Why Use Asphalt ?

Unrivalled Versatility, Unrivalled Performance

Mastic asphalt roofing can be applied to form a continuous waterproof covering over flat, sloped or curved surfaces and can be worked around pipes , roof lights and other projections.

Mastic asphalt can be laid on most types of rigid sub-structures such as concrete, timber and metal decking. Furthermore, thermal insulation materials can be easily laid as part of a mastic asphalt roofing specification to give any required U-value. 


Mastic asphalt is also an ideal waterproofing material for extensive green roofs, intensive roof gardens and biodiversity roofs. It is completely resistant to root penetration and does not require an additional anti-root barrier.

Typical Applications

Roofing grade mastic asphalt is typically laid in two 10mm coats to a total thickness of 20mm over black sheathing felt. 

If the asphalt is be left exposed and used as a walkway, (for example to a small number of flats), then the above grades can be modified on site by adding 10% - 15% of 2mm - 3mm coarse aggregate. The first coat of normal roofing asphalt is laid 10mm thick over the BSF followed by the gritted up roofing that is now laid to a thickness of 15mm. Alternatively, on bigger jobs the 15mm thick top layer of roofing can be supplied pre-gritted. This is called 106 RD Recreational Duty Roofing.

If point loading is anticipated (e.g. on a balcony), the surface should be tiled over two 10mm coats of mastic asphalt roofing to a total thickness of 20mm over black sheathing felt. 

Trojan Asphalt contractors pride ourselves on carrying out all  mastic asphalt work to these specifications.