This is how i ve worked out the formulae.
How to felt a hexagonal roof.
Hexagonal butt bitumen felt roof shingles from leading brands including roofing superstore iko and katepal our hexagonal shingles are available in a wide choice of felt colours and finishes and can be used as shed felt tiles roof felt tiles or as felt tiles for other outbuildings and projects.
Roofing felt comes in rolls that feature pre marked lines 2 to 3 inches from the top and bottom edges.
The rest of the roof was fairly standard dpc plywood roofing felt then asphalt shingles.
Felt roof ridge measure the distance between the final courses of shingles on either side of the roof in order to ensure that there will be sufficient overlap of the ridge detailing membrane.
The finishing brass finial was cobbled together from a doorknob and the base of a discarded brass vase.
Unroll the felt so that the lines are facing upward.
We have found the value of a which defines a point on the underside of the triangular panel directly under the roof s apex we know that when 2 planks meet at some angle the bevel will be the same right along the edge.
I used a plant pot to cover the finial and then felted it over.
I positioned the cross members to coincide with the plywood roofing pieces.