[Greenbuilding] Conditioned Crawlspace Ventilation

[Ken Beiser]

I am also designing a final addition to our home.  I planned on part of the 
room having a wood floor covering and part tile or other stone.  I have a 
zone already reserved in my system for in- floor hydroninc heat.  I was 
considering a gypcrete or concrete pour on the subfloor or using Warmboard 
as the subfloor.  I had planned to insulate the floor and have an 
unconditioned crawl space.  I also planned to extend my HRV system to this 
wing and it is sized for the addition.

I am a timber framer and did the "easy part" already and have the heavy 
timber frame in storage.  I have some salvaged SIPs for the roof and 
originally planned the walls to be straw bale on a wood framed canteleverd 
floor over a crawl space.  I do not plan to do straw bale at this time, 
mostly due to the chance of it "lowering my resale" value.  I may do a 
staggered stud wall system with cellulose.

I was interested in the proposal to just fill in the perimeter walls and 
pour some sort of slab instead of having a crawl space and framed floor. 
Does this sound like a better approach?  It may be a better way for moisture 
control, too.  Could I eliminate a foundation drain and waterproofing?  I 
would be willing to try an earth floor, too.

Any and all input would be appreciated.

Ken
Whitefish, MT