Hi Everyone,

I reacently had a contractor put in a slab in a house i'm building.  We didn't have the understanding or forsight to create a thermal break between the footer and the slab.  Everything else is insulated but there is about 10% of the entire surface of the slab that has direct contract with the footer.

Half of the footer will be exposed to the open air the other part will be about 8 ft below grade.  The soil is sandy and tends to hold some moister year round.

I'm concerned I'm going to have to have too much heat loss to justify  even using the system.  I have yet to buy a boiler which is giong to be the most costly part.  should I just abandon the heated floor, or is it worth it to buy it and use the heated floor even with this issue.

(I'm in Eastern Washington State near the Canadian border )

Thanks

You will of course loose a litle more heat to the footing, but It should still work. Compared to the entire surface area of the slab, it is a relatively small contact area with the concrete being a much larger mass/thickness also. I don't know that I would have run the buried tubes so close to the edge though. I have seen due to height issues, it can sometimes be difficult to add a thermal break between slab and footer.

Half of the footer will be exposed to the open air

Radiant heat or not, it would be a good idea to look at adding some external foam insulation (to the footing).

Sorry, I just added illustrated inside insulation.  The walls are ICF so the are insulated inside and out.  It's just the footer that isn't insulated.

The footing should be insulated. If this is a walk-out the insulation should extend 2-4 feet out from the footing depending on your location.

If you had experienced radiant heating you would not consider abandoning it. If this is a basement you will have to be careful not to oversize the heat source.

Professional design help would be in order.

While heating the floor causes a significant % increase in footing loss, it's a small fraction of the total heat loss. So use the radiant.