A school building is being renovated with a new roof assembly. Which of the following is a requirement for the installation of a built-up roof assembly?
- AThe existing roof must be removed before the new roof is installed.
- BThe new roof must have a minimum slope of 1/4 inch per foot.
- CThe new roof must be installed over a vapor retarder.
- The new roof must be installed over a layer of insulation.
Exam tip
Always verify that the new roof assembly meets the specific code requirements for the installation method.
Why D is correct
According to Section R907.2 of the 2021 International Building Code, the new roof must be installed over a layer of insulation. Options A, B, and C are incorrect as they do not meet the code requirements.