Roof Slate Headlap

When the head of a slate is overlapped by the slate two courses above it that s called headlap that s the critical overlap on a slate roof figure 2.

Roof slate headlap.

Underlayments are installed on the roof deck prior to the installation of the slate roofing shingles. Headlap is what renders the roof water tight. When the head of a slate is overlapped by the slate two courses above it that s called headlap that s the critical overlap on a slate roof figure 2. When slating with a shallow pitch a wide slate is highly recommended for maximum side lap or lateral lap side overlaps.

If there is no headlap the roof will leak. Minimum headlap for fixing slates with nails or hooks the installation of a slate roof involves a number of aspects that must be considered in the design process. Lap ends 6 irc 4 2 horizontal. Headlap is what keeps the water from penetrating through the roof.

Roof slope is key in determining underlayment type and installation. Type 90 mineral surfaced underlayment. Tile roof institute guidelines. The primary aspects to be considered are.

According to an identification guide on the slate roof central website some of the hardest heartiest types are purple slate non fading green slate and grayish black buckingham slate which can. First calculate your roof pitch and then determine the inches required for sidelap and headlap. 30 felt or comparable evaluation report required. Headlap is essen tially what renders the roof water tight.

Most significant is the environment with the two main factors being exposure to wind and rain. 3 12 to less than 4 12. Bs 5534 2014 is the code of practice for slating and tiling. 2 to less.

Minimum recommended headlap mm unit 15 16 airfield approach business park flookburgh grange over sands cumbria la11 7ng england tel. The steeper the slope the less water migration there will be. If there is no headlap the roof will leak. Slates must overlap 3 inches on the side which is called sidelap and must overlap on the top which is called headlap.

Generally speaking 20degrees is the lowest advisable pitch for a slate roof depending on the size of the slates and how much that the roof is exposed to moderate weather conditions. In slate roofing water migration is controlled primarily by the angle of the roof s slope. Headlap is what keeps the water from penetrating through the roof.