Roof Pitch
The minimum pitch is 1:5 (ca. 12 degrees). If the pitch is flatter than 1:3 (ca. 18 degrees) Katepay underlay felt K-EL 60/2200 should be used.
Application Surface / Timber Boarding
The timber used should be air-dried rough tongue and groove board or full-edged board. The surface should be smooth, dry and firm. The shingles can also easily be installed on old, un-wrinkled roofing felt.