The following requirements apply in regard to thatching-

a) the thickness of the thatching shall be not less than 130 millimetres at any part of the roof, and shall consist of not less than two layers of bundles of thatching;

b) at eaves the verges, there shall be layer of bundles of thatching additional to those required in paragraph (a);

c) at valleys, hips and ridges, approved soakers shall be provided which shall be covered with a layer of bundles of thatching additional to those required by paragraph (a), and the total thickness shall be not less than 200 millimetres;

d) except as provided for in paragraph(e), the slope of the roof shall be not less than 45 degrees;

e) when a thickness of thatching double that required under paragraph (a) is provided, the slope of the roof may be reduced to 35 degrees.