Not having a lot of framing experience, I’d like to get some opinions on my situation. Ok, let’s see if I can articulate my questions.
So, I have a second floor bedroom that I would like to open up the ceiling to the roof on. The roof is supported by roof joists 32″ on center. There are trusses 16″ on center (every other one ties to a roof joist) that the ceiling of the bedroom is attached to. So, the questions are … Are these trusses/rafters structural? And, can I remove some of them, say every other one (so, I would have a truss/rafter every 64″) without my roof collapsing?
Thanks,
Jes
Replies
you have a picture of this???
" And, can I remove some of them, say every other one (so, I would have a truss/rafter every 64") without my roof collapsing? "
You will seriously comprimise the structural integrity of the building if you do that. But the roof might not collapse for a while yet!
Get your ideas together, then call on your local engineer to figure out a solution, then take it all down to city hall for a permit for it. Big job you are looking at to do it right.
I agree with 'westcoast'. But there's a lot more we all need to know. Firstly, what are the reqs for insulation inyour area? (Fill out your profile, please, and that'll help others). How deep are the rafters? do you need to add depth for insulation? Are they strong enough to support the weight of drywall? Could you span the midpoints with purlins? Etc.
Are you using the word 'truss' when you mean the ceiling joists act as a bottom chord, "tie" is a better word. Now, you just MAY be able to remove them IF for instance you double them up...I've had the blessing of my BI on one occasion for this, BUT you need to talk this over with your guy and/or an engineer.
cheers
***I'm a contractor - but I'm trying to go straight!***
We call those roof joists, collar ties where I'm from, To go and haphazardly remove one or more in my opinion is a serious mistake. They keep your walls from spreading out and therefore your ridge from dropping. It is possible to open up a ceiling though. You just have to come up with a way to hold the roof together. You might be able to raise the ties or post the ridge. I would not attempt these without involving someone experienced in structural design.
If we had more specific info we might be able to give you a little more advice but without being able to see the structure ourselves it is difficult to make a real sound judgement. We can only steer you.
Not meaning to be rude, but you don't have a good enough handle on the proper terminology such that anyone can really give you a quality answer. We can only make educated guesses about what your current roof framing configuration is. Go up in the attic with a digital camera, take a pic, and post it here and you will get some more authoritative responses.
Good advice. That and a structural engineer.My guess is he's got rafters @ 24" o.c., and ceiling joists @ 16" o.c., and they tie in every 4'. Which is a pretty standard framing configuration, at least around here. 32" o.c. doesn't sound right, unless he's got 2x t&g roof sheathing, or something like that, which again seems unlikely.So if my guess is correct, I'm thinking he can probably safely remove the c.j. except the ones that tie-in, leaving those every 48". Structural engineer is the final answer here. Needs to address the insulation/ventilation issues also.
Go up in the attic with a digital camera
Or a regular camera, and pay the $2 extra for a photo CD, "we" can get you likns to irfanview to get the images to Us.Occupational hazard of my occupation not being around (sorry Bubba)
Thanks for the information guys.
Your answers are pretty much what I was afraid of, and it is unlikely that I will be proceeding with the part of the project that I tried to outline above.
Just to fill in the picture though for anyone who is interested ...
The rafters are indeed 32" o.c., and the ceiling joists are 16" o.c. with every other one tying in to a rafter (properly, a collar beam or a tie). The rafters are 2x4, and the sheathing is tongue and groove (it is an old house.) If I were to remove every other tie and the ceiling joist on either side of it, I would definitely double up the ties at the remaining locations.
Maybe if my architect friend responds to my email, I will get a pair of expert eyes to look at it in person. Then again, the effort and cost here is probably greater than the rewards.
Oh well.
Jes
sub it out and watch 'em like a hawk..
Jesse,
Don't take this the wrong way, but if you don't know the proper nomenclature of the framing members in question.... you probably don't have any business being the one removing them or trying to figure out if you can remove them. Help from the internet or not.
Get your architect buddy to give you a good handle on what's going on there. Have him explain the forces involved on each member and the appropriate terminology. Let his come up with the prescription.
Then if you think it's a worth the time/effort/money, you should know enough about the situation to decide whether or not you should do it yourself or hire it out.
Hope it all works out nicely for you though.
>> The rafters are indeed 32" o.c., and the ceiling joists are 16" o.c. with every other one tying in to a rafter (properly, a collar beam or a tie). The rafters are 2x4, and the sheathing is tongue and groove (it is an old house.) <<
Wow - that is quite a minimally supported structure, or at least by modern standards. Not to wory though - it's been standing all these years, but personally I wouldn't consider removing too much of anything...
This web page shows a good pic of a collar tie: http://harvey.wisd.net/~efricks/CONSTRUCTION/ROOFING.htm and will help you understand the difference between a collar tie and a ceiling joist.
Matt
I will get a pair of expert eyes to look at it in person
Yeah, it could be that you could get a "cathedral" ceiling effect by having pitched ceiling joists that would not rise up higher than a correctly spotted collar or rafter tie.
Given the structure you have described, to get the ceiling up under the roof would likely mean installing brand new rafters of much greated depth (2x8, 2x10, etc.) if only to get enough insulation depth in there. That would get rapidly complicated, too, seating the new, deeper rafters might create a need for rafter ties that a persent collar tie meets (even if only "mostly" by modern standards).
It may be that a coffer or tray ceiling would be better for the room in question, too--that's a different sort of structural answer, too.Occupational hazard of my occupation not being around (sorry Bubba)