Plain tile fixing calculation form

For rafter pitches below 60 degrees, tiles must be fixed with 2 nails to each tile in at least every 5^th course.  At verges and abutments and at each side of hips and valleys the end tiles in every course must be fixed with 2 nails.  All tiles in the first two courses at eaves and the two top courses must be fixed with two nails.  At pitches above 60 degrees, all tiles must be fixed with two nails.

However, BS 5534 2014 requires additional nailing in some designs and locations to take account of the forces imposed by the wind.  Our technical services department can provide a full nailing specification on receipt of certain data:

Viz:   The OS map reference or postcode of the site.
        Height to the ridge.
        Roof pitch
        Building width and length.
        Town or country location