I-joists work fine on this spacing, but to my knowledge, no one makes insulation to fit this spacing. A consideration if the floor needs insulating as in a crawl space. HTH
I-joists work fine on this spacing, but to my knowledge, no one makes insulation to fit this spacing. A consideration if the floor needs insulating as in a crawl space. HTH
Scott; There's a couple different schools of thought about insulating your cavities between floor joists. One way, and the way I do it, is to insulate the crawlspace walls with 2" foam. Then insulate the rim joist with at least R19. And, don't insulate the floor at all. This way during the heating season, you don't wind up with cold floors. I also use the self closing vents for the crawlspace. Those have louvers that have a bimetallic element attached that close the vents below a certain temperature. Around 45 degrees I think. You also run less risk of frozen pipes too.
There are other ways, such as sealed crawlspaces, and some others. But what I described as me using seems to work well, ventilates during warm humid weather, and the foam is required upnorth in my spot in Michigan. [img]/forums/images/icons/grin.gif[/img]
Trucks are red, Tractors are blue.
My current house has R19 or thereabouts in all joist spaces and I have the warmest floors I've ever had in winter. I have manual vents which I close when the temp drops to about 35 deg. at night. Much warmer than that and they need to be open to hinder mold formation.
I (perhaps unfounded) really don't trust the automatic vents as they don't open all the way till about 70ish degrees...
If one wants an FHA loan, they require R19 in all the joist spaces and either chicken wire or deer netting to hold it up.
Hi Scott; FHA and the VA require a few different things from the standard codes. Theres nothing wrong with that, but there is a lot of "new" technology it appears they don't recognize yet. Not only the financiers, but some of the local codes can get a bit odd too. Don't take it wrongly, I'm glad we've got codes. I've been in a few places that were built by the owner, and some of the logic was that when they built grandpas garage back in '56, they didn't build like it is today. And that can be a good thing. [img]/forums/images/icons/grin.gif[/img] I won't mention the code for fear of insulting anyone, but our Government has a code that supercedes any other, and really is a very substandard code. No, I don't mean FHA.
I'm still a little leery on those autovents too! [img]/forums/images/icons/wink.gif[/img] I still go around and make sure they open and close. [img]/forums/images/icons/crazy.gif[/img] [img]/forums/images/icons/grin.gif[/img]
Please forgive my seemingly wandering. [img]/forums/images/icons/wink.gif[/img]
Trucks are red, Tractors are blue.
The little diamond marks on the tape let you leave out one stud per 8 ft and divide up an 8 ft piece of sheet goods perfectly. It works fine and if all mechanical engineering considerations are appropriately handled it is a fine practice. I have read a book by a civil engineer who built a series of energy efficient homes which he instrumented to gather data. One of his claims was that since 2x4 studs are often "loss leader" items at building supply outlets they are far more economical to use than 2x6. He builds his walls out of 2x4 on 24 inch centers but builds TWO outer walls on 24 inch centers with the location of the studs staggered. He can then adjust the spacing of the double wall to give room for a high R-value using economical F/G batting rather than foam or whatever.
His claim is that he can frame a house with double walls using 2x4 studs on 24 inch centers for about the price of framing it with 2x6, especially after factoring in the cost of high R-value insulaltion. Framing cost isn't the whole story, the double wall allows for economical super insulation. Another benefit is the "THERMAL BREAK" as there are no heat conducting paths through the studs since they are staggered and have batting behind them. Insulation that gives R-50 may still result in a wall with R-30 performance due to the conductivity of the studs in traditional framing and other common problems like infiltration and so forth.
[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]
"I'm not from your planet, monkey boy!"
I definately agree that how the goobermint does things has little to do with what makes sense. [img]/forums/images/icons/shocked.gif[/img] [img]/forums/images/icons/grin.gif[/img]
Duane; Sorry about the hijack. [img]/forums/images/icons/blush.gif[/img] For more on where this thread ended up, please see hijacked on center thread. [img]/forums/images/icons/blush.gif[/img]
Trucks are red, Tractors are blue.
Pat, I would sure think that building a double 2X4 wall would add a considerable expense on the labor end. With 2X4's at anything over 8', we have found we spend considerable time straightening walls. Whether its whaling them, planeing them or both. To have to do two would add many extra hours. Just the planning for openings would have to be coordinated, probably best done at the plate stage. We have built double interior walls for sound purposes although there are even easier ways to deal with that nowadays. Anyway, interesting idea and I am all for anything that helps reduce cost and also is more effective.
RaT, Of course there is some increase in labor, a moderate one time expense. Inexpensive super insulaltion reduces the recurring charges of utilities for the life of the house.
It will make a significant difference to the owner's wallet (and the planet) over time if you superinsulate up front. The double wall gets you there with good but cheaper insulation technology. Even with 2x6 (or 2x8) walls and spray in plae foam (very costly) you can't match the R-values available with ore economical materials with significantly greater thickness.
[img]/forums/images/icons/smile.gif[/img] Pat [img]/forums/images/icons/smile.gif[/img]
"I'm not from your planet, monkey boy!"
Pat, I guess this is where you make the price/perfromance decision to go to other insulating systems as well like ICF etc.
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