3 in 1 Admixture

Thompson's 3 in 1 Admixture acts as a waterproofer, retarder and plasticiser in one. It improves the workability of the mix and slows setting times, making it ideal when working on large areas.

Conforms to BS EN 934

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Waterproofer, plasticiser & retarder in one

Slow setting times

Protects against rain

Improves workability

Suitable for use in:

mortar & render 

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m2 / litre


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Add 500ml – 1L of Thompson’s 3 in 1 Admixture to the gauging water

Add gauging water according to the retardation and reduction in suction needed in the water base or key coat per 25kg of cement
- Always gauge the mix to a fairly stiff consistency

For strong backings mix 1 part Cement to 3 parts Sand
- Never apply a stronger mix over a weak backing

For weak backings mix 1 part Cement to 4 or 5 parts Sand
- Do not use mixes weaker than 1:5 for pebble dashing or harling finishes

Clean all equipment with water immediately after use