I am planning to build a superinsulated house. I would like to use I-joist floor trusses as wall studs to obtain a 12-inch thick wall. Does anyone have experience with this application?
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No, but I remember seeing article(s) in the mag, that really caught my eye....can't remember which....maybe 1990-1994?search?
"If 'tis to be,'twil be done by me."
Thanks. - art
It's generally better to build two 2x4 studwalls. That eliminates any bridging and gaps in the insulation.
That certainly is an option. hanks. - art
First - I-joists are NOT trusses.
Second - I doubt any of the I-joists manufacturers would go for this. You'd probably have to find out which brands are available in your area, and contact the engineering division of the manufacturer.
Third - Even if you get the approval of an I-joist manufacturer, your local building department may not go for it. Check with them before you get too far along with it.
I have checked with manufacturer's associations. They haven't analysed I-joists as studs and they didn't seem too interested in doing so. This may not go anywhere. Thanks. - art
>> First - I-joists are NOT trusses.Then why do Weyerhaeuser / McMillan call their version Trus Joists?Or to ask it another way, who has the authority to decide what can or cannot be called a truss?
"...who has the authority to decide what can or cannot be called a truss?"
I do.
O.K., seriously - You make a good point. It's not really up to me to decide what they're called.
But to me, a truss is a series of chord and web segments connected together to form a structural component. An I-joists is a whole different animal.
So it's just a personal pet peeve, I guess.
The people who get on in this world are the people who get up and look for the circumstances they want, and, if they can’t find them, make them [George Bernard Shaw]
Note that they don't call them Truss-Joists. Thereby they avoid any possible claims of false advertising.
I-joists are not made to take loads in that direction. Call the companies that make them.
I think that you are talking about what is called a Larsen Truss.
http://www.motherearthnews.com/arc/6050/
No, Larsen trusses hang on the outside of a build and are used more as retro fit. - art
Here's another vote for SIPs. No thermal breaks and high strength, plus they make a house very quiet.
D&L
Thanks. - art
I did some reading about superinsulated houses.CMHC was running a test house in Edmonton Alberta. The weather was forty below (same in both systems). The houses back up heater wasn't even turned on (the backup heater was a tiny little $25 space heater)
Of course when I say superinsulated I am referring to a standard that sets certain levels of insulation. Designed to be heated by occupants and lightbulbs. (just don't get compact flurescents ;)I will look for the link to that article if anyone is interested/Last year I didn't know what any of this stuff meant.
That's the type of house I would like to build. It costs more to heat domestic hot water than to space heat the house. - art
depends on the compressive loading. They are not intended to be in compression, and lacking adequate shear bracing could possibly buckle under the load..unlikely, yes, but could.
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It looks like an analyses would be in order before they were used. Thanks. - art
Have you considered using SIP's? The effective insulative value would be higher, they are designed to handle these types of load, and you won't have 12" thick walls to deal with.
Just a thought.
Jon
That maybe the easiest solution. - art
Why don't you fill in your profile, so we can see where you live.
A superinsulated house might be a good idea for Calgary, but a waste of money in Tallahassee.
I live near Bangor, Maine. With the price of oil this year, superinsuled will pay for itself in short order. - art