2.1 Mix only as much as can be laid in one hour. Measure all quantities accurately.

2.2 Dry – mix cement, sand and/or stone chippings, adding only sufficient water to dampen the mass if materials are particularly dry. Then add flintkote as specified.

2.3 If additional water is required to assist mixing, this must be added sparingly. It is essential to ensure that the total volume of water in the mix, which includes the moisture content of the sand, is less than the volume of cement used.

2.4 When the mastic is mixed, it must be slump – free and should stand firm when sliced with a spade. Too much moisture in the mix will cause excessive shrinkage of the mastic resulting in cracks appearing in the floor.

3.1 Place screed strips of the same thickness as the depth to which the mastic is to be laid at intervals of 1.8 to 2.0 metres.

3.2 Lay the mastic between the screeds and tamp thoroughly to consolidate the mix.

3.3 Using the screed strips as a levelling guide, strike off with a straight edge working backwards and forwards in a sawlike motion. Use a wooden float to level up the surface and then lightly roll. Keep it wet and clean.

3.4 When the mastic has achieved its initial set it may be floated off with a steel trowel using an equal volume of flintkote and water as a trowelling lubricant.

3.5 Excessive use of the trowel must be avoided to prevent the fines in the mix being drawn to the surface.

4.1 When laying up to work finished the previous day, the edge of the mastic must be given a tack coat of flintkote Flooring Emulsion beforehand.

5.1 Rapid drying will cause the mastic to crack. Windows and doors should be shut to reduce draughts. At this stage the floor must not be exposed to strong sunlight.

5.2 Covering with black polythene sheet or wet sacks when the surface of the floor is no longer tacky will prevent the mastic drying too rapidly.

5.3 Under normal conditions the floor may be opened to general traffic 48 hours after curing is completed. Note: After the curing process some cracks may appear. Repair by mixing equal quantities of flintkote, cement and water, and spread over the floor using a squeegee.

Mix No.1 (for light traffic – max thickness 13mm)

• 1 volume Portland cement

• 2 volumes flintkote Flooring Emulsion

• 4 volumes sand

Mix No.2 (for Industrial floors – min thickness 13mm)

• 1 volume Portland cement

• 2 volumes flintkote Flooring Emulsion

• 2 volumes sand 4 volumes stone chippings graded mm to 3mm

7.1 The most suitable mixing equipment for making flintkote mastics are a paddleshaft or pan-type concrete mixer. Conventional rotating barrel-type concrete mixers are not as satisfactory. The mixing process is more difficult and takes longer. If mixing is done by hand, small batches are easier to handle.

8.1 Concrete or bituminous mastic floors may be patched with Mastic Mix No.1

8.2 Preparation work should be the same as for 1.4 and 1.5. Carry 100mm beyond the outer area of the edge to be treated.

8.3 Lay Mastic Mix No.1 (see 6.1) and allow for subsequent compaction by leaving the patch slightly proud of the level of the floor surface. Feather edge to the surrounding floor level to the extent of the tack coat.

9.1 Use clean sharp processed sand and clean, graded stone chips.

9.2 Do not use an all-in- mix type of material

9.3 flintkote is the binding medium in the mastic. It must not be diluted and the quantity recommended should not be altered. The cement acts principally as a filler but also adds to the hardness to the mastic floor.

9.4 Be mindful of rapid curing of the mastic in summer weather. Winter conditions and high humidity will have the opposite effect.

9.5 Clean tools and equipment daily with water when wet, Mineral Turpentine when dry.