Massachusetts Unrestricted Construction Supervisor License Practice Test

Is underlayment required when installing asphalt shingles on a roof with a 3:12 pitch in a 1 or 2 family dwelling?

1. No

2. Yes

3. Only for high wind areas

4. Only for low slope roofs

The correct answer is: Yes

Underlayment is an essential component in roofing, especially when installing asphalt shingles on a roof with a 3:12 pitch. This is because roofs with a pitch of 3:12 or less are considered low slope and are more susceptible to water infiltration and other moisture-related issues. The underlayment serves as an additional barrier against water and weather elements, protecting the structure beneath the shingles. In the case of a 3:12 pitched roof, building codes typically require the installation of underlayment to ensure that any water running down the roof has a secondary layer to prevent leaks. The presence of underlayment is particularly important in environments prone to rain or snow, as it adds an extra layer of protection against potential leaks that could occur if the shingles fail or are compromised. While some might think underlayment might not be necessary in certain areas or conditions, for a roof with this specific pitch in a one or two-family dwelling, following the requirement for underlayment ensures that the roof meets local building codes and performance standards.