I’ve got a general question about the span on ceiling joists. A friend of mine is remodeling a rental unit (a bungalow), and to allow more room he added a ceiling area above the kitchen/bath so that there can be a sleeping balcony (of sorts). The height at the ridge line is probalby 5 feet, and it’s tight, but for sleeping that’s fine.
The question I have is that he framed up the ceiling joists by using 2X4s, and the span is probably 12 to 14 feet. The 2X4s are 16 inches OC. Is that acceptable, given that there will be furniture and people above (bed, perhaps a short dresser, and perhaps two people sleeping)? I’m not a framer and don’t have the proper reference material at home for this. My expertise is in solar heating, but I’ve done lots of other stuff as well. Thanks in advance.
My gut reaction is that this looks awfully flimsy and should probably be 2X6s or 2X8s. but I just don’t have any idea.
John
Replies
I wouldn't go up there and I wouldn't go under there either. Remove it and build it right.
My thoughts, exactly. I saw the SpanCALC link in another thread shortly after posting this one and from what I see there it looks like the 2X4s can legally only span a little over 7 feet. If they go to 2X6s it looks like the allowable span is almost 12 feet. Would you agree with those numbers? This was for floor joists (30 live/10 dead, sleeping rooms & attic), D. Fir, select structural, 2X4, on 16 inch centers.
John
2x4 spanning 12-14 16 oc
no way in gods green earth would I be up there, under there or anywhere close to where all the stuff is going to land when it does come down
Come on, guys. The problem is stiffness, not strength. L/360 for a 7 foot span is .23 inches. Double the length and the deflection goes up by 8, so you get a 2 inch deflection over 14 feet. That's ugly and uncomfortable, but it's nowhere near failure.
Is there an emergency egress window in this loft?
Bob
No window (upstairs), at least at this point. I think the plan is to put in a dormer window, which probably would add egress.
Are you thinking escape from a fire, below?
John
I bet he is going to use extension ladder for getting to this heaven on earth.
Actually, there is a fairly attractive (yet steep) stair he's built and which helps support the front section. The bungalow is relatively small, and the idea of a sleeping loft is great, but I don't like the "flimsy" framing. I'm not sure it'll come down, but it'll sure feel springy and strange.
John
It'll fail in several ways, with the cumulative effect being disaster.
It will begin to sag uncomfortably immediatly. That is failure in itself but noit a killer.
But anytime anyone moves up there, it will be bouncing. That and the residual vibration will place three to ten times as much stress on the end fastenings as a dead load alone will. You haven't mentioned how he fastened them. Since it's obvious that he doesn't know what he's doing, it's apretty good guess that he only has a couple spikes running them into rafters and maybe not bearing on anything. If so, the bounce will split the wood out and let it all down.
Another concern is that he may put a dormer in for a window. to do so, he probably needs to double up a couple rafters. By already having these 'joists' installed, he has complicated that job so it will be easier for him to ignore that problem too. That will lead to a potential for the roof to sag. Also, if these are hung only on the rafters, he is now exceeding the designed load for them.
Can you see where I'm going with this?
His name isn't Jack is it? That would make this the house that Jack built and he might soon find himself in need of some good jacks.
;-).
Excellence is its own reward!
The loft joists are hung with 2X4 joist hangers so that part is very strong.
Not sure how the loft joists affect the dormer window (assuming it goes in). The new joists are hung below the top of the side walls to give more headroom (upstairs). My guess is that they're at the 7 foot level.
John
Since they are hung down in the wall, they would not affect the rafters. What are the joist hangers fastened into?.
Excellence is its own reward!
I'm pretty sure they're hung from a 2X4 which is attached to the wall studs. Not sure if it's bolted or nailed ... probably nailed.
John
No window (upstairs), at least at this point. I think the plan is to put in a dormer window, which probably would add egress.
Are you thinking escape from a fire, below?
Yes. Without an emergency egress window, if there is a fire in the house ... anyone in that loft is doomed.
If you can't see out, you can't get out.
Bob
Yecch. This is the kind of thing that gives landlords a bad name. Five ft. to the ridge is way too low to be a "habitable room" by any building code.
No way are these ceiling joists if people and furniture are going to be up there. They're floor joists, so putting aside the fact that this shouldn't be done at all due to the height, they should be sized as floor joists. Around here you'd need 2x10 on 16" centers for 14 ft Or using 2x8 on 12" centers would be OK for 13'-3". This is for #2 Doug fir.
You say above the "kitchen/bath". Is there a wall between kitchen and bath that supports these joists in some way? Or is it like that Seinfeld episode where Kramer showers with his vegetables? ;-)
-- J.S.
There's a wall between the kitchen and bath, so the joists (floor joists, I agree, are what they should be sized at) don't span the entire width of the bungalow. I suspect it's about 12 feet, perhaps 14, for the width of the kitchen. It could be less ... just going by memory. But if it's less it's not much less.
I just picked up on the idea that this is a rental.
It takes one kind of a fool to take a chance like this with his own life and goods.
But it takes a different kind of fool to make a profit from putting someone elses life in danger. It's called criminal behaviour.
Most places have stronger policies about rentals than they do about the regular building codes. This project is illegal three ways when you count morallity.
Excellence is its own reward!
Dude, the 2x4's are fine, now throw some 1/4" durock over it and lay some 12" tiles down to make it purdy. I am assuming that no building permits have been pulled for this fiasco. If you do have a 2" deflection in this floor he is going to spend more money on plaster repair for the cieling underneath everytime his tenant gets lucky than he would spend purchasing the correct stock. Spring for the 2x10's if he insists on gaining this "living space". Why bother using hardware to attach a "joist" to a ledger which is only fastened with nails? Tell your buddy to rethink this thing before he closes in any of the rough framing...please.
If you want to sleep well have your friendly neighborhood building inspector swing by and have a look-see, he'll let you know what you need to do if you still feel you need another opinion. I hope your buddy is open to advise.
Edited 2/5/2003 11:04:32 PM ET by dieselpig
Thanks, everybody. You've confirmed my initial suspicions that this was way, way undersized. I've passed along your joint concerns. Can't do much more than that because it's not my project.
John
I've passed along your joint concerns. Can't do much more than that because it's not my project.
I gotta disagree with this line of thinking. If it were me, and my "friend", I would make damn sure to do whatever it took to protect him from the possible impending catastrophe that may be coming his way. And if I couldn't convince him to fix it after it was explained how dangerous, immoral and irresponsible this is, I'd report it. I wouldn't want to live with myself if something drastic happens to whomever he rents that crap to and I did nothing about a dangerous condition I knew about.
But knowing that most friends have similar values, and you seem to be concerned, I'm sure he can be convinced to see the error of his ways.
Edited 2/6/2003 11:54:25 AM ET by Mugsy
Can't do much more than that because it's not my project.
Get the keys to place, a sledge hammer a step ladder and a pry bar :)
When he has to redo it, make sure he redoes it right
This thread has been by far,the funniest I've ever read here.If this "builder" doesn't qualify for a Darwin award,I'll nominate him myself.
Funny yes, but potentially tragic.After all, tragedy is when it happens to you; comedy, when it's someone else.