What is the most cost-effective way to build a cement wall in a basement and achieve a good R-value?
user-943386
| Posted in General Questions on
I have build with ICFs. It is the cost. Wondering what else is out there. Not interested in rammed earth or framing with PT materials for exterior walls
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I don't think you'll find much if the cost of ICF's is prohibitive. Maybe a poured wall w/ lots of foam outside? What do you not like about PT walls?
Wood in dirt-- It will rot someday I don't care how much chemical you inject into it. Not an option in my view
The most cost-effective insulated basement wall is probably a conventional poured concrete wall insulated on the interior with Thermax polyisocyanurate.
There are mineralic foams like shredded glas foam, perlite, expanded kiln fired clay and others which can be added to the agregate.
There are also foam developing additives available for concrete.
Contact a civil engineer to advise on the right mixture for thermal insulation and load bearing capacity.
These additives don't come cheap however.
"It will rot someday I don't care how much chemical you inject into it." Agreed, if it gets wet. However, PT walls are coated/shielded to prevent watering them, and you need to keep your soil dry w/ prevention and drainage. If you can't keep the wall dry, then go foam/concrete.
Not wanting exterior deterioration issues or a finished basement, we decided to the Thermomass system on our home recently. The layer of rigid foam is in the middle of the concrete pour. I would suspect that it's less costly than ICFs.
Concrete is one of the oldest and most widely used cost-effective construction material. These concrete walls are highly durable and have high operating energy efficiency.