Does anyone have experience with a “Thermomass” type foundation using site built forms?
Nick Furfaro| Posted inGreen Building Techniqueson
I would love to get the benefits of having the insulation in the center of my concrete foundation. I will most likely be building my own forms from 3/4″ ply and using conical ties, and can’t see a way to install the ties without drilling twice the number of holes in the foam…one set for the composite connectors and one set for the ties. Anyone have a solution to this problem, or is it even a problem? I wish the thermomass connectors had a built-in snap-tie, but I don’t think they do.
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Replies
Nick:
I would simply go right to the source. Contact Robert Long, inventor of the wall system. He knows it in and out, and is a real nice guy. His toll-free number is (866) 272-2223.
Hello Nick.
I was also considering this, and my foundation contract had done it for a local butcher, that wanted the insulation in his walls for his meat cooler. The end result worked out very well.
I think he said he used plastic spacers, that had plastic washers to hold the foam in place.
They put in 6" of foam, with 6 and 4" of concrete on each side.
I will be speaking with him in a couple weeks, and will ask for details if you still have no answer by then.
I decided to go with an exterior only foundation insulation of mineral wool.
The main draw back is you could not put a brick veneer on the building, without adding a ledger bolted through the insulation to the foundation. That would create a big thermal bridge.
If your pouring it yourself, you could also do it in two pours, putting the foam on one side, pouring the concrete, moving the form out from the foam, and pouring again to cover the foam. Big drawback is the narrow wall is not well supported while removing one half of the forms and re pouring...
Good luck.