The Keim Restauro System provides 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.
– 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. Keim Silex OH should be flood coated over all areas using a brush or low pressure spray until the substrate can absorb no further material. Excess material should then be blotted off using clean, dry, lint free cloths.
– Restoration mortars:
- Keim Restauro Grund: A pre-mixed, dry bagged mineral ground restoration mortar (grey colour only). Having cut the stone back to a sound base, Keim Restauro Grund mixed with clean cold water to a moist earth consistency should be applied to the level of approximately 5 mm below the finished surface. This is only suitable if the depth is in excess of 10–15 mm.
- Keim Restauro Top: A pre-mixed, dry bagged mineral finishing restoration mortar (available in lightfast stone shades, consult manufacturer). Keim Restauro Top, mixed with clean cold water to a moist earth consistency, should be applied proud of the surface using a trowel, allowed to harden and then dressed back in a manner to suit the surrounding stonework. If necessary stainless steel reinforcements, screws and wires can be used to hold repair materials in place until the mortar is dry.
- Keim Restauro Fuge: A mineral, dry bagged pre-mixed restoration mortar with hydraulic binders for joint replacement. Keim Restauro Fuge is to be mixed with clean cold water and after a ripening period of five minutes the mortar should be of light flow properties. For moulding silicate resin moulds should be used. Press the prepared joint mortar firmly into the joint with a jointing tool. The new joint material should not be smoothed at the surface. For flush joints, Keim Restauro Fuge should be applied proud of the stone surface and any excess then removed with a palette knife during setting.
– 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 which penetrates the surface of stone, equalising repairs and variations, while maintaining the structure and appearance of natural, unpainted stone. For use on mineral substrates. It provides long-term decoration and is available in a wide range of standard colour shades. After a minimum period of 12 hours, apply Keim Restauro Lasur in the required colour diluted with Keim Restauro Fixativ, a liquid silicate binder, to the required level.
The system is available in standard shades from the Naturstein colour range, as well as colour matches and bespoke colours.
- 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 period 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.
Suitable for use on unpainted surfaces.