Specification of bitumen mastic

To ensure that tenders are based upon the specific grades of mastic asphalt required, it is essential that the asphalt contractor is given precise details of the BSS number and of the table and column number therein.

Natural rock aggregate mastic or limestone aggregate mastic.

The Standard applicable. The type of asphaltic cement, which is usually defined by reference to the appropriate columns in the tables of the BSS.

In addition, the asphalt contractor must be advised, as appropriate, of:

• The type of isolating membrane, eg sheathing felt, fibreglass tissue, kraft building paper underlay etc. • The material to be used fro surface reflective treatment eg , chippings, bituminous aluminium paint, acrylic coloured paint etc.

Mastic asphalt

Architects, engineers and quantity surveyors are recommended to include the following clause in their invitations to tender

Table of British Standards for mastic asphalt specifications indicating the asphaltic cement recommended in each case

* Type§ Asphaltic cement
Roofing
BSS 6925 – 988Table 3, col. 2
Tanking and Damp-proof coursing
BSS 6925 – 1097Table 3, col. 2
Flooring
BSS 1076 – grade ATable 5, col. 2
BSS 1076 – grade BTable 6, col 2
Paving
BSS 1447Table 1, col. 3