|What's it Cost?
Another question I’ve been asked many times, and one that’s been difficult to answer is
simply, “What does it cost?” A corollary to this question is “What’s better (or less
expensive) SIP’s or ICF’s?”
A friend of mine, Tom Hildreth, who runs Advanced Building and Development (www.
AdvancedBD.com), is very knowledgeable in building with scientifically proven materials
and methods to lower costs and improve energy efficiency. So, knowing his background
and experience, I put the question to him. We started making phone calls, and asking for
information from building contractors, ICF foundation contractors, concrete companies,
and SIP’s builders, gathered all the numbers, crunched them, and I think he came up with
some answers. To get an idea of costs, click here.
Now, these figures are for the Denver and the surrounding area, including the mountain
areas. The figures for the 6-1/2” SIP’s do not include freight. Freight to Colorado would
add for the average house walls and roof $0.88/sf. Tom used the Oak Ridge test data
for the R-value for the ICF’s and SIP’s. Concrete has an R–value of 0.4 per inch, so all of
the insulating properties are in the foam. The Federal Oak Ridge Report can be found at
The second page addresses the question of whether to use SIP or ICF walls. Personally,
I think if you are going to use your basement as a living space, ICF’s will out perform a
poured concrete wall by a large margin. So, unless you have some strong reason to go
with ICF’s, such as sound reduction, it appears that SIP’s are the more economical way
To see the results, click here.