Can be either
• sewn
• tied
or
• screw-fixed.
Roof pitch ≥ 45°
with a
depth of
d = 1.5 x 30 cm
at the ridge
Height above ridge ≥ 0.8 m
(FeuVO)
can be made of heather, sods, reed,
copper or clay (Netherlands)
≥ 40°
to valleys,
≥ 0.6 m from the indent