OK, right up front I plead framing impaired … my background is design and trimwork … everything that happens before excavation and after the house is dried in and the drywall is hung. I’ll have a lot more involvement in an upcoming project, and could use a few lessons. Here’s the deal …
Project is a tri-level on a steep sidehill … walkout in the back. Exterior walls will be done with SIPs, as well as 5 of the 6 levels of flat roofs. Floor joists all 14″ I-joists on 16″ centers w/ 3/4″ subfloor. Walls are nominal 9′ all three floors.
Two true cantilevered decks, and two cantilevered deck overhangs, all supported with steel, W10x45 in some cases, and W10 x not-so-heavy in others. Steel is all buried in the 2nd and 3rd floors. If anyone is aking the question, “Why don’t you use a W12x30 section, much lighter?”, the answer is that the steel section has to be low enough to get some pitch in the deck surfaces for drainage.
On to the question … given that I have to marry the elevations of steel, framing, and SIPs together, I need some basic framing help. Am I correct in assuming that the general framing sequence for one level will be bottom plate, stud, double top plate, 14′ I-joist, and 3/4″ deck? I’m trying to arrive at the most cost-effective method to frame this thing to end up with +/- 10′ floor to floor. Once I understand that piece, I can specify elevations for the steel and heights for the SIPs. I’m guessing a 9′ standard stud is the route to go (or not?), but I’ll go so far as to plead ignorance on how long they are.
One issue to deal with … I’m hoping the steel elevations will remain static, but I can foresee where the rest of the framing might shrink, causing drywall problems at wall-ceiling joints. Thoughts??
Well, actually two issues. Given that I have flat SIP roofs (10″ thick panel w/ I-joists as splines), has anyone ever dealt with how to keep the interior partitions from bearing on the panel skins? They’re essentially degned to carry the load at their perimeter, where there is some lumber. If the panel passes over a non-bearing partition, should that partition be kept a touch short? And how does that case affect drywall joints?
So there’s the scoop. My thanks in advance for your help!
Replies
OK, learned a little something in the last few minutes. I'm going to be looking at 10' 3-7/8" floor to floor, right?
Bemw,
If you want to end up with a standard 9' wall which is actually 9'1 1/8" prior to floorcovering and ceiling drywall you can buy precut studs 104 5/8" long. I'm not familiar with the roof panel system you are talking about so I can't help you there. To my knowledge you can't buy a precut stud for ten foot walls but check with your lumber supplier to verify that. Good luck
Mark
Nine foot ceilings is what I'm looking for, hence 10'+ floor-to-floor.
Thanks!
We're a northern VA yard, started stocking 2x4-116 5/8" about a year ago. Volume is slow but building with 104's outselling 116's at a rate of 25 to 1 this year. That's not lighting the world on fire but we'll keep offering them here. Can't speak for other regions...have to wait & see if they catch on or not.
Al
...the general framing sequence for one level will be bottom plate, stud, double top plate, 14' I-joist, and 3/4" deck? Yes, and the second top plate goes on after the walls are up, lapping joints, helping to hold things together as you square.
... I'm hoping the steel elevations will remain static . . . Sounds right, but if you're using steel, you're not really mixing things such as steel joists and lumber rim joists, so as long as it's just tying one to the other, if I read you right, the house goes up and once framed the deck structure gets attached. At which point you've already specified an elevation and the GC takes a read based on what's there vs whats on blueprint. I'm not sure I see the issue. You'd specify where it is supposed to be and it's their game to make it right, which always = adjustment of plans vs reality. Lumber shrinks, sure, but unless I really missed your explanation, I don't see this as an issue.
As to the SIPS, I'm out of my element, but don't see how the partitions would bear on the roof skins significantly. If you see it, research log home building and how not only walls, but plumbing connections are made to move. The partitions are kept short and anchored with bolts, with enough gap between the top plate and the floor above for movement. Drywall goes to the top, stops at the gap, and ceiling moldings are often used, attached to the ceiling, so when the ceiling drops 1/4", the molding just slides down the wall.
That ain't everything, but it's what I got.
Thanks for the info ... my hand-wringing around the issue centers on the fact that the SIPs will likely be ordered before the steel is up ... this makes field measurements a moot point. The stemwalls have to be dead nuts, so the steel and first floor deck can be dead nuts, so the SIPs will land dead nuts.
I take no issue with the fact that stick framing, thoughover 150 years old, is flexible in that it allows you to take up the slack for just about every kind of error. I'm a believer in SIP technology, but with it comes a whole bag of up-front planning that you can get around with stick-built.
Thanks again for your reply!
Can I make a point here?
SIPS while they are easiest if cut exactly correct, can be field modified easily.
I do it to my timberframe a lot.
Ma nature always seem to want to throw a twist into a timber and when something winds up being a little off, you just modify to fit. Maybe not as easy as cutting a piece of plywood but not a whole lot harder.....
Yeah, I'm with you there, that they can be modified, but that would take extra work! I just have a real aversion to that.
Thanks for the comment!
Check the "Wall Height" thread in this section. 104 5/8" studs may or may not be readily available in your area.
-- J.S.
I'm not certain about the rest of your house but SIPS will easily carry any load you've listed. they are considerably stronger than a stud wall.
you could possibly eleminate the studs completely (except for interior walls which I'd be tempted to do in steel since I hate both crooked walls and the effort it takes to get the semi green studs to dry into a nice straight line)
I don't have any concern about the SIPs carrying the load. That's not really the issue. The point is that some SIP manufacturers don't want their panels bearing on a wall other than at the perimeter of the panel ... they want to avoid the chance of an excessive load, like a 6' snowfall, causing the bottom skin of the panel to deform where it lands on the top plate.
Steel framing? Sounds like a plan, but I'd have to live in the real world where there are crews to do that kind of stuff. I'll have to stick with crooked remnants of trees.