Trying to achieve a 100% Thermal break on exterior wall?

Hello
I am trying to achieve as Mike Holmes in "Holmes on Homes" would say a "100% Thermal Break"? Normally he would put in rigid foam board on the 2x6 interior studs and then build a 2x4 interior wall for Sheetrock. That gives the 100% Thermal break. What about foil? Reflectix Foil over the insulation and foil tape over the 2x6 interior studs? Cheaper than another 2x4 Wall?
See orig thread one more pics on TV bracket here
Installing a TV wall mount bracket? Anyone do this?

 

If you plan to build an interior wall, have you heard of a "Mooney Wall"?
I can get you a link if you want.
You would need to cover the studs with some foam board or another offset wall to give a true thermal break. The studs are the problem. If you've ever seen thermal imaging of a regular insulated stud wall, there's a lot of heat loss through them.

 

I think it comes down to airspace. There is a good air barrier and good insulation on each side of or in-between the wall.
Imo if you are trying to do a thermal break like suggested the 2x4s aren't all that expensive.
But that would in your case mean a slight do over!

Building a custom door jam and window sills to look right and match the rest of the house are the challenge.

The foil won't hurt.
In the space you are doing I would look into spray foam. It would almost double your r value in the walls.
I doubt it but, a small company might do the two walls, but it would probably be cost prohibited.

They do have spray foam kits in what looks like propane tanks. They do like 50 or 80 square feet I can't remember.

 

I think the smaller ones do up to 200 sq ft, but I don't know what the r-value would be at that rate. Still doesn't fix the heat loss through studs, but as long as the wall is sealed (and the foam does that quite well), I doubt Don would notice that loss much.
ETA: just took a look, and it's 200 bd ft or 16.7 cu ft., so yeah, the small one won't do a very big stud wall with any real r-value. A little over $300/kit.

 

Yeah it's been a while since I looked. When I do Projects like this, sometimes you just have to call it good enough. As long as it's up to code and current building spec or better, the best isn't always a have to have.
And to your other point of loss through the studs,
It's visually noticible in cold mornings when frost is on a house. You can see the melted outline of the studs!

 

I wish they made 2x6 studs with a Thermal break in the middle! That would save time and money. Our new garage door has a silicone gasket right down the center as a Thermal break.
Anyway the foil on the studs is thin but does reflect the heat so maybe it will keep the 2x6s from transmitting a lot of heat to the outside. We will see?

The mooney wall looks like when strapping is added to a ceiling? Good Idea - Is that why strapping is added?
Money wall
Mooney Wall -- A low cost, high R value wall

Thanks for your comments

 

Is there a paint for the studs that will get close to making a thermal break?

Funny, I might be making close to what Don is trying to achieve by accident if I ever get my basement put together. My basement is cinder block and the one wall I have completed was previously studded out but I ended up tearing out all the way to the wall and painting the cinder blocks with Watertite paint then installing rigid foam (taped at joints for air-tightness), then the stud wall (2x3 instead of 2x4 to account for the 1" foam) with R13 insulation between the studs. I did not Reflectix that wall.





The rest of my basement isn't studded out and I have put up rigid insulation with the Reflectix foil over it (ignore the sheetrock in the photo - just keeps stuff from tearing the Reflectix). I will eventually add studs and was wondering if to do R13 insulation or just place the studs sideways so there is an inch gap between the sheet rock and the Reflectix.

 

Wow - Good work Bogieb! Maybe some sort of heavy coating paint would work but it would have to reflect heat??
They sell foil backed fiberglass insulation but the higher R value Roxul combined with the polypropylene encased foil gives R27 in a 2x6 wall with much better heat retention from the reflective peoperties!

I just put up more foil tape

Wish I could do some thermal imaging on a cold day but too warm out today!

With all this foil we will be safe from toxic and dangerous E-Mag radiation! People can take off their Tin Hats and have their brain receptors be safe form all those electromagnetic fields and with no cell phone reception be safe from toxic radio waves too!

 

I'm comin' to your house Don.........gettin' real tired of wearing this tin-foil hat.

 

LOL

 

The insulation is multi-tasking

 

Not exactly what you're talking about but interesting article nonetheless. If you're in need of replacing exterior siding, perhaps you could consider a continuous thin layer of foam board under the new siding.

An ‘Insulating’ Paint Salesman Is Tripped Up By His Own Product

Using paint for insulation
Once the construction was well under way, in September 2003, King informed the builder (McCullough) that he didn’t want any insulation installed in the walls or attic. Instead, he wanted to use Super Therm paint. Although McCullough strongly advised against the idea, the homeowner insisted. McCullough said that he would only proceed with the plan if King signed a waiver absolving the builder from responsibility for any problems arising from the omission of insulation.

King directed workers to apply Super Therm paint to multiple surfaces: the underside of the roof sheathing, the roof rafters, the exposed ceiling joists in the attic, and both sides of the ceiling drywall facing the attic. The worthless paint was also applied to the interior side of the wall sheathing and the exterior side of the Sheetrock on the walls. King claimed that the Super Therm paint would provide an overall insulating value of more than R-19 for the walls and more than R-38 for the ceilings.

Since the stud bays and joist cavities of King’s home were empty, however, the actual R-value of his wall assembly was about R-2.9, while his ceilings had an R-value of only R-1.7.



Read more: An ‘Insulating’ Paint Salesman Is Tripped Up By His Own Product
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That was an, um, interesting? article. Only interesting in the manner of watching a train wreck.

 

Hey Bogieb

Are you going to do anything to make the concrete floors warmer?

That is where all my cold is coming from now. Home Depot sells plywood locking panels for a subfloor. Then you can put a finished floor or carpeting on top.
Since I move heavy stoves around, I would need a very heavy durable finished floor?

 

I have done half the basement floor with an Airgap Underlayment, then topped with plywood with linoleum on top. That system is over the damp part of the basement floor (dampness seeps up thru the floor in spots). So far it is just laying there - none of it anchored as I was unsure if it would be okay. But I must say that there hasn't been any issue with smell or anything, so it must be doing what it is supposed to do. That part of the floor stays much warmer too.

 

Hello
Got all the foil in.
This morning we turned the heat on at 7:30 AM when the workshop was 59 Deg F
At 8:00 AM after only 30 minutes, the temperature was up to 73 Degs F
Is that good?

See vids below

 

Depends... how many BTU's is the heater? What was the outside temperature? Wind? Solar gain? How long did it used to take in the past? Looks like you're doing a great job. I'm sure you'll see the results in your heating bill.

 

Stupid question time - Is there a reason you didn't cover the wood too?

 

Building Science Corporation

More info than you'll know what to do with. Foil and/or plastic isn't always a good idea though, vapor impermeable.