Foundation issue resolved--kinda!

Because of the unintended deep cut for the pad, I opted to raise the house 4' by building on a crawl space. Although I am not a fan of crawl spaces, this option provided me with the opportunity to take advantage of the beautiful pastoral and mountain views at the back of the property. The foundation contractor automatically assumed that I wanted a vented crawl space--I definitely did not. There is a lot of research that shows that vented crawl spaces do not perform as intended. Here is a link to Advanced Energy's website about crawl spaces: http://www.crawlspaces.org A vented crawl space is a cheaper option and overall a bad idea. Personally, every crawl space that I have been in (in the southeast), and is at least 2 years old, I have found signs of mold and or mildew. There are two ways that I know of to do a closed crawl: 1) a sealed crawl and 2) a conditioned crawl. Because my HVAC system was already designed, I decided not to alter the design and drop a supply vent into the crawl to create a conditioned crawl. Instead I will seal the crawl floor and walls with a heavy duty poly vapor barrier and spray foam under the sub floor. Once the house is completely dried in, I plan to dehumidify the crawl space prior to laying the vapor barrier and insulating the floor. I also plan to monitor the moisture level in the crawl space to avoid potential mold and mildew issues.

As I mentioned in my first post, the original plan was to do a fully insulated slab and acid stain the concrete (as the finished floor) at the end of the project. The concrete was going to provide thermal mass to absorb the radiant heat in the winter months that would be coming through the southern facing windows using Cardinal 179 glass. Because I am now building on a crawl space, this changes the thermal mass equation. I decided to reduce the amount of southern window glazing, but still kept the Cardinal 179 glass. I also estimate that changing to a crawl space has increased the budget by about $4,000.00. Most of this additional cost is associated with substituting the stained concrete with a different flooring option. I haven't decided what the flooring will be, but as of now, I am leaning towards cork. I know someone who could help me to build earthen blocks (using clay from the job site) to serve as the finished floor, but due to time constraints and much less market appeal, I will stick with a more conventional option.