I am starting a house with walkout basement and cannot find a detail of a thermal break at the door sill. Can anyone point me in the right direction or give some kind of detail. Thank you. Brian

On the past several jobs, I have cut the ICF form on the outside wall to the height of the finish floor slab, cut the inner wall of ICF 4" lower. I keep the ICF wall pour from filling that space and instead let the floor pour fill it later. Install a board across the outside of the opening for a screed and cut some scallops out of the foam to get the concrete to flow within 1/2" of the outside surface and give better bearing to the door sill.
There will be more heat loss there than through the surrounding ICF wall, but it's a small area.
I would still like to hear of a better plan than that, though. I'm sure it can be improved.
rgb

Thanks for that response. For some reason I kept thinking the foam should be kept on the inside of the wall. Your description sounds perfect.

If you are setting your doors to the inside, keep the inside of the block higher then create a sill on the exterior side, if going to the outside keep the outside higher and use a thin stone sill or something similar on the outside.

Here's the way I did my doorways. Three pics in this msg, three in next.

The first pic shows the garage door. The 3/4" blue board is set to the inside to come in under the door. It extends downward into the gravel base about 2" or more. I cut both foams of the ICF about 4" below finish surface. The sill is flush to the outside of the ICF because the driveway slab comes right next to it.

The second pic shows the form setup for the garage man door. The 3/4" blue board is aligned with  the inner side of the inside foam. This puts the foam thermal break right under the aluminum door threshold. The threshold has a built in thermal break. The sill extends to the outside of the ICF about 1 1/2" and down over the dimple membrane.

The third pic shows the concrete at the garage man door and the garage/kitchen doorway. Note the wood form on the kitchen side of the garage/kitchen doorway. You'll see in the next set of pics the gap between the concrete and subfloor.

Here the first pic shows the garage/kitchen doorway after the form piece was removed. The yellow foam you see filled in the void between the form and the top of the roughly cut ICF. That gap was then filled in with a wood strip and a strip of blue board.

The second and third pics show the front door sill. You can see the wood filler strip in the third pic. The blue board is between it and the concrete and is level with the top with the concrete. All my doors are set to the inside of the ICF wall and the thermal break is positioned to be under the door threshold. The garage man door is probably the one that most closely matches what you will be working with, i.e., concrete slab inside, a doorway sill, and concrete slab or walk outside.

Hope this gives you some idea of what to do. I am by no means saying my way is the best way, but in my mind it nicely solves, or mitigates, the problem of thermal conductivity from outside to inside at the the door. I plan to coat the concrete sill with an epoxy type of colored and sanded concrete coating.

We have been using 3 1/2" water pump discharge hose now for about five years, we place this at the point that is directly below where the sill will be placed and pour the slab up to it on both sides inside first. This acts as an expansion joint as well as a thermal break and when the garage door or the sill of a walkin door are placed on it seals very well.
We have had one of these get damaged in a manufactureing plant when the forklift driver ripped it open the fix was as simple as pulkling it out and squeezing the new hose back in. The concrete forms a nice c-channel for that pupose, being a rubber product it has a very long life span and it is covered the majority of the time.
I will try and send a detail on this .

Hi, I am in the process of building a large garage in northern WI and will be installing in floor hydronic heat. I will have 2" on foam under the floor and 1" of foam as thermal break between the slab and the walls.

My question is... What is the best way to install the thermal break at each of the garage doors. The mason has poured the 4' frost wall and left roughly a 6" deep opening at each of the garage doors so that he can pouring the threashold at the same time as the floor is poured. I know I need a thermal break somewhere... Does anyone have a suggestion for the best energy efficient and yet asthetic and functional approach?

I know he is planning on a black expansion joint between the door threashold and the apron, but my guess is that this would still allow significant heat loss at each door apron...

I need your help and suggestions!!!

Posted By DJFlak on 05 Jun 2010 08:47 PM

My question is... What is the best way to install the thermal break at each of the garage doors. The mason has poured the 4' frost wall and left roughly a 6" deep opening at each of the garage doors so that he can pouring the threashold at the same time as the floor is poured. I know I need a thermal break somewhere... Does anyone have a suggestion for the best energy efficient and yet asthetic and functional approach?

