I thought this was covered once but a search bared no fruit.
Is there a way to achieve a 100% thermal break at a moment frame / clerestory windows and other store front assembles?
Other than wrapping the tube steel with foam and or burring it in framing which is not called for how can a thermal break be achieved and have exposed TS on the interior? This is in a hot arid climate.
Thanks
Wood Guy
Jan 6, 20 9:48 am
I'm not sure what "exposed TS" is. This may sound simplistic, but to create a thermal break, you need an insulating material between the steel and the outdoors. There is not a specific R-value or thickness of insulation required to meet the definition of the thermal break; in a hot climate just R-5 or R-10 would probably be enough.
Everyday Architect
Jan 6, 20 11:47 am
Exposed TS = exposed tube steel?
Wood Guy
Jan 6, 20 12:28 pm
Doh, of course, thanks. That leads to my tube steel rant--of course architects prefer its clean look to that of W section or other most industrial-looking shapes. But tube steel is usually produced using basic oxygen furnaces, which run on coal and are heavy polluters and greenhouse gas producers. W-sections and similar shapes in the US are usually made using electric arc furnaces, which run on electricity and produce steel products with much less upfront carbon emissions. Plus tube steel is not an efficient use of material, compared to wide-flange shapes which place material where it will do the most good.
Non Sequitur
Jan 6, 20 12:36 pm
^ I prefer W and C sections over HSS. Do I get a cookie?
Wood Guy
Jan 6, 20 1:51 pm
You're unusual among architects, NS. You get a cookie.
OddArchitect
Jan 6, 20 1:58 pm
Make sure it's a Canadian cookie though.
Non Sequitur
Jan 6, 20 2:00 pm
Maple flavoured.
Non Sequitur
Jan 6, 20 10:00 am
At first, I thought this was another Jawknee post... but then I realized that all the words in the title were english and made decent sense.
Hot & Arid is 100% not my climate, but we have had to deal with thermal bridging in large structural members before (2' to 3' perimeter HSS members). I find it rather impossible to split the structural member to add a thermal break, but our solution was to fill the steel tubes with spray-foam for a considerable length beyond where a TB would be placed. The steel will sweat tho...
Wood Guy
Jan 6, 20 10:50 am
The foam fill is probably more to avoid internal condensation than to provide energy efficiency, right? At R-0.003 (U-322), A992 steel is about 400 times more conductive of heat than framing lumber (R-1.2, U-0.8). It takes 33 feet of steel to equal the thermal resistance in one inch of wood. Or 160 feet to equal an inch of foam.
Non Sequitur
Jan 6, 20 10:57 am
^correct, we had many issues with steel sweating since we work with -40C to +40C temperatures. Depending on OP's design, a hunk of nice finished lumber might be OK. You don't typically see TB in timber framing.
Everyday Architect
Jan 6, 20 11:20 am
NS, do you have access to Tnemec's Aerolon up in the great white north? We've had some good success using it to help prevent the sweating you're talking about. It's not appropriate for every situation, but might help in some of them. Don't believe the marketing hype though, it's not a thermal break. It's simply an insulating coating.
Non Sequitur
Jan 6, 20 11:46 am
Yeah, I would not believe a TB can be achieved with a film. Product looks interesting but I don't think it passes all of our ULC regulations since I can't find much about it, but it passes our fire reqs, so it's probably out here.
Everyday Architect
Jan 6, 20 1:15 pm
It is fun watching the Tnemec representatives' gears churning when I've questioned them on why they call this a thermal break (heat is still transferring through the steel unabated). I only use it when I'm trying to keep the surface temp from dropping below the interior dew point to prevent condensation on the steel. For that, I think it is a remarkable product.
Miles Jaffe
Jan 6, 20 10:57 am
It's a full custom build with armatherm or some other break material.
OddArchitect
Jan 6, 20 11:07 am
It's like Miles said, you have to crate two separate pieces of your steel frame and use a thermal brake product.
We've used this product in western Colorado (temp range 5F to 110F) with great success. It's a structural plastic.
Neat product. Never seen this before but it looks like it was just recently approved in Canada (august 2019).
OddArchitect
Jan 6, 20 11:42 am
Yeah the stuff is rather cool - structural thermal brake plastic! I'm such a geeky dork to be excited about this.
Everyday Architect
Jan 6, 20 11:50 am
We've used Fabreeka's product in the past. I recently came across the Armatherm products Miles mentioned and I'm waiting for the next opportunity to discuss with a project's structural engineer to see if they have a preference for one or the other. They both look comparable from my cursory glance.
