Need some ideas on supporting a 2×4 ceiling in the attic.
I’ve attached a crude drawing but the span across living room and dining room is about 30 feet. Where the living room meets the dining room a 2×4 intersects so that the ceiling joists for the dining room and living room are hung on this.
Looking for suggestions on how to stiffen this up, support it better. After doing a little bit of work up in the attic the drywall cracked at this joint. The intersection is 8 feet wide. Thanks for any ideas.
Replies
drop some hangers from the attic ridge
Mike Smith Rhode Island : Design / Build / Repair / Restore
Cut out the drywall so that the meeting/lapping of the ceiling joist are in the middle of the whole sheet of dry wall. My guess is that the drwallers did not stagger the joints or place them away from wood connections.
Any chance we could get a pic of the situation? I'm not clear on what's going on from your sketch.
Sounds like you've got a bunch of ceiling joists hanging on a 2X4 beam?
Do not argue with whomever is packing your parachute.
That's pretty much what it is, the ceiling joists are hanging off of this 2x4 'beam'. The drawing is the two rooms, the larger one is the living room, smaller is the dining room. It's open between the two rooms so the only support for the beam is the dining room walls.
The joists that cover both the dining room and the living room are joined together by this 2x4. Since the living room is larger it's not on centered or directly under the ridge.
Can you join two boards on edge to make one? I thought about laying a 2x8 on edge on top of this 2x4 and joining the two with metal brackets. Would that be stiff enough? Would glue help?
O.K., next question -
Are these rafters and ceiling joists, or trusses? That would make a lot of difference.
Either way, I'd say you need to do something.If you want your spouse to listen and pay strict attention to every word you say, talk in your sleep.
Rafters.
Yes, something needs to be done. I was surprised to see it myself but the house was built in the 50s.
My first inclination would be to say the beam needs to come out and be replaced. But I know that would be a pain in the neck.
Stacking another beam on top of it and connecting the 2 with straps might work. But it would still be difficult.
Maybe someone here will come up with a brilliant idea.My Wife asked me how long I was going to be gone on this business trip. I said, "the whole time."
drop some hangers from the attic ridgeMike Smith Rhode Island : Design / Build / Repair / Restore
How about building a "hogs trough" across the weak 2x4 beam. Use a 2x8 for the bottom nailed to the beam and the ceiling joist on each side. Follow this with 2x6 sides nailed to the flat 2x8 and then 2x4s up to the rafters. Every nail except the ones into the top of the beam and joist is in shear. If the 2x4 beam is built up, he may want to use lag screws through the bottom of the trough to the beam..
This works particularly well if the trough is sitting on two bearing walls. Can,t tell from the drawing what is on each end of the opening, but using joist hangers can be worked in where needed.
I have used this to stiffen open spans like that in houses built in the early fifties.
Dave
Mike, you say from the ridge but it's a good 3 or 4 feet off center, isn't that too much of an angle to hold it up?
max , you dog...
you could clear this up with a section drawing... but noooooooooo..
you give us a framing plan of the ceiling..
anyways.. I'M JUST GUESSING what you got.. you 've got a typical old ranch style with a mid-pitch roof and 2x4 ceiling joists.. the ceiling joists are keeping the walls from spreading..
the rafters push against the walls and bearing on the ridge.. they push against each other..when they built the ceiling it was ok ( inadequate... but hey )
now you go up there and put some weight on it and it sags a little.... the common fix is to jack the ceiling back to straight... put a line and block on it so you know when it's straight.. then go back up in the attic with a saw and a bunch of 1x6 ledger boards... alternate on each ceiling joist..... one from one side of the ridge to a joist .. the next from the other side of the ridge to a joist.. and so forth
... use a minimum of (3) 8d common nails at each end... this goes better if you have a nail gun..
when you're done .. blow a bunch of cellulose into the attic, close it up, and fogeddaboutit...
now ..if i guessed wrong... it won't fix it.. but i bet it does..
or you could have a competent builder look at it..
here's a ceiling that was dropped 3 inches....Mike Smith Rhode Island : Design / Build / Repair / Restore
Mike,
Thanks for the pics, I understand what you mean and it is very similar, except I assume those joists go wall to wall. So I have a couple of questions:
1) I assume it has to be at the ridge for the support. The rafters themselves wouldn't be enough to support it? In other words, to brace at the beam the bracing would have to be nailed about miday up the rafter, not the ridge.
