The flash and fill style of Insulation is a standard way of insulating homes across the country. It is a hybrid form of insulation because it is a combination of 2 types of insulation. Two pound closed cell spray foam is sprayed against the inside of the sheathing in various depths from 0.25” inch to 3” deep then the remaining chamber area is filled with a blown in insulation as show in the main illustration. The EcoSmart™ Stud upgrade picture below shows how the EcoSmart™ Stud interacts with and improves this hybrid insulation style.

Layer one the 2 lb. closed cell spray foam spreads through the EcoSmart Studs at points A & B rather than being stopped by a solid stud. This accomplishes two things. Thermal breaks and it completely embeds the EcoSmart™ Studs in the spray foam which is 100% attached to the sheathing. Even with just point A filled with spray foam the PLF rating is above the racking requirements for most high wind and seismic areas with just a hybrid 6/12 nailing pattern and 7/16 OSB.

The depth and the mix of the 2 insulation’s and which EcoSmart™ Stud is used will determine the U-value or effective R-value of the assembly. With the 2×6 EcoSmart™ Stud and the 1” minimum 2 lb. spray foam required for the installation the effective insulation value of the exterior wall assembly will meet the U-Value requirement for the 2021/2024 Energy Code. The wall assembly is also sealed tight against air infiltration along the entire the length of the exterior walls for the building including the corners.

The 2×8 EcoSmart™ Stud has all the same structural benefits of having the sheathing glued and nailed to the framing.  With the extra depth for insulation the U-value and effective R-value for any insulation mix of 2 lb. spray foam and blown in insulation far exceed the requirements for the 2021/2024 Energy code.

See our resources tab for installation instructions, TER link, and for the downloadable PDF for Energy Design Criteria of exterior walls.  There is also a blog post going over this information for Energy Star Zero Energy Ready Homes.