is. Therefore, that'll be that much less I'll have to patch up later.

[JimD]

You can determine if the wall is definitely not load bearing without access to the attic but it will take some time with a stud sensor on the ceiling. All you need to do is find a ceiling joist with the stud sensor and determine which way it runs (i.e. find it again or follow it with the sensor). If it runs parallel to the wall, it is definitely not load bearing. If it is perpindicular to the direction of the ceiling joists, it might be load bearing. If the wall is close to an exterior wall it is probably not load bearing (the exterior wall would be). To be safe, you should check ceiling joists on both side of the wall (sometimes they change direction at a wall).

If your ceiling is lath and plaster, I think you can still do it but the stud sensor would be the limitation.

If you do not have access to the attic, that is another thing you may want to consider fixing. I have never owned a home without attic access and if I did, I would add access. It is handy for storage but also if you ever need to run a phone line or an electrical line or anything.

Jim