Double Stud Wall Framing for Passive House

Out at our Passive House, we are framing double wall exterior walls. Check it out as we walk thru the details

[JL-hnhi]

The interior comfort level with double stud is A+, in my experience. Love it.

[hodesto]

Great content Steve. Are the numbers crunched to see what more cost effective putting added insulation on the outside or as you did in that house. A double studded wall. I like the double studded approach. Wish big red can show some cost comparison.

[connormalloy]

Great video, Steve. Thanks for sharing this one

[mrmike]

My son has been building double stud walls for a few years now. Outside wall is 2x4 16” on center and that wall is spray foamed. 2” gap and than inside wall again 2x4 16” OC but of set 8” with exterior wall and that gets Rockwool insulation. Now for a question I have for you. Have you had drywall screw heads start showing up over time? First 3 houses he did, so he came to me and asked way that might be happening. I thought about it for a bit and figured out that the inside stud wall was twisting because nothing on the back side stopping it from twisting. Put blocking half way on wall and next 4 houses and no problems so far

[danielstover]

Hello Steven! When you have the opportunity, would you please expand your explanation of the possibility of a double negative of a thicker a 24" double wall in a cold climate. You commented something about making the exterior side of the wall colder and the possibility of greater issues. Your content is greatly appreciated and I have watched all of your videos. Thanks for sharing! Always liked and subscribed... 👍👍👍👍👍

[scorpio]

Question: Would it make sense to stagger the inner and outer studs, potentially increasing the thermal break from three inches to 6.5 to 8.5 inches, in most stud locations? Or is this effect negated by something else? Great video.

[corvetteboy]

If a reflective form boad was placed in that 3 in gap, would that hurt the wall in regards to drying?

[siriosstar]

OR you could try the following . my house is a log/block house . the laminated 'logs ' are 14 cm thick with 14 cm of wood fiber insulation on the outside followed by verticals furring strips and wood paneling over that . the space in between the FS acts as an air vent to remove any moisture build up . no vapor barrier is necessary as the entire wall assembly is vapor permeable . The mass timber on the inside regulates humidity and tempeture swings making for a very comfortable atmosphere . The air blower test was almost at a passive house level . No air to air heat exchangers are necessary as the entire structure is non toxic and non off gassing.
opening a window for five minutes is sufficient to refresh the room . heating is done by a two ton soapstone down draft oven .
A three hour burn is enough for two days at 72
degrees or warmer at 32 degrees outside .
The exterior walls can be erected in about two days including g roof framing . the lower labor cost offsets the higher price for the timbers .

[ianupton]

Curious what the “need” is for the 2X6 on the exterior wall? Would 2X4 interior and exterior be structurally sufficient? Potential for a larger thermal break where the stud section of the wall would have greater R value, not to mention less lumber.

[DragonTalkShow]

A lot of people naysay about putting OSB on the outside of a double stud because of its relatively low permeability. Do you see that being an issue at all or is that overblown? Will this walk use a vapor control membrane on the interior to slow moisture drive during heating seasons or is it fine without one?

[teraxiel]

Why the 2x6 exterior wall? Is there really ever any reason to do a 2x6 exterior wall in a double wall assembly?

[granthmeek]

Love your video! QUESTION: to be clear, is the 3" thermal break filled with cellulose? Also, isn't he true weighted average R-value of the wall significantly reduced by the large window?

[aldoogie]

For the recessed windows, are you doing nail on to a 2x that's connected to the sheathing? or are they blockstyle windows connected directly to the sheathing on the inside of the window buck you've designed? ( LOVED THIS VIDEO!!, amazing details!)

[afraidknot]

So…where’s the fire stop required in most areas?

[RogerWilsonTodd]

Steve, what factors should be considered when choosing between double-stud and staggered-stud?

[marcbellucci]

Great video, thanks! Hey, do you have a favorite type of house building method I.e. wood, metal, ICF, concrete or concrete block etc.?

[brianhewlitt]

That was great coverage on dbl stud walls Steve! And glad you talked about how the "dew point" moves within the wall assembly and having to pay attention to potential condensate. I was wondering your view on offsetting the 2x6's and 2x4's centres (ie by 12")? Effectively that would produce greater depth of insul in the cavity between the two walls (ie., 6-1/2" of insul between the inside face of a 2x6 and the vap barr / drywall, and 8-1/2" of insul from the front face of a 2x4 to the exterior sheathing, respectively). Obviously most applicable on long running walls, but do you think that would add materially to the R-values, rather than simply a consistent 3" thermal break? Worth the bother?

[RogerWilsonTodd]

Steve, what factors should be considered when choosing between these two 12" double-stud walls: 2x4+5" gap+2x4 OR 2x6+3" gap+2x4?

[jonathanmilton]

Can you add exterior insulation to this wall to stop the problem of the sheathing getting cold?

[NorthernCamping]

Why do 2x6 for the outer wall? Why not do two 2x4 walls? Would be much cheaper and give a larger gap between walls for thermal break.