Reduced carbon footprint pier and beam?
I’m designing an energy efficient tiny house (14’x26’ foundation, single story) in Central Texas on a zero-slope site with hard-packed gravel soils with a solid granite base at 6ft feet down. I am looking for an energy efficient foundation structure that uses minimal concrete and is cost-effective. I looked at helical piers, but cannot find a trade that will come out to our middle-of-nowhere property. Now I’m considering basic concrete pier and beam with a slip-form perimeter wall made from the copious granite fieldstone that we have on the property. This would give me the sealed crawl space I’m after while reducing the carbon footprint a bit over a solid concrete perimeter beam. I think it makes sense in our hot climate to vapor seal the ground and insulate the perimeter beam to take advantage of thermal coupling, but I cannot find much information about this approach and would love to get feedback. Is a vapor barrier helpful if I’m not below grade? Should I use closed-cell sprayfoam on the perimeter beam to seal the space or is a vented crawl space better to disperse heat? Any potential pitfalls? Thank you all so much!
GBA Detail Library
A collection of one thousand construction details organized by climate and house part