Replies

1. 
   DanH | Feb 18, 2005 07:36pm | #1

   If this is the top floor, and the attic is framed with trusses, then absent any wierdities none of the interior walls are load-bearing.

   If the roof is conventional stick framing then usually the central wall, under the peak, is nominally load-bearing, but none of the others are.

   If the roof is not "simple" (eg, has dormers or runs in two directions and meets in a valley) then there may be load-bearing walls in the vicinity of these features.

   If there is a floor above this floor then things get trickier.

2. 
   BossHog | Feb 18, 2005 07:41pm | #2

   Look in the crawlspace or basement UNDER the wall. If it's a bearing wall, there should be a beam or some other form of support beneath it.

   Also - How old is the house? Is the roof stick framed or does it have trusses?

   Most houses with roof trusses don't have interior bearing walls. Stick framed houses often have a center bearing wall. But walls perpendicular to the outside walls generally aren't load bearing.

   If you have any doubt at all, get someone to come out and look at it.

   When I make a joke, nobody gets injured...when Congress makes a joke, it's the law. [Will Rogers]
3. 
   highfigh | Feb 18, 2005 07:41pm | #3

   Walls don't hang from above in order to distribute their loads. They're supported underneath. Go to the basement and see where the beam(s) are. Figure out which walls are supported by this and go up from there.

   Is this a one story or more? Can you give a bit more detail about the way the house was built?

   "I cut this piece four times and it's still too short."

   
   

   ---

   Edited 2/18/2005 11:43 am ET by highfigh

1. FHB Editor
   JFink | Feb 18, 2005 10:34pm | #4

   There are several signs that you might be dealing with a load bearing wall:

   - as said above, look in basement or attic to see if the joist ends are resting on the top plate of the wall

   - look at the roof of the house, floor joists generally fun perpendicular to the ridge on gable roofs (ie, ranch houses, capes, colonials). watch out for hip roofs though, because they can have joists running in either direction.

   - an electronic studfinder is also a good way to find which way the joists are running (as long as the ceiling wasn't furred with perpindicular strips of course).

   -if all else fails, call an expert to take a look or simply go to the town hall and get a copy of your house plans (town hall? or maybe building department, not sure?)

    Justin Fink

   FHB Editorial

2. 
   1525 | Feb 19, 2005 05:32am | #7

   I really appreciate all of the responses in reference my question. The only downside to the responses is that now I know I shouldn't be messing with the wall.  As far as more info, the house is single story, built in 1978, and here is my real problem, I want to say "no trusses," but I might be lying. It certainly doesn't look like it and in fact, it looks like the last resident may have thought a little more support was needed due to there being 2x's in places I have never seen 2x's before. i.e., some, "I dont know if this will help, but surely it couldn't hurt" afterthoughts going on in my attic. 

1. 
   FastEddie1 | Feb 22, 2005 10:48pm | #9

   Some of the oddly placed 2x4's could have been temporary supports or braces during construction. 

   If the roof is trusses, there's an almost certain chance that the joints will be fastened with metal nail plates. 

   now I know I shouldn't be messing with the wall.  Not true.  As long as you do a good job of evaluating the construction, taking out an interior wall and going through all the sheetrock and finish work would be a good job to do yourself.  Just be sure you don't overlook something.

   Any chances yoiu could post a picture of your attic, and m,aybe the wall you want to remove?

    I'm sorry, I thought you wanted it done the right way.

1. 
   BillHartmann | Feb 23, 2005 07:14pm | #11

   "If the roof is trusses, there's an almost certain chance that the joints will be fastened with metal nail plates."In 78 where there a lot of site built trusses that would have used plywood plates?

2. 
   highfigh | Feb 23, 2005 03:48pm | #10

   You didn't say what the desired opening size is for the wall. Are the 2"x4"s in teh attic attached diagonally from the joists to the rafters, at regular intervals or on every one? These would be trusses. If the wall in question is on the top floor of the house, its load will come from above- ceiling joists, drywall/plaster and insulation pretty much sums it up, unless there's storage above this area. The roof load is supported by the outside walls unless the roof is irregular and has obvious interior support members. If the attic is not directly above this ceiling, the new beam will need more height in cross section. in 2001, I removed part of a wall in the upper floor of my house. Hip roof, built in 1946, rock lathe/plaster and it's in line with the first floor load bearing wall. After talking to a couple of friends who are either architects in firms with structural engineers(these guys are not hacks) and the local inspector, it was decided that, to carry the load, a doubled 2"x6" LVL with 1/8" steel plate in the middle will work. I through bolted this together and made sure it was crowned correctly. This spans about 13'-6" and when I was in the attic after installing it, I jumped on the decking over the new beam and it didn't even bounce(I had someone with a tape measure underneath checking this). When I removed the wall, I left the top plate attached and removed the studs. Four years later, there are absolutely no cracks in the walls, ceiling or corners and I have been in the attic quite a bit since then. As long as the new beam will carry the load, the next thing to get right is the means to transmit the load successfully to the foundation. It can be done.
   "I cut this piece four times and it's still too short."

4. 
   JohnSprung | Feb 18, 2005 10:43pm | #5

   Gee, it's been a while since we've seen this question.  It used to come up often enough that I wrote a FAQ about it.  Here it is:

    

   How to identify bearing walls:

   When somebody asks how to identify load bearing walls, it's usually
   because they're thinking of removing a wall or cutting a big hole in
   one.  That can be serious business, not something that can be designed
   adequately by using a FAQ from the internet.  The following discussion
   may be useful for the preliminary speculation phase of such a project,
   but don't rely on it for anything more.

