Slate Tile Roof Pitch

In order to provide you with the opportunity to specify low pitched slate roofs below 20 with confidence siga commissioned the bre to carry out a set of tests.

Slate tile roof pitch.

In areas with high winds the underlayment must be attached with corrosion resistant fasteners according to manufacturer s instructions. Higher exposure or different sized slates necessitated a greater roof pitch of 22 5 or more. Most commonly a roof pitch will be from 0 flat to 12 45. The pitch of a roof is determined by 2 numbers.

Slate tile requires a pitch of 4 12 or greater. Additionally if the climate can cause backups of water as ice under the eaves the tile requires at least two layers of underlayment cemented together. The rise and the length. For tile shingle slate and metal roofing.

Generally speaking 20 degrees 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. Conventional low pitch slate roofs are recommended down to a minimum of 20 in areas of sheltered or moderate exposure providing a 500x300mm slate is used and a headlap of 115mm. When slating with a shallow pitch a wide slate is highly recommended for maximum side lap or lateral lap side overlaps.