2) if I do it at the ridge, since the beam will be a distance from the supporting braces, doesn't that reverse the roll of the beam and in effect the joists are now supporting the beam?
The weakness in my particular system is at the beam, shouldn't I be beafing it up?
Not trying to argue your point just want to make sure I understand what is happening and do it right the first time (this time).
max...... is this a true statement ?
<<<the only thing the ceiling is supporting is the plaster and the insulation in the attic ?>>>>
if that's a true statement.. then the loads are just not that great..
if you hang from the rafters.. they have to be strong enough so they won't deflect..
if you are in snow country.. you have to be more careful..
the roof is strongest at the ridge.. as long as the walls are tied by the ceiling joists.
if they're 2x8's should be no problem....
repost your drawing and show the ridge(s) as a dark dotted line..
is the small ceiling a room addition ?
Mike Smith Rhode Island : Design / Build / Repair / Restore
Edited 1/5/2004 8:07:15 PM ET by Mike Smith
This drawing should put things in perspective, it's a quick draw of the entire house. Roof is very similar to your example, Mike. Ridge runs down the middle.
One end of the beam sits on the corner where the kitchen, dining room and living room meet, the other end sits on the bath wall.
I agree, there shouldn't be much load other than drywall until I get my fat butt up there and make it move. We are expecting 8-12 inches of snow tonite but snow is not common here (Seattle). The joists are not 2x8s they are 2x4s as well as the beam.
should be ok... make sure you have a tie across the beam.. the short joists should tie to the long joists so you have continuous ceiling joists from exterior wall plate/rafter heel to exterior wall plate/rafter heel....
in other words those joists are also functioning as low collar ties.. make it soMike Smith Rhode Island : Design / Build / Repair / Restore
Considering that the intersection is made up of only a 2x4 chances are the ridge is insufficient aswell, so hanging from the ridge is probly not an option. you best bring in an inspector.In the long run replacing the inadicate2x4 with a pair of 2x8s or better is your best plan after all you want to be safe even in a hurricane or the like.With that in mind you best have an evaluation of the whole building.lets put this old clichay on the drafting table ...dont do it unless your prepared to do it right.
keep your claw away from the head
Drop some hangers from the attic.
Excellence is its own reward!
Pif,What do you mean when you say attic? From the rafters to the 'beam'? Won't that be a bit bouncy too?
I did a job like this where there was a room about 28x32 with a five inch sag in the ceiling. We hung a beam in the attic according to emngineers specs. There were three stories in between and we ran cables and rods down to th ecenter beam in the ceiling below, keeping them in the walls. Then jacked and cranked until all was straight.
It is an engineering job, not seat of the pants..
Excellence is its own reward!
Isn't that, in a sense, similar to a 2x8 on top of this 2x4? I was thinking 2x8 was enough for an 8 ft span based on past conversations. I suppose threaded rods would help tight it up. What about a U-bolt system?
This one isn't as complex as yours. Not sure if my drawing is making sense but what it is showing are the joists in the attic, looking down at them, which are all sitting on top of the walls, of course. The heaviest line between the two boxes is the 2x4 I am referring to. This is single story too.
The more I think about it, the more I believe its just a drywall problem. Run a string and see if it is sagging, if not just redo the drywall. There are always cracks between old ceilings an new ceilings because there is a continuous joint that has nothing across it to tie together. Houses with cracked drywall ceiling do so cause the homeowner ran the drywall paraell with the joist or did not stagger the joints.