How To Work Out The Gauge On A Slate Roof

Holing gauge for holing slates.

How to work out the gauge on a slate roof.

For a 500mm long slate with a 100mm headlap the gauge is 500 100 400 2 200 so we know the gauge is 200mm. The most commonly used slate size in southern england is 500x250mm and 400x250mm in scotland and the north of england. Measurement between battens 3 2m manufacturers gauge 260mm so total recommended gauges required 12 31. The supplier of the slates should recommend the spacing up the roof between the battens known as the gauge this usually varies according to the size of the slates the pitch of the roof and the degree of exposure.

X the nail hole clearance so that a nail does not strike the top of the slate underneath. Tile batten gauge for slate. Now we can work out the holing gauge with gauge headlap x. Holing gauge mm battening gauge mm m batten per m2.

Please enter the dimensions in the white fields below and click calculate to show the results. Batten gauge length of slate headlap 2. Slate length mm battening gauge mm m batten per m2. Height of slate minus desired headlap divided by two gauge i e.

The gauge is in fact the same as the margin which is the length of the slate exposed. The best place being 3 5mm as this gives the best resistance to wind uplift so for our example we will work with 4mm although it can be as high as. This calculator will estimate the following number of slates required per square metre. Therefore if your rafter length was 4 linear meters your calculation would be 4 x 2 5 10 quantity slate half s.

Measure the distance from the top of the lowest batten to the top of the highest batten. Holing gauge batten gauge headlap 10mm. Rounded up this becomes 13 then divide this into the original measurement 246 15mm. Often you express roof pitch as the ratio between the rise and the run in the form of x 12.

Roof pitch refers to the slope which the rafter creates. The holing gauge can be calculated as. You would need 2 5 of these slate per linear metre. Total linear run of tile batten in metres.

The result is the number of courses of tile on the roof rounded to a whole number. As a guide a slate of 500 x 250 sizes uses a slate and half of 500 x 375. Finally divide the measured distance between the battens by the rounded number you now have the gauge that your roof requires.