North Carolina Building Contractor License Practice Exam 2026 - Free Contractor License Practice Questions and Study Guide

When installing a built-up roof (BUR), the quantity of asphalt coating required to adequately cover an area of 100 square feet generally falls around three gallons. This is due to the need for sufficient coverage that can properly seal and protect the roofing material from weather and environmental elements.

The roofing process includes applying multiple layers of felt and asphalt to create a durable and weather-resistant surface. To ensure proper adhesion and to achieve the desired thickness in the coating, the industry standard has typically settled on approximately three gallons for every 100 square feet. This amount accounts for the absorption of the materials and the need for any additional coats to achieve optimal performance and longevity of the roof.

When comparing with the other options, it's clear that the typical application rates and coverage requirements for built-up roofing systems necessitate a greater volume, which is why the other options would likely result in insufficient coverage, leaving the roof vulnerable to moisture infiltration and other issues.