To ensure this the battens should be at least 1 2m long.
Roof tile batten gauge.
For example if the distance between the tops of the lower and upper battens is 204 inches and the maximum gauge of the tiles is 13 inches then the number of courses and strips of batten is 16 because 204 13 15 6.
So using the previous example divide your roof height of 450cms by the batten number of 14.
Holing gauge batten gauge headlap 10mm.
The result is the number of courses of tile on the roof rounded to a whole number.
The gauge is in fact the same as the margin which is the length of the tile exposed.
Not more than one in four battens should be joined over one truss for gauges over 200mm.
The batten gauge can also be calculated using the formula.
Recalculate your tile gauge based on the number of battens specified in step 7.
It also allows you to determine the holing gauge distance from hole to tail of slate and the number of linear metres of batten per m 2 of roof.
This gives 32 14cms which is the tile gauge you should use for the remaining battens to ensure correct spacing between them.
Setting out up the roof gauge set the first batten at eaves to allow the tails of the eaves course tiles to overhang the fascia by 40 to 45mm ie.
Batten gauge length of slate headlap 2.
The holing gauge can be calculated as.
Set the last batten at the ridge so that the ridge tiles will overlap the top course of tiles by at least 75mm.