Using fewer 2x4s in framing
In a FHB article “The Future of Framing” (Oct/Nov. 2005) many changes were suggested to reduce the amount of wood framing in an outside wall, thus reducing thermal bridging through the framing, increasing % of insulation in the wall and saving trees and money as well. When I showed the article to our local (MA) building inspector he told me I would have to prove that the suggested changes would satisfy Building Code requirements.
Anyone have experience doing this or suggestions as to how to go about satisfying code requirements when using these innovations?
A few examples of the article’s suggested framing changes: a- header hangers to eliminate jack studs; b- no headers in non-bearing walls; c-single stud at rough openings; d- no cripples under window sill.
Thanks
Charlie
Replies
If it's the same article I remember, the author was Joe Lstiburek of Building Science fame, who also lives in MA. I suggest you talk to him via his website http://www.buildingscience.com
The best way to use fewer 2x4 in exterior framing is to ... not use 2x4. 2x6 24"oc is as normal and usually as 2x4 used to be.
My initial response is where has this BO been? 2x6 24oc and advanced framing has been in use, now for 30 years!! I just finished a house a couple years ago. 3x5 windows in gable end walls ... no crip and no header ... just horizontal stud piece. And yes, the inspector saw it, looked at it, questioned it (briefly) and passed it.
We started using some of the advanced framing techniques when I built my first house in 1980. Traditional (i.e. old fashioned) framing wastes a LOT of material for little or no structural reason. And in exterior walls, this translates to large energy penalties.
2x6 24 oc and advanced framing will use less lumber than 2x4 16oc using old techniques. Less labor in assembly, too.
Your BO needs to get himself up to speed. You shouldn't have to be the one to prove this to him. It's like ... 'prove to me that 2 16d nails is right for this stud' ... absurd.
rough framing
One thing I remember about this new practice is a question about how to hang the trim. Some also have posted questions looking for wood that isn't there. You should plan carefully how your finish is going to be handled. One way may be using screws for outside trim and preassembled trim for interior. Hope it helps.
k1c makes a good point. Blocking, I found out is a BIG DEAL! I did my own house. I spent a lot of time adding necessary blocking only to find out I was still short in some areas (often having nothing to do w/ an insulated wall).
You can't overthink blocking. Eliminate the structure, but make sure you have all the blocking you need. Kitchens/cabinets, stairs (railings and skirtboards), door trim, window trim, curtain rods, towel rods, etc etc etc.
You can often back drywall at corners and such w/ 1/2 or 3/4 plywood and maintain high insulation levels. It's a great way to consume a lot of scrap that many contractors fill our landfills with.
Where do You Want the Blocking?
Justin Fink wrote a good article on blocking a few years back: https://www.finehomebuilding.com/how-to/articles/where-to-put-solid-blocking-in-every-room-during-framing.aspx?ac=ts&ra=fp
Check it out.
Dan
Some great tips. Good advice for framers who want to do a good job ... but they need to think beyond their trade of framing and think: electrical, plumbing, finish carpentry. Wow, there is just a lot to deal with. The framing is really pretty straight forward.
I realized doing my house that framing builds a solid foundation for lots of things. Good framing means easier door hanging and drywall hanging, too. I could see the benefit of selecting the crowns of studs to match when framing a wall. I saw the benefit of good plumb walls and nice square openings. Who cares if the window opening isn't quite square or plumb ... that's what shims are for ... yes and NO! Who wants to ship drywall to make up for that stuff!!
Frame good. Frame straight. Do a dang good job and you end up w/ a much better house no matter which way you slice it!
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and do not forget a good design layout.. Building a home on a 4' or 2' grid rather than these 25'3 1/2" walls can save a lot of building materials.
We deleted the old framing technique where walls would intersect and you used to build a u-shape 2x section to lock the walls together. Rather than that we nailed 2x4s horizontally at 2', 4' and 6' centers between studs where the other wall intersected.
This gives you all the blocking you need for drywall and you save 2 studs on every intersection. That is quite a saving in a whole house
I've used simple a 2x6 flat on the backside of the intersecting wall. Quicker to install, maybe. But the idea is the same. Your method sounds like it 'ties things together' better maybe.
Charlie,
Did you see the article hint on the home page of Finehomebuilding.com? More of the same. Amazing how much wasteful framing we got into the habit over the many years when lumber and energy was cheap. It's simply time to build a bit smarter while maintaining structural integrity. It requires a bit of shift of thinking, but so does my new TV, microwave, computer, etc. We seem to embrace THAT new thinking but we balk at changing the ways we build? Go figure.
Are you talking about the Inspector game?
https://www.finehomebuilding.com/pages/the-inspector-twentyone.asp
If so, I shot that photo on the same trip that I was shooting the photos for the Lstiburek article (The Future of Framing). One oh my hobbies to to go to job sites on Saturday and Sunday to get photos of how not to do it (reverse-lapped Tyvek, over-framing, bad insulation details and bad flashing).
You're absolutely right that this is not a new thing. Fine Homebuilding published an article about it waaaaay back in 1993 by E. Lee Fischer of NAHB Research center (https://www.finehomebuilding.com/how-to/articles/economical-framing.aspx?ac=ts&ra=fp). We talked about it in one of the lunchpai podcast series, Still Framing Like it's 1969? here: https://www.finehomebuilding.com/item/12151/podcast-still-framing-like-its-1969
Great to hear that you started doing it so long ago; keep up the great work.
Dan
Less framing material
As someone mentioned that this is not new, I remember MOD 24 back in the early 70's. Not all parts of the country have adopted the 2009 International Residential Code and the requirements to meet seismic and wind load vary from place to place but the use of less material in framing by using a single top plate, alternate or no headers, lining up rafters and joists with studs and eliminating trimmers and some cripples are all addressed prescriptively in this Code and is applicable in those jurisdictions that have adopted it..
Dude, you seriously need a new engineer and BO!! I put a 2x6 header ... FLAT ... in my gable end wall windows under the full scrutiny of the BO ... in fact he scratched his head a bit and we had a discussion ... then he approved it. And in case you think he's probably a wimp, I assure you .... he's a seasoned builder and he tends to go to the high end in his decisions.
Even in earthquake country, much of the framing is excess that provides no structural benefit to speak of.
But like you say ... sometimes you just do as they say and not argue ... especially if you personally can't grab a copy of the code and show him where it allows you to do something ... you have to be pretty code savvy about the topic to do that ... in which case you wouldn't have submitted your comment.