BPI Insulation Standards 2

Question 1

What does the term 'thermal bridging' refer to in the context of insulation?

Accepted Answer

Heat loss through conduction across a material with higher conductivity than surrounding insulation

Answer

Thermal bridging occurs when a conductive material (like a stud) bypasses insulation, creating a path for heat to transfer more readily.

Question 2

Which insulation material has the highest R-value per inch?

Accepted Answer

Closed-cell spray polyurethane foam

Answer

Closed-cell SPF provides approximately R-6 to R-7 per inch, the highest of common insulation materials.

Question 3

According to BPI standards, what is the minimum required total R-value for attic insulation in Climate Zone 5?

Accepted Answer

R-49

Answer

BPI and IECC guidelines recommend R-49 as the minimum attic insulation level for Climate Zone 5.

Question 4

What is the primary purpose of a vapor retarder when installed with insulation?

Accepted Answer

To limit moisture diffusion into the building assembly

Answer

A vapor retarder controls the diffusion of water vapor through building assemblies to prevent moisture accumulation and related damage.

Question 5

In BPI's building science framework, which metric describes the rate of heat flow through a building assembly?

Accepted Answer

U-factor

Answer

U-factor (or U-value) measures the rate of heat transfer through an assembly; it is the inverse of R-value.

(BPI) Building Performance Institute Certified Practice Test