Installation
What is Headlap?
Roofing Glossary · Installation
Definition
The distance each shingle course overlaps the top of the course two rows below it, creating a double or triple layer of protection across most of the roof surface. Standard headlap for 3-tab shingles is 2 inches. Architectural shingles achieve headlap through their laminated construction. Insufficient headlap reduces weather resistance and typically voids manufacturer warranties.
Related Roofing Terms
→
ExposureThe portion of each shingle that is exposed to weather, measured from the lower edge of one shingle ...
→Starter CourseThe first row of shingles or starter strip material installed along the eave and rake edges of a roo...
→Asphalt ShinglesThe most widely installed residential roofing material in North America, consisting of a fiberglass ...
More Installation Terms
Get an Instant Roof Estimate
Now that you know what headlap means, put that knowledge to work. Enter your address to get a free satellite-based estimate and compare standardized quotes from pre-vetted local contractors.
Get My Free Estimate