Winter foundation pouring:
I asked our PM about what they do differently when they pour a foundation in winter and here is what he said:
Typically our foundation wall mix is a 3000 PSI concrete with no calcium. Today we will be using a 4000 PSI mix with type 3 cement and 1.5% liquid calcium. The type 3 cement is the key element. Type 3 cement has a higher cement ratio than our normal wall mix and it will allow the wall to set up and not freeze and the 4000 PSI is a much stronger strength than the normal 3000 PSI. Also the poured wall company will be covering the top of wall with insulated blankets to keep the heat in.
In the past couple of years Ryan Homes started to improve their basement waterproofing and now instead of putting tar on the foundation walls, they are using a material called GeoMat by Mar-Flex. I was told that the tar would eventually crack and wouldn't provide much of a long-term waterproofing solution. One of the pictures below is a close-up of the GeoMat and here is what I found on the product:
Mar-flex Geo-Mat rolls are made of high density polyethylene (HDPE) which offers strong resistance to hydrostatic pressure and provide excellent drainage. Mar-flex Geo-Mat rolls feature dimples that are aligned along vertical and horizontal axis to rapidly channel water from grade to the footer drainage system.
Next week they deliver the wood and hopefully start framing!
Quick note: I'm not sure if we lucked out but our PM is great to work with. I'm not sure I would feel good about this process if we didn't trust him as much as we do and I'd suggest anyone looking to build a RH to ask to meet the PM before you build.