Roof Slate Headlap

Headlap is what keeps the water from penetrating through the roof.

Roof slate headlap.

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. It describes not only the means of installing slates nailing or hook fixings but also the headlaps or lap required to ensure that the roof remains watertight even at pitches as low as 20 degrees. 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.

Headlap is essen tially what renders the roof water tight. First calculate your roof pitch and then determine the inches required for sidelap and headlap. 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. 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.

Roof slope is key in determining underlayment type and installation. Tile roof institute guidelines. In slate roofing water migration is controlled primarily by the angle of the roof s slope. The primary aspects to be considered are.

If there is no headlap the roof will leak. 2 to less. 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. Two layers 30 felt 19 overlap.

Most significant is the environment with the two main factors being exposure to wind and rain. Type 90 mineral surfaced underlayment. Underlayments are installed on the roof deck prior to the installation of the slate roofing shingles. Bs 5534 2014 is the code of practice for slating and tiling.

3 12 to less than 4 12. 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. Headlap is what renders the roof water tight. Minimum recommended headlap mm unit 15 16 airfield approach business park flookburgh grange over sands cumbria la11 7ng england tel.

Lap ends 6 irc 4 2 horizontal. The steeper the slope the less water migration there will be. Headlap is what keeps the water from penetrating through the roof.