I have a living room that is 16×24 with a 17ft ceiling. I would like to add a Master BR above it. Can I simply remove enough sheetrock to put joist headers and stringers in place and hang my joists for the new floor? I know that I can get the lumber/trusses to make the 16ft span, but is it OK to hang them in this way with no wall/girder support under the ends?
Since this is a renovation I am having trouble getting info from the normal sources
Edited 1/15/2004 1:20:35 PM ET by chico
Replies
What you are calling joist headers and stringers is what I would call a ledger. If it is possible to adequately fasten this to the walls, it will support the floor with no problem. Some of this depends on how the walls are constructed. If there is a wood frame, it is relatively easy. If it is masonry, I would consult with my mason or someone experienced with these materials, which can vary quite a bit.
The walls are 2x6 wood exterior construction on 2 walls and 2x10 on two interior walls. My plan is to score and peel back the sheetrock to neatly fit the "ledger" around the outside of the room. I am planning in securing the ledger with some type of lag screw. Then I am going to use standard joist hangers to run the span. There is one complication to the plan: for achitectural reasons I would like to run 1/4 of the room one direction (16 foot span) and the other 3/4 running the other direction with the "inside" end hanging off of a tripled up 16 foot span of 2x10's. With the additional info, any thoughts on the whole plan?
Thanks!
As I understand it you will be having one-half of an 18x16 foot section supported by a triple 2x10 spanning 16 ft. This is not enough. If you want to span this distance you must do the calculations (or have someone else do them) to determine the size of the beam. A properly sized piece of steel would work well. In any event you will need to cut out a pocket under the ends of this beam for a column to support it down to the floor at the very least. What architectural reasons do you have for this complication?
I have several thoughts.
First, 2X10's won't span 16'.
Second, a triple 2X10 won't carry an 18' floor tie-in, as SCHELLINGM already pointed out.
Third - What's under those walls that you're planning on hanging the joists on? Are they bearing walls? If not, your whole plan needs re-thought.
Fourth - You said: "The walls are 2x6 wood exterior construction on 2 walls and 2x10 on two interior walls." Having 2X10 interior walls doesn't sound right. Do you mean 2X10 floor joists?
I'd give up chocolate, but I'm no quitter.
Boss,
The interior 2 walls are capped with 2x10 floor joist so that is what I would be putting my ledger to on those 2 walls. I can actually go to a 2x12 pretty easily if necessary. Regarding what is under these walls: the 2 exterior walls are concrete foundation, the 2 interiors are straight down to lolley columns in the basement. I am going to work up and post a diagram as I think that would be the easiest way to convey what I am trying to do. Check back later on that.
Thanks"I can do anything, just tell me how" - unknown
Sounds like a good situation for a structural engineer. Your ledger-to-wall connections and your lumber spans need engineering.
I have attached a quick drawing of what I am proposing. I can work with 2x10's or 2x12's."I can do anything, just tell me how" - unknown
It doesn't look to me from your drawing like the interior walls go down to columns. Looks more like there's nothing underneath them.
BTW - Saving a drawing as a .JPG insead of .BMP makes them about 1/10th the size.
With some modifications, I think what you want to do can be done. But you need to support what you're doing correctly, and get a beam that will actually work.
I really think you need someone to come out and look at the thing. Maybe not an engineer, but someone familiar with structural issues.Dinner is ready when the smoke alarm goes off.
I agree with Boss, it doesn't look like your interior walls are load bearing.
You can make them so by constructing walls or placing properly-sized posts and beams directly under them in the basement. (If you put in steel jack-posts to support the beams in the basement, you must put minimum 3x¾"-thick plywood plates 12"x12" under each post to avoid cracking the floor, assuming there are several of them. If not, see below. Once that's done, you don't have that much of a big deal except for your 'change of direction'. You can save yourself a lot of grief and time by getting an engineer to spec a steel beam for that span. Open up the living room walls and build columns down to solid support. The floor of the LR is not sufficient; you must go straight down to footings, with no bridging.
It looks like one of the end columns to support that steel beam will need to land somewhere on the floor slab in the basement. For this, because it will be carrying one half of the whole load of your second floor, you must cut open the basement slab about 3x3 feet, dig out the gravel and fill, and pour a point-load footing at least 24" square by 12" thick. Then you can pour a patch to the slab on top of that. This will prevent the column from cracking the slab and sinking into the gravel and fill underneath.
Hope you don't run into too many pipes under that basement floor, too, LOL!
Dinosaur
'Y-a-tu de la justice dans ce maudit monde?
If I'm understanding you correctly, you're more or less wanting to turn a tall ceiling framed room into two stories with the floor hung between the walls as in old style balloon framing. Using lags could be ok, but another method is to let-in a 2x (usually a 2x8 in my experience) into the studs below the level of the bottom of the new floor joists. The new joists can then be set right on the let-in ledger and side nailed into the studs. Many older homes were built like that.
Your existing walls may already have the needed fire blocking, or you may need to add fire blocking.
Any jackass can kick down a barn, but it takes a carpenter to build one.
You have the idea, that is exactly what I would like to do as far as the room conversion. Thanks for the idea about letting in the 2x's. One challenge with that is the extra rocking and mudding for the "let-in". If possible I would like to just cut the rock for the ledger and make it as clean as possible but I will consider all options. This will be a pretty disruptive project for the family so I would like to minimize the extra work. Bottom line is if I don't go the "let-in" route do you think lagging the 2x ledger into the 2x6 framing is sufficient? (Note in the picture that on the wall between the proposed 3rd floor steps and the current master closet I will be mating the ledger into a current 2x10, which I am sure will be fine, it's the 2x6's I am questioning)
Attached is the revised joist layout, now both ends of the center beam, likely a 2x12, carry to solid support in the basement, one in a pocket in the outer wall to the outer concrete wall below and the inner end to a lolley in the basement. Also the joists now only run 12 ft, thus strengthening/stiffening the floor.
How about the proposed steps to the 3rd floor? Don't think those should be a concern, anything I am missing? The inner wall of the steps would then be carrying the attic floor joists. The span to the front roof rafter would then be about 14ft. Joists are 2x10's up there so that should be sufficient to support a floor considering the relatively short spans.
All input welcome and appreciated.
-chico"I can do anything, just tell me how" - unknown
"...if I don't go the "let-in" route do you think lagging the 2x ledger into the 2x6 framing is sufficient?"
In general, I think lag bolts are a bad idea. Using joist hangers on the existing band board or notching the joists in are much better approaches.Happiness is like a cloud - If you stare at it long enough it evaporates. [Sarah McLachlan]