   Removing a load bearing wall is not impossible, but it is more
   expensive.  Often much more expensive.  It will require some sort of
   substitute support for the weight it carried, usually a beam.  Often
   this beam will have to be large enough that it extends downward from
   the ceiling fairly far.  On a top floor, you may be able to hide it in
   the attic, and hang the ceiling joists from the side of it, or even
   from the bottom.  But often the ugly beam sticking down, which always
   looks like you took out a wall, defeats the architectural purpose of
   removing the wall in the first place.

   You'll also have to provide adequate support under the ends of the
   beam, because the load that was formerly distributed along the length
   of the wall is now concentrated there.  This load has to be supported
   all the way down to the ground.

   The official code definition of a bearing wall is any wall that
   supports 100 pounds or more per foot of length, and any masonry wall
   that supports any additional masonry above its ceiling level.  That's
   not particularly practical or helpful, since there's no instrument to
   measure the weight on the top plate of a wall.

   In general, you have to look at what the wall supports, and what
   supports it.  Walls that are parallel to the joists above are usually
   but not always non-bearing.  On my top floor, I have a wall parallel
   to the joists that supports the rafter tails of a decorative roof
   section.  On the top floor, always look in the attic to see if the
   wall in question carries any roof load.  Then look to see if it
   supports ceiling joists.  If the joist tails rest on a wall, it's
   almost always bearing.  I have one exception to that upstairs, where
   the ceiling joist tails rest on a non-bearing 2x3 wall that was the
   partition between two closets, each 10 feet by 27 inches.  On each
   side, the real bearing walls are only 27 inches from this partition
   wall.  They form the sides of the stairwell.

   Taking that idea a bit farther, you may want to analyse the whole
   house, figuring out from the top down how the weight of all the
   materials and contents are supported all the way down to the ground.
   That's the way engineers design structures, from the top down.  They
   have to do it that way, because they can't design any part of the
   structure until they know the weight of the stuff it supports.

   In the past, building codes used to allow 2x3's for non-bearing walls.
   Now 2x4's are the minimum for all walls.  I know that was changed
   prior to 1971, but I'm not sure how far prior.  It's possible that
   you'll find a load bearing 2x3 wall if bootleg remodeling removed a
   nearby bearing wall.

   For ground floor walls, look in the crawl space or basement.  A
   bearing wall perpendicular to the joists should be no more than one
   joist depth away from some sort of support -- a girder or cripple
   wall.  That's a code requirement for all walls, not just on the ground
   floor.  So, if your joists are 2x10's (actually 9 1/4"), and a wall is
   10 inches away from the nearest support, it's probably not supposed to
   be bearing.  The exceptions are if the original design was done by an
   engineer, or the building is old enough to pre-date that code.

   In old houses, bearing walls parallel to the joists below may have no
   extra support.  In newer construction, they'll usually have a joist or
   two under them.  The best practice is two joists with space between
   them for utilities to run into the wall without hacking up the
   structure.  As always, beware of bootleg jobs that may have
   transferred loads to walls that legally shouldn't carry them.

   The tough part comes when you have three or more stories, and you want
   to work on the in-between floors.  First, you should start from the
   attic and work down, because any bearing wall up there has to be
   supported by bearing walls all the way down.  Then look in the crawl
   or basement, and work your way up.  As with the crawl space, the max
   is one joist depth away from floor to floor, unless it's an engineered
   design or an old building.  Next you may need to do some exploratory
   demolition of the ceiling to see what's on top of the wall in
   question.  Again you're looking for joist tails, this time floor joist
   tails.

   Finally, even if a wall appears to be non-bearing, if it's
   perpendicular to the joists above, you have to determine the size of
   those joists and the new distance they'll span if the wall is removed.
   If there are no walls or roof load supported by those joists, you can
   look in the span tables to see if the result will pass code.  If they
   support other parts of the structure, engineering calculations are
   necessary.

   Most people at this point should hire a structural engineer.  If you
   don't want to hire an engineer, get some engineering books from the
   library.  Unless you have a very strong technical and math background,
   that kind of light reading will probably convince you to pay somebody
   who already knows this stuff.  Even if you have the ability to learn
   enough for a simple job, an experienced engineer's second opinion may
   well provide you with a more cost-effective solution and save you more
   than the engineer's fee.

   Most jurisdictions will require a licensed engineer's wet stamp on plans
   before they issue a permit for structural work.  So even if you could
   learn enough to do it yourself, your local building department may not
   accept it because they don't have the resources to check your work.

   What you may be able to do for yourself is measure and draw.  If you
   can make good accurate measurements and drawings of what you have and
   how you want to change it, you may find an engineer who will do your
   job from your drawings, without the expense of a site visit.  Some will
   even do simple jobs via fax.

   A general contractor or rough carpenter might also be able to give you
   an expert opinion on whether a wall is bearing or not.  Please don't ask
   for a "free estimate" if you don't intend to hire someone for the job.
   The fair thing to do is pay them their hourly rate.  That might be about
   half what an engineer would charge for a site visit.

   Also, non-bearing is merely a legal term used in codes.  It doesn't
   mean that the wall in question has no structural role.  Gravity
   doesn't care whether we call a wall bearing or not.  After it's gone,
   the floor above may be less solid feeling, even though it still passes
   code.

   (Bearing Wall FAQ revised March 12, 2003)

    

   -- J.S.

    

1. 
   decornut | Feb 19, 2005 04:40am | #6

   I question your statement that all walls must be 2 X 4 minimum.  The 2000 IRC states (R602.5) "Interior nonbearing walls shall be permitted to be constructed with 2 X 3's"  And 24 inches O.C., no less !!

1. 
   JohnSprung | Feb 22, 2005 09:00pm | #8

   Thanks, I'll update the FAQ.

    

   -- J.S.