Masonry Paint: Introducing Silicate Mineral Paints

History of Silicate Mineral Paints

Silicate mineral paints have been developed and enhanced since the 1800’s to reach their level of success in today’s market. Originally, alchemists of the past experimented with glassy shimmering pearls found in fireplaces on their quest to manufacture gold. In 1878, Adolf Wilhelm Keim patented the name Mineral Paints by using this “water glass” technique combined with earth pigments to produce paint. This is why some people call mineral paints water glass paints. Mineral silicate paints were designed to imitate limewash but with enhanced durability. This durability has been proven as in places in Europe silicate based paint systems have lasted in excess of 100 year when applied to a lime based render substrate!

Promain are proud to supply and specify Keim paints today, giving our customers the ability to coat both their modern and heritage buildings with a product that have stood the test of time.

What Are Silicate Mineral Masonry Paints?

Silicate based paints or mineral paint do not form films on the surface. They work by absorbing into the surface then chemically binding to the underlying substrate. The paints are generally formulated with a potassium silicate binder which once applied chemically reacts the mineral substrate to form a microcrystalline silicate bond with the surface. This results in the coating becoming part of the substrate rather than forming a film. The resulting coating is highly breathable allowing the free passage of water vapour from the surface whilst at the same time being resistant against the further ingress of water into the substrate.

Keim Paints


  • Unaffected by UV Rays
  • Unaffected by Chemical Attack of Alkalis & Acid
  • Holds Same Elastomeric Qualities As Substrate
  • Long life Expectancy
  • Colourfast
  • Suitable for all types of mineral substrates


  • Expensive In Comparison to Other Masonry Paint
  • Only Available In A Limited Colour Pallet
  • You need to apply this paint directly to render. This is rather than an existing paint coating

Mineral Coatings are also immune to UV rays and chemical attack from alkalis and acid present in the atmosphere. By bonding to the substrate, the coating will also possess the same properties as the masonry below in terms of thermal expansion. They will not crack or split as the building natural expands and contracts. These benefits all translate in to long life expectancy for the coating and protection of the masonry.

Promain’s Silicate Mineral Masonry Paints

Keim Soldalit Masonry Paint

Keim have a range of high performance masonry mineral paints available through Promain including Keim Soldalit and Keim Granital. Not only targeted at heritage or period buildings, but suitable for many modern buildings also. Contractors use Keim Soldalit on prestigious buildings such as the White House in Washington DC, or the Austrian Embassy in London. These products are of a superior formulation. You can apply them directly onto existing mineral coatings or modern render without priming.

Silexcolor Masonry Mineral Paint

A more cost effective mineral coating would be the Mapei Silexcolor Mineral Silicate Paint system. Mapei Silexcolor is a highly weather resistant masonry coating that offers a further benefit of being highly vapour permeable. We can tint this paint to a large range of pastel RAL or BS colours. Furthermore, it also complies with DIN 18363.

You can apply Mapei Silexcolor both internally and externally on both cement and lime base renders. The basic system would comprise of 1 coat of Mapei Silexcolor primer followed by 2 topcoats of Mapei Silexcolor Mineral Silicate Paint allowing 12-24 hour between coats. This is highly durable masonry mineral paint system that will withstand atmospheric attack whilst remaining highly breathable and resistant to dirt pick up for many years to come.

Do you have any enquiries or questions in regards using a silicate mineral paint as your masonry paint? Contact our technical team on 01462 421333.

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