Stogursey Castle

Limewash With Tallow

RJ3.03

A traditional natural permeable paint for the decoration of lime renders, limestone, soft brick and porous building materials. Tallow is added to the hot slaking lime to improve the rain-shedding properties. Some of the tallow reacts with the alkaline lime to form an insoluble calcium soap; the rest of the fat is dispersed by this soap and binds the mixture together. Limewashes do not ‘dry’ like modern paints but ‘set’ by reaction with atmospheric carbon dioxide in the presence of moisture. For Exterior use – rarely used internally.

Environmental Considerations: 

Limewashes are made with natural sustainable ingredients. They contain no VOCs, no petrochemical based ingredients, and no lead. Water-based. All Rose of Jericho paints comply with the latest environmental legislation. This product contains both a fungicide and an algaecide.

Colours: 

All colours except those marked with an *asterisk on colour charts C9 and C10 + White. Colour matching service available.

Colour Charts

Finish: 

Matt surface coating. Colours are darker in tone when wet.

Shelf Life: 

The tallow tends to coagulate and Tallow Limewash should be used within one week of manufacture. Casein limewash must be stored in a cool frost-free environment, away from heat and direct sunlight. Tins and tubs must not be kept in the van in sunny weather and must be moved to a cool/cold environment.

Coverage: 

Approx. 4 –5 m2/litre/coat depending upon texture and porosity of surface.

Availability: 

5 litre cans & 15 litre tubs. Limewashes are mixed to order and can normally be supplied within 48 hours.

Health & Safety: 

See Health & Safety Data RJ5.03C

CAS No 1305-62-0.

EINECS No 215-137-3.

Alkali (pH 13).

H302 Harmful if swallowed.

H315 Causes skin irritation.

H318 Causes Serious Eye Damage.

Technical Advice: 

Limewashing can be messy, and full protections must be provided to all vulnerable adjacent surfaces. In particular, any oak or oak flooring must be fully protected, as the alkali lime permanently stains hardwoods. Newly applied exterior Limewash must be fully protected from rain, wind, direct sunlight, frost, etc. until it has cured and carbonated (normally about 4 weeks).

Preparation: 

Limewash with Tallow requires a surface that is firm, clean, and porous. It can be applied to new lime render before it has carbonated, but Tallow Limewash is less permeable than Pure or Casein Limewash and will slow the rate of carbonation of the render beneath. Limewash with Tallow can be applied to previously tallow-limewash painted surfaces, but not to other paint types. Sample trials should be undertaken. Previously limewashed surfaces should be thoroughly brushed and washed with a wet sponge to remove dust, dirt and all loose, chalky material that is removed readily. All mould and algae must be treated with a fungicidal wash that includes an algaecide and thoroughly washed off with clean water. Do not use fungicides containing water repellents. Make good and fill with a compatible material/filler. Limewash with Tallow should be applied to damp surfaces. Lime plaster and render, porous stone and brick must be thoroughly moistened with a mist spray prior to application.

Application: 

Ensure Limewash has been made within the previous week. Limewash with Tallow must be thoroughly mixed, preferably with a mechanical whisk, to ensure even distribution of pigments and ingredients immediately before and during use as it readily settles out. Protective clothing and goggles must be worn and great care taken. Surfaces must be damp. Porous pre-wetted surfaces may need additional mist-spraying during application to ensure that the limewash does not dry too quickly. Apply the limewash to the damp surface using a brush, not a roller, working it into any cracks. It is applied in thin coats- the limewash appears transparent on application and care must be taken to avoid thick build-up which will craze on drying out and may obscure detail. Normally, 3 coats are required, occasionally more. Each coat must be protected from drying too quickly by regular mist-spraying, and a reasonable time (at least 24 hours, often longer) allowed between coats. It is normal to mist-spray the previous coat prior to the application of the next coat. Protections. Limewashing can be messy, and full protections must be provided to all vulnerable adjacent surfaces. In particular, any oak or oak flooring must be fully protected, as the alkali lime permanently stains hardwoods. Newly applied exterior Limewash must be fully protected from rain, wind, direct sunlight, frost etc until it has cured and carbonated (normally about 4 weeks).

Observations: 

Limewash with Tallow is an exterior grade limewash used for the decoration of lime renders, porous building materials, and previously tallow-limewashed surfaces in the more exposed locations. Casein limewash is normally preferred on less porous surfaces. It is less permeable than both Pure Limewash (RJ3.01) and Casein Limewash (RJ3.02) Coarse textured wood or sponge floated surfaces are far preferable to smooth steel-trowel polished surfaces. Sample trials should always be carried out to assess compatibility with substrate. Coloured limewash is made using natural powder pigments. Colour and tone variations due to these pigments and differing porosity of surfaces are inevitable. Much of the charm of a traditional finish is its lack of uniformity with subtle variations of colour and tone.

Limitations: 

Tallow Limewash cannot be used on previously painted surfaces unless the existing paint is limewash. Tallow Limewash should be protected from drying too quickly, and from rain and wind before carbonation. Tallow Limewash is not suitable for use on ‘sky-facing’ surfaces, weathering details or in very exposed