OddArchitect
Jan 6, 20 12:19 pm
Good to know. Thanks EA!
atelier nobody
Jan 6, 20 3:18 pm
Used it under every column baseplate on a project in Antarctica, as well as vertically separating steel frame from exterior wall and roof assemblies. Somewhat creatively, also put it under door thresholds to prevent bridging from exterior to interior concrete.
I thought this was covered once but a search bared no fruit.
Is there a way to achieve a 100% thermal break at a moment frame / clerestory windows and other store front assembles?
Other than wrapping the tube steel with foam and or burring it in framing which is not called for how can a thermal break be achieved and have exposed TS on the interior? This is in a hot arid climate.
Thanks
I'm not sure what "exposed TS" is. This may sound simplistic, but to create a thermal break, you need an insulating material between the steel and the outdoors. There is not a specific R-value or thickness of insulation required to meet the definition of the thermal break; in a hot climate just R-5 or R-10 would probably be enough.
Exposed TS = exposed tube steel?
Doh, of course, thanks. That leads to my tube steel rant--of course architects prefer its clean look to that of W section or other most industrial-looking shapes. But tube steel is usually produced using basic oxygen furnaces, which run on coal and are heavy polluters and greenhouse gas producers. W-sections and similar shapes in the US are usually made using electric arc furnaces, which run on electricity and produce steel products with much less upfront carbon emissions. Plus tube steel is not an efficient use of material, compared to wide-flange shapes which place material where it will do the most good.
^ I prefer W and C sections over HSS. Do I get a cookie?
You're unusual among architects, NS. You get a cookie.
Make sure it's a Canadian cookie though.
Maple flavoured.
At first, I thought this was another Jawknee post... but then I realized that all the words in the title were english and made decent sense.
Hot & Arid is 100% not my climate, but we have had to deal with thermal bridging in large structural members before (2' to 3' perimeter HSS members). I find it rather impossible to split the structural member to add a thermal break, but our solution was to fill the steel tubes with spray-foam for a considerable length beyond where a TB would be placed. The steel will sweat tho...
The foam fill is probably more to avoid internal condensation than to provide energy efficiency, right? At R-0.003 (U-322), A992 steel is about 400 times more conductive of heat than framing lumber (R-1.2, U-0.8). It takes 33 feet of steel to equal the thermal resistance in one inch of wood. Or 160 feet to equal an inch of foam.
^correct, we had many issues with steel sweating since we work with -40C to +40C temperatures. Depending on OP's design, a hunk of nice finished lumber might be OK. You don't typically see TB in timber framing.
NS, do you have access to Tnemec's Aerolon up in the great white north? We've had some good success using it to help prevent the sweating you're talking about. It's not appropriate for every situation, but might help in some of them. Don't believe the marketing hype though, it's not a thermal break. It's simply an insulating coating.
Yeah, I would not believe a TB can be achieved with a film. Product looks interesting but I don't think it passes all of our ULC regulations since I can't find much about it, but it passes our fire reqs, so it's probably out here.
It is fun watching the Tnemec representatives' gears churning when I've questioned them on why they call this a thermal break (heat is still transferring through the steel unabated). I only use it when I'm trying to keep the surface temp from dropping below the interior dew point to prevent condensation on the steel. For that, I think it is a remarkable product.
It's a full custom build with armatherm or some other break material.
It's like Miles said, you have to crate two separate pieces of your steel frame and use a thermal brake product.
We've used this product in western Colorado (temp range 5F to 110F) with great success. It's a structural plastic.
Fabreeka.
https://www.fabreeka.com/products/#category-48
Neat product. Never seen this before but it looks like it was just recently approved in Canada (august 2019).
Yeah the stuff is rather cool - structural thermal brake plastic! I'm such a geeky dork to be excited about this.
We've used Fabreeka's product in the past. I recently came across the Armatherm products Miles mentioned and I'm waiting for the next opportunity to discuss with a project's structural engineer to see if they have a preference for one or the other. They both look comparable from my cursory glance.
Good to know. Thanks EA!
Used it under every column baseplate on a project in Antarctica, as well as vertically separating steel frame from exterior wall and roof assemblies. Somewhat creatively, also put it under door thresholds to prevent bridging from exterior to interior concrete.
Generic details and (at the end) more products:
https://www.aisc.org/globalassets/modern-steel/archives/2018/09/breakingupisnthardtodo.pdf
^ Good article. Saved for later.
learned new stuff, thx peeps