Insulated Concrete Forms for Energy Savings - Page 8

 

Hi Clarence,

Yes, you are exactly right.  Are you somebody I know and have foolishly
forgotten?

--
Bert Menkveld
bertATgreentronicsDOTcom

 

Rob Dekker wrote:

around the world,

Europe.

Odd, I thought traditional scandinavian architecture was wood wood wood
(full scribed log comes to mind). I suppose you don't have many trees
left now.

A major difference between northern europe and north america
climate-wise is that the former hardly ever gets hot but there are
plenty of places in NA where it snows buckets in winter and is stinking
hot in summer.

cheers,
--mt.

 

 I am not qualified to give specs or any of the educated thoughts .But that
said in the last three years there have been four of these icf built within
a couple miles of me i have been in all of them they are quiet .in the
winter they can be heated for almost nothing.in the sumer they seem to stay
at a almost constant temp of 60 or so digrees
The most important part is the owners seem to love them.. Personally i would
never build that way.but i cant deny that the owners are very happy with
them.my 2c thanks

 

 wrote:


Well, I have yet to see one that does it right, in the sense that every
ICF system I've ever seen has insulation on both sides. A "proper"
system, IMHO, would have insulation on the outside, and either a
leave-in-place non-insulating form or a removable form on the inside.
That way, the thermal mass of the concrete is connected to the inside of
the house, and insulated from the outside - also, you don't have a bunch
of cyanide-gas-producing foam on the inside of the house if there is
ever a fire.

In practical terms, last time I went shopping, the "labor/cost saving
ICF" was $4400 before labor and concrete, while the complete job (labor,
concrete etc) with traditional forms was $5500, and I spent another $600
or so insulating just the outside, as makes best thermal sense. In total
cost the ICF was not remotely a deal.

Above ground, unless you have some issue such as being in Tornado Alley
(or having won the lottery) making it worthwhile to spend a LOT more on
your house, SIPs are a much better cost option than ICFs, while still
being very strong and very well insulated for energy savings.

Every person I know who has chosen to use ICFs has been less than
impressed with them in practice - the bracing suggestions provided by
the manufacturer should be considered to be somewhat below the bare
minimum, by their reports, and the crew has to be god-awful careful, as
they are very delicate as compared to traditional forms. Blowouts get
expensive fast...

--
Cats, coffee, chocolate...vices to live by

 


When I first saw ICF I thought the idea was great.

Now I'm not so sure it is the best approach.

From what I have been told the concrete is in contact with the ground and
since concrete is a better thermal conductor than foam, it will have a
tendency to stay near ground temperature.

Ground temperatures in the U.S. tend to be fairly stable and in the 50-60 F
range (depending on location).

This means that with ICF you have the thickness of the foam insulation on
one side of the block as insulation from a fairly constant temperature.

Another approach, which I find more appealing is Shotcrete or Solarcrete

http://www.cement.org/homes/ch_bs_shotcrete.asp

http://www.solarcrete.com/

With this approach the foam is in the center with a layer of concrete on
each side.

While I don't have any data to support the idea, intuitively this seems to
me like a better approach.  The inside layer can act as a thermal mass for
use with passive solar.

I have also been investigating the foams used for both ICF and shotcrete.  I
generally make a great effort to minimize on materials that outgas.  With
the shotcreate approach the foam is inside the wall, so I would expect less
problem with outgassing.  Better yet, some products claim to not outgas
VOC's, such as:

http://www.emegabuild.com/

There is what appears to be good information at:

http://www.greenhomebuilding.com/QandA/manufacturedQandA.htm#shotcrete

Currently I'm in the information gathering stage for our next home.  I
haven't made any decisions at this point, but I'm leaning toward finding
someone to do solarcrete or shotcrete with soy based polyurethane foam.

Steve