Cementitious terrazzo wearing surfaces
These are covered by BS 8204, Screeds, bases and in-situ floorings, Part 4: Cementitious terrazzo wearing surfaces code of Practice (2004).
Terrazzo comprises marble, decorative aggregates or glass aggregates bound with cement mortar (often coloured) which is ground after curing to expose the aggregate and provide a smooth hard-wearing surface. Typically the terrazzo is laid on a green cementitious screed at a thickness exceeding 15mm. To avoid cracking the following precautions should be taken:
The floor should be divided into panels no larger than 1m2
Aggregates less than 3mm in size should not be used
The water content should be kept as low as possible
The terrazzo should only be laid during suitable conditions, avoiding high temperatures and strong winds.
Slip resistance depends upon the type of finish but terrazzo can be very slippery when polished or when wet. Durability can be very good with life expectancy of up to 65 years.