Breathable Silicate Filler Primer - Filler by Graphenstone

Hairline cracks, crazing on old render, a smooth patch repair sitting next to rough original plaster: paint shows all of it. Filler is Graphenstone's fix. It's a white, textured silicate primer that bridges fine cracks up to 1 mm and gives the whole wall one even texture and absorbency, so your topcoat dries to a uniform finish.

It's mineral based and highly breathable, with VOCs under 1 g/l and an A1 fire classification. It works indoors and out on brick, render, concrete, lime and previously painted masonry, and one coat covers around 5 to 7 m² per litre.

Use it as the base coat under Graphenstone's mineral paints: Grafclean natural mineral emulsion, and the heritage GCS lime silicate range for interior and exterior walls. See the full Graphenstone range to choose your finish.

Application: make sure the surface is clean, dry and sound, and treat any mould or algae first. Lightly sand previously painted surfaces to give a key. Dilute with 10 to 15% water, stir well without whipping in air, then apply one even coat by brush, roller or airless sprayer. Don't go back over areas that have started to dry. Leave 24 hours before your topcoat. New mineral surfaces need at least 28 days to cure first. Outside, wait 24 hours after rain and keep the primed wall dry until it's topcoated. Not for surfaces in constant contact with water.