NBS Source


Suitable for use on unpainted surfaces.


A complete range of products for the cleaning, consolidation, repair and preservation of natural stone.

Owing to the specialist nature of these products and the highly sensitive areas of their application, advice and dedicated project specifications should be sought from Keim Mineral Paints Limited prior to undertaking stone repairs.

System components:

– Stone cleaning:

Keim Steinreiniger N: A neutral, environmentally harmless, biodegradable cleaner suitable for the mild and gentle cleaning of natural stone.

– Stone consolidation:

Keim Silex OH is an ethyl silicate consolidation system for natural stone. Suitable for surfaces where the substrate has become unstable and a deep surface penetration is required to strengthen embrittled surfaces. Can be over coated.

– Restoration mortars:

  • Keim Restauro Grund: A pre-mixed, dry bagged mineral ground restoration mortar (grey colour only).
  • Keim Restauro Top: A pre-mixed, dry bagged mineral finishing restoration mortar (available in lightfast stone shades, consult manufacturer).
  • Keim Restauro Fuge: A mineral, dry bagged pre-mixed restoration mortar with hydraulic binders for joint replacement.

– Treatment/ Decoration:

  • Keim Lotexan N: A siloxane based clear water repellent treatment for use on weathered natural stone.
  • Keim Restauro Lasur: A water repellent low pigmentation silicate colour wash for use on mineral substrates.

The system is available in standard shades from the Naturstein colour range, as well as colour matches and bespoke colours.

Surface preparation:

  • All gaps, cracks and holes in the substrate must be filled prior to any treatment. Any new/ repaired surfaces should be left for a minimum of 15 days prior to any treatment taking place.
  • All surfaces must be thoroughly washed down with clean cold water to remove all surface dirt and dust. Ensure all surfaces are clean, sound, wind dry, dust free and free from all surface contaminants.
  • All loose, flaking and unstable material must be identified and then thoroughly removed using stiff brushes and broad bladed scrapers to get back to a sound edge; these edges should then be feathered in. Ensure that any paint materials left remaining and the underlying substrate is sound and adhering well. Any gloss or shiny surfaces should be thoroughly flatted down using sand or emery paper to create a good key.
  • Any algae growth should be wire brushed to remove all growths and treated with Keim Algicid, brush applied undiluted and allowed to remain undisturbed for three hours before thoroughly washing off.

Manufacturer recommends the use of Keim Restauro Fixativ, a liquid silicate binder used to dilute Keim Restauro Lasur and also used as a neat primer coat to reduce surface porosity. Apply a coat of by brush and work well into all surfaces.

General information









Ss_15_30_15_50 Masonry cleaning systemsPrimary


M60/170 Masonry coating

M60/18 Special coating

Specification data - Masonry cleaning systems


Keim Restauro Fuge.

Keim Restauro Grund.

Keim Restauro Top.

Treatment/ Decoration

Keim Lotexan N.

Keim Restauro Lasur.






Environmental information

Country of material origin


Country of product manufacture



Keim Mineral Paints - Stone Brochure

Keim Mineral Paints - Stone Brochure

Listed & Historic Buildings

Listed & Historic Buildings