Bostik AP 250 Flexibond Primer & Flexible Admixture 2.5L

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out of stock

Improves flexibility and tensile strength

Resistant to minor movements and vibration

Improves the deformability of C2 adhesives to meet S1 classification

White 2.5L

£17.99 ex vat
£21.59 inc vat
Work out how much you need

Using the calculator below, you can work out how much material you will need to get the job done. Please either enter your required area m2 or the width and length.

Estimated Total:

This is a rough guide calculation provided in good faith, actual usage may vary, please allow for wastage when placing your order. Pro Tiler Ltd can't be held responsible for any under ordering.

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    Coverage - As a diluted primer 2.5 litres will cover approx. 75m2 Approx. (1 part primer to 2 parts water)

                     2.5 litres of diluted AP 250 Flexibond per 20kg of adhesive

                     Approx. 0.5 litres of diluted AP 250 Flexibond per 5kg of grout

    Bostik AP 250 Flexibond is an acrylic dispersion polymer for use as a flexible admixture with cement-based tile adhesives and/or grouts. It can further be used as a primer/sealer for ready mixed tile adhesives and floor underlayment screeds.

    Bostik AP 250 improves flexibility, shear modulus and tensile strength giving greater resistance to minor movements and vibration. Cement pores are part filled with the polymer, reducing permeability and therefore reducing any damage by liquid transfer. Adhesion is enhanced when fixing to non-porous substrates and tiles. Improves the deformability of C2 adhesives to meet the requirements of class S1 according to EN12022.

    The addition of Bostik AP 250 Flexibond to a non-polymer modified adhesive or grout is required where surfaces are prone to very minor movement and vibration, or where direct fixing to glazed tiles or other impervious surfaces is required.

    Priming / Sealing:

    Do not apply neat, as skinning may occur which may cause delamination. Apply to substrate using a brush. If the surface is still absorbent, apply a second coat. Dries in approximately 1 hour.


    Ensure that all surfaces are clean, dry, sound and free from dust, grease or any contaminating barrier. Make good any unsound areas and remove flaky or peeling layers before tiling.


    Ensure that tiles are firmly fixed and adhesive is completely set. Bostik standard set adhesives should normally be left for at least 24 hours before grouting. Bostik rapid setting adhesives should be left for at least 3 to 4 hours, however, these times will be increased with sealed or impervious substrates or at low ambient temperatures, or high humidity. Ensure tiles and joints are clean, dry, sound and free from dust, grease or any contamination