Ben????? wall? Thermal bridging
gmgranteh
| Posted in Green Building Techniques on
I have a client that is interested in possibly putting strips of rigid insulation on the interior side of studs to combat thermal bridging. I know this has been discussed before but I am having trouble finding the articles. I think the name of the wall started with Ben…. I want to say benfogoli wall, but I am coming up with nothing. Is it the Ben Bogie wall?
Thanks in advance for the help.
gg
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https://www.finehomebuilding.com/membership/pdf/9750/021250059.pdf
Bonfiglioli.
So close. Thanks.
You want to take this up a notch. Furred air space assembly. We did a 9000 square foot project this way. Impressive efficiency in monitoring over subsequent years. This is a bit more than just strips, but it makes for very effective air sealing. This was a commercial project in Ontario, hence the 5/8" Type X drywall. No issues with code/inspection.
All services were run in the warm cavity. Electrical boxes mounted on their sides, affixed to the 2x3 furring strips. Pretty much zero envelope penetrations.
You may also want to check this new product out: https://www.buildwithrise.com/stories/insulated-studs
Dennis,
Often called a Mooney Wall. https://www.greenbuildingadvisor.com/question/mooney-wall-for-greater-insulation-value
One could also insulate on the warm side of the air barrier after services were run as well. Assuming the air barrier is between the stud wall and the horizontal 2x4s.
Note that if you use commercial 4" square electrical boxes instead of single gang boxes, you can then use single gang mud rings which you can rotate and mount such that the finished device in the drywall will be mounted vertically in the horizontally mounted box.
Bill
Bill, that would work too...and a great idea. We had zero issues with the sideways boxes, but ideally the ground would orient upwards as per best practice.
Tim, we used the radiant reflective vapour barrier on the inside (code required here), leaving the air gap as you would require for thermal reflectivity to be effective. Based on the CMHC research on furred air space/radiant performance, I suspect that you'd have a slightly better wall adding 3" of insulation (as you suggested), vs leaving the air space for the radiant cavity. The horizontal furring is 2x3 to give you depth for electrical boxes. Regardless, the heating efficiency on that building was pretty amazing. 9000 square feet, including a loading bay with 14 foot overhead door, with the coldest month averaging -20 C, largest bill for NG was $220 over that month.
The project was a full interior gut with exterior only touched to add a building clerestory, and solar modelled windows placed to maximise interior natural lighting.
Dennis,
Apart for being used to seeing them mounted upright, I'm not sure I wouldn't prefer horizontal outlets.
That's a nice wall, with a really well protected air/vapour barrier.