I would take a hard look at what Cattail bill suggests in the post above. I would have done that myself but I couldn't find the appropriate hose locally, hence the 3/4" blue board you see in the attached photo above - garage door sill.jpg. The only real problem I've encountered with the foam is a lot of it melted when I put concrete sealer on the floor. It slopped onto the foam and melted it good. My floor isn't heated so I figured 3/4" was sufficient.

You may want to use 2" foam and cover the exposed edge with a good pourable concrete crack sealer. If you locate the break just right it'll be under the door edge so looks shouldn't be a great concern.

This is a subject I did not find a lot of info on when I confronted it over 2 years ago.

Posted By DJFlak on 05 Jun 2010 08:47 PM
Hi, I am in the process of building a large garage in northern WI and will be installing in floor hydronic heat. I will have 2" on foam under the floor and 1" of foam as thermal break between the slab and the walls.

cap top off of 1" thermal break with PT to protect edge

Another idea to make the thermal break is to get a white vinyl 3 rail fence rail, 1.5" x 5.5", and rip it down on a table saw to the desired height of the concrete.  Turn it so the cut side is downward.

http://www.valleyfence.net/vfpics/3...l%2015.jpg

arkie6;

thats a great idea , got me thinking a piece of 1-1/4" composite decking would work too

Posted By arkie6 on 08 Jun 2010 02:32 PM
Another idea to make the thermal break is to get a white vinyl 3 rail fence rail,

Man, wish I would have thought of that, or had someone else mention it, when I was doing my garage. The sides may collapse some from the weight of the concrete but I don't think it would enough to worry about. Gives you the best break there is, a void between two thermal surfaces.

Posted By cmkavala on 08 Jun 2010 04:13 PM
arkie6;

thats a great idea , got me thinking a piece of 1-1/4" composite decking would work too

Thermal conductance would be an issue. According to one chart I find it's about 3x that of wood!

Posted By dmaceld on 08 Jun 2010 04:23 PM

Posted By arkie6 on 08 Jun 2010 02:32 PM
Another idea to make the thermal break is to get a white vinyl 3 rail fence rail,

Man, wish I would have thought of that, or had someone else mention it, when I was doing my garage. The sides may collapse some from the weight of the concrete but I don't think it would enough to worry about. Gives you the best break there is, a void between two thermal surfaces.

You could rip some strips of 1" foam board to the inside width of the rail to help it hold its shape during the pour.

Another thing about these vinyl fence rails - they have two internal ribs that cross from side to side so that they divide the 5.5" long section into thirds (at least the ones that I looked at at Lowes had them). Those ribs would keep the sides of the rail from collapsing from the concrete pour.

One more thing is that the local Lowes only carries 8' long rails (I haven't asked, but you might be able to special order the 16' long vinyl fence rails). I do know that the local commercial fence building place has the 16' long rails in stock as I have seen them from the road. These 16' long rails would be better suited for garage doors >8' wide so that you have one continuous piece that could be cut to the desired length.

You also would want to solidly plug the ends to keep water from rain, snow, washing the floor, etc., from getting inside. The water would seriously compromise the insulation value of the open space.

Nice ideas guys. Now here is a related difficult question: I am bidding a home with main and second level Lite Deck floors with cantilevered decks. The interior floors will be radiant heat, but how can I address a thermal break when the reinforcement needs to be near the top of the slab?

Posted By rvalue on 16 Jun 2010 09:35 AM
Nice ideas guys. Now here is a related difficult question: I am bidding a home with main and second level Lite Deck floors with cantilevered decks. The interior floors will be radiant heat, but how can I address a thermal break when the reinforcement needs to be near the top of the slab?

I don't think you can, you should pose the question to the architect to see what they had in mind?

If I understand your problem corectly I think you'll need something like this:

http://www.halfenusa.com/pdfs/Balconies-White%20Paper.pdf

there are a lot of other similar systems available. just google "balcony thermal break" and youll find them

good luck
Adi