WATER RESISTANT ADDITIVE AND BONDING AGENT FOR CEMENT SYSTEMS

Preparation
It is essential that adequate preparation is carried out prior to the application of SpECbuild BA10 modified mixes.

Ensure the complete removal of all laitance, oil, grease, moulds oil, curing compounds etc. A wire brush, bush hammer, or for large floor areas, a captive grit blasting machine may be used. Ensure that reinforcing steel is clean and free from corrosion deposits, grease or oil. When repairing spalled or damaged concrete, ensure the substrate is cut back to sound material.

Bonding Slurry
Ensure that absorbent surfaces such as concrete, brick, stone etc., are well dampened down, ensuring the surface is wet but has no free standing water.

Prepare a bonding slurry consisting of 2 parts cement to 1 part SpECbuild BA10, adjusted to a brushable, lump free consistency. Using a stiff brush, apply the bonding slurry well into the damp surface ensuring that no pinholes are visible. Do not apply bonding slurry at thickness in excess of 2mm.

It is important that SpECbuild BA10 modified mixes are applied to a wet bonding slurry. If a second coat is necessary, it must be applied after allowing the first coat to dry.

Cement
SpECbuild BA10 is compatible with all types of OPC, sulphate resisting and high alumina cements.

Mixing
SpECbuild BA10 is supplied as a one-component kit.

Mixing should preferably be carried out in a concrete mixer although hand batching is permissible where the total weight of the mix does not exceed 25 kgs.

Charge the mixer with the required quantity of sand and cement, and premix for approximately one minute. Pour in the desired quantity of SpECbuild BA10 and mix for 2 to 3 minutes. Finally, add the water little by little, until the required consistency is achieved. Due to the strong plasticising properties of SpECbuild BA10, it is best to add the water cautiously as rapid thinning can occur.

Curing
It is preferable to cure SpECbuild BA10 modified screeds as soon as they are laid to prevent rapid evaporation of water essential for hydration. This can be achieved by using polythene, damp hessian, or a suitable concrete curing membrane, such as SpECcure WE.