
Earthborn Bonding Primer is a water-based, eco-friendly primer designed to improve paint adhesion and balance surface absorbency. Suitable for both interior and exterior use, it provides a reliable base for Earthborn Claypaint and Silicate Masonry Paint, helping to achieve a smooth, consistent and long-lasting finish.
Ensure all surfaces are sound, clean, dry and free from grease, dust, wax or other contaminants.
Always carry out a small test area before starting to confirm compatibility, adhesion and final finish with the chosen top coat.
Once fully dry, the primed surface can be finished with Earthborn Claypaint or Silicate Masonry Paint to achieve a durable, breathable coating.
It promotes strong adhesion and evens out differing levels of surface absorbency, creating a reliable base for a consistent finish under Earthborn Claypaint (interior) or Silicate Masonry Paint (exterior). It's water-based, low odour and suitable for both interior and exterior use.
Earthborn Bonding Primer can be used on sound, stable, previously painted substrates and poorly absorbent surfaces such as engineered brickwork, plaster and gypsum plasterboard. It also supports uncured lime plaster internally, evening out absorbency before applying Claypaint.
Do not use on fresh, highly absorbent mineral surfaces such as new lime plaster, or on synthetic resin renders, latex paints, plastic, wood, metal or glass. Avoid water-repellent areas and surfaces affected by rising damp or salts until they are treated.
Coverage is approximately 4-7m² per litre. It is touch dry in around 1 hour and ready to recoat after 4-6 hours under normal conditions (20°C, 65% humidity). Drying times may vary depending on temperature and airflow.
Stir thoroughly before use. Apply thin, even coats with a brush, roller or spray, keeping a wet edge to prevent lap marks. For very absorbent surfaces, thin with up to 5% clean water. Only apply when temperatures are above 8°C and avoid direct sunlight, rain or cold weather during drying.
Yes. Earthborn Bonding Primer can be sprayed using airless equipment. Typical settings are around 120 bar with a 0.58mm (523 tip) nozzle and an appropriate filter. Always test a small area first to confirm flow, pattern and finish.
Yes. It offers medium breathability with an Sd value of 0.35m and contains only trace VOCs (<0.1%), making it a healthier, eco-friendly choice for homes and heritage properties.
Surfaces must be clean, dry and free from grease, dust and flaking paint. Treat mould or mildew with a suitable cleaner and allow to dry. Lightly sand glossy or previously painted surfaces to provide a key. Paints applied before 1960 may contain lead - seek professional advice and follow safety precautions when sanding or stripping these coatings.
Clean brushes and rollers with warm, soapy water immediately after use. Store any remaining primer in its original, tightly sealed container in a cool, frost-free place. Do not pour leftovers down the drain - allow them to dry and dispose of in accordance with local regulations.