I have designed my long term house I hope to raise my children in.  It is an approximately 4000 sq ft daylight basement house that sits on a south facing hillside in the country.  I have been very interested in ICF for the past few years but as I get closer to construction have had some doubts as whether or not I need and can afford using ICF in the house.  My issues are:
1.  Living in the Pacific Northwest (Oregon) do I really need the added expense for insulation when we have such a mild climate here?
2.  I do not think the sound barrier properties of an ICF wall will benefit me much where my property is.

The climate here in the winters will range from the high teens at the coldest to the low 40's.  Summers will usually average low to mid 80's with a week or two that can reach 100+.  This year the summer has been very mild. 

I really like the idea of ICF but as money is a real issue in this project and my location wonder if ICF is a good option for me.  I assume the payoff is much greater in a more extreme climate.

One more question.  Since I had my plans drawn as ICF, has anyone here planned a daylight basement and had the sides that retained fill be a larger block than the ones not retaining fill.  My plans call for an 8" block on 2 1/2 sides that retain fill and switch to a 6" block on the others that have no fill against them.  Is this worth it or not?  Should I stay with 8" block if I can afford it?

Thanks,
Ryan

Well you said long term, in my opinion you will realize the savings starting immediately.

Other considerations...you live on a fault line, personally I think your better off in a concrete structure

8" vs. 6", that's the engineers call, not ours.

Other considerations...you live on a fault line, personally I think your better off in a concrete structure

I have thought about that. It is a definite consideration.
One more question: when trying to spec out a heat pump for the main floor, is there a rule of thumb to try to fit the right tonnage of system with the size and insulation value of the house. I have seen everything from a R22-R50 being quoted for the value of the walls and am trying to deal with HVAC people who are unfamiliar with ICF and how to fit the right system with what the house needs.
The basement will have radiant in the slab and a HRV unit for the whole house. Thanks

Posted By rsk on 06 Sep 2011 05:43 PM
One more question: when trying to spec out a heat pump for the main floor, is there a rule of thumb to try to fit the right tonnage of system with the size and insulation value of the house.

ABSOLUTELY!!!!

It's called use a competent HVAC contractor who will do a proper heating/cooling load calculation for you using a quality Manual J software program, like Wrightsoft Residential.

The only proper way to use a thumb in this situation is to push the space bar on the computer keyboard!

Yes, you need a very experience HVAC person for your house, too often I see the wrong size heating system being installed in ICF homes.

How you interview contractors to work on your house, you need to do the same with designers to make sure they understand ICF systems. It's not just the R value (which I think is false, actually it is real, but different) other factors such as the K value need to be applied in order to properly size the system to work efficiently.

I've had people complain to me that I sold them on an energy efficient home and now have $ 1000.00/mth heating bills...when I show up the HRV is running 24/7 on high, or a 2000 sq.ft. home with a 120,000 BTU furnace which runs for 4 minutes every 10 minutes short cycling.

Your not just buying an ICF home, your investing in a system which yes, ICF is a component, but HVAC, Windows, Roof Insulation, Insulation below the Slab, etc. etc. makes it a complete system, which when all the pieces of the puzzle are put together you will have the best we can build based on todays technology.