Terrazzo tiles shall be formed with wet mix of white or white blended with colored cement or white cement with a color pigment added and granular terrazzo aggregates applied through out the tile to provide a monolithic finish. The tiles should be cast in strong moulds to proportion of 300 x 300 mm size with typical thickness of 19 mm with size tolerance of ± 0.5 mm.
The terrazzo tiles mix shall be proportioned and admixed with chemical to provide compressive cube strength of 3,000 psi after 28 days of curing and water absorption of less then 1.8 %. Tiles shall be cured and delivered to site without any repair grinding or polishing. After installing and grouting the tiles, grinding shall be done wet by means of a no. 800 carborundum stone.
Filling shall be carried out with neat grout of the some color, as the facing mix and this shall be worked into the surface with a wooden shaper to fill as voids and air holes. Surplus grout shall be removed with a dry cloth. After a minimum period of 24 hours, polishing shall be carried out wet by means of a No. 140 carborundum stone.
Terrazzo skirting 100 mm or 200 mm higher with chamfered top edge shall be produced in the same way as for tiles using the same mixes.
Terrazzo tiles shall be laid and bedded with adhesive tile bond premix of approved quality on concrete sub-floor (1:4 cement and sand screed, 25mm thick). All tiles shall be laid with square joints.
All tiles shall be flouted up on completed. Care being taken to fill all joints completely. The grout shall consist of neat cement of a color to match the tiling. Any surplus grout shall be cleaned of the face of the tiling and surrounding surfaces immediately and all tiling shall be carefully cleaned off.
All terrazzo surfaces shall be polished on completion. Large area such as floors shall be wet polished by means of approved machines using No. 140 carborundum wheel. Any surface too small for conventional machine polished may be polished by hand using a No. 140 carborundum stone and water. Care must be taken during any polishing operation not to be damage any angles or arises.
Terrazzo covering to items such as sills, thread and risers to steps skirting, etc shall generally be applied in accordance with the foregoing specification.