If there is evidence of general wear and tear and you suspect the felt covering is failing
it might be time to replace the roof. However a general waterproofing treatment to the
entire surface can often give the roof a longer life. Clean the surface of the roof, using
a broom to remove loose gravel and debris.If there is evidence of moss or lichen spores,
treat the surface to a fungicide or bleach wash before commencing the repair. Use a
proprietary liquid waterproofing treatment consisting of latex rubber and bitumen that is
applied cold to the surface of the roof. Use a large brush or broom to apply the treatment
all over the roof surface.
An extra layer of open weave glass fibre will help to reinforce
the aging surface. The layer is applied while the surface is still wet from the treatment.
Bed the sections into place with the brush or broom containing the treatment. Use three
coats of the treatment on the surface, allowing each one to dry thoroughly before the next
coat is applied. Finish by covering the top coat with gravel chipping before it dries.
The
chipping compound, such as limestone, gravel or granite on top of the layers of felt,
strengthens the surface further. The idea is for the surface to reflect rather than absorb
sunlight, thus helping to protect the felt.
