Sub freezing temps and shop supplies

Just south of was so cold here it was 12 at midnight. tired ol d joke. Am seeing a new house go up and the insulation work is pretty inter esting. Single level home on a 3 ft crawlspace. Spray foam on the walls of the crawlspace, plastic over the dirt, nothing underneath the flooring. Ins ide walls and inside of roof all sprayed, all wiring, plumbing holes in flo or and wall foamed. Insulation guy says they don't need insulation over the ceiling and under the floor because any outside temp change is accounted f or underneath the roof and on the walls of the crawlspace. I guess time wil l tell but that is a long way from fiberglass or rockwool in the attic and under the floor. I know it is a lot more expensive initially but supposed t o recoup through lower energy bills.
Add pictures here
<% if( /^image/.test(type) ){ %>
<% } %>
Add image file
Upload is a website for homeowners and building and maintenance pros. It is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.