As far as possible mastic asphalt roofs should be designed to avoid the need for maintenance, but inevitably some items of maintenance will occur.
An annual inspection of roofs is recommended and include the following.
All repair work to a mastic asphalt roof must be performed by a specialist mastic asphalt contractor. If it is necessary to remove an area, the lines of the cuts should be covered with molten asphalt until the underlying material has softened. The asphalt should not be removed until this has taken place. Under no circumstances should a hammer and chisel be used to cut cold mastic asphalt. An angle grinder may, however, be used as an alternative.
The cut edge of the existing asphalt should be softened using molten asphalt and removed to half its depth for a width of approximately 75mm. A proper lapped joint with the relaid asphalt can then be formed.