Most forms of solid construction will provide a suitable base for Permanite flooring asphalts.
Concrete surfaces, free from cracks or indentation, provide an excellent base for the application of flooring asphalt. They should be designed and constructed in accordance with the recommendations in BS 8204: Part 1. In the case of uneven concrete a levelling coat of asphalt or sand cement screed may be necessary.
CONCRETE BEAMS AND HOLLOW TILES
Where the base on which the flooring asphalt is to be laid is of precast concrete beams, hollow beams or hollow tiles, a sand and cement screed designed in accordance with BS 8204: Part 1 may be required.
STONE FLAGS, QUARRY TILES OR BRICK FLOORS
Old floors of these types can form a good base to receive asphalt flooring. However, it may be necessary to provide a levelling coat of asphalt to take up irregularities in the surface.
Asphalt can be laid over timber boarded floors providing the structure is free from deflection. Minor deflection can be catered for by the inclusion of a 10mm cushion coat of roofing or tanking asphalt. In all cases a separating membrane of black sheathing felt is required.
A thin coat of bituminous primer must be applied by the asphalter after the surface has been prepared. The asphalt is laid direct without the use of a separating membrane and to compensate for deflection a 10mm roofing or tanking layer should be specified as a cushion coat