Breathable Cement-Free Scratch Coat for Damp, Salt-Affected & Heritage Masonry

Mape-Antique Rinzaffo is a salt-resistant, breathable scratch-coat mortar designed as the first coat in de-humidifying, breathable and “structural” render systems. It is formulated for old masonry affected by capillary rising damp, concentrated salts, ageing and difficult substrate conditions, making it well suited to restoration, renovation and heritage repair work.

Made from lime, Eco-Pozzolan, natural sand, special additives and micro-fibres, this cement-free mortar improves adhesion, helps even out substrate absorbency and slows the transfer of salts before the main render coat is applied. It is suitable for stone, brick, tuff and mixed masonry, including buildings of historical and artistic interest and projects under conservation order or National Trust protection.

Key Features & Benefits

Breathable: Transpirant formulation allows moisture vapour to pass through the render system.
Salt-Resistant: Designed for masonry affected by saline efflorescence and concentrated salts.
100% Cement-Free: Lime and Eco-Pozzolan based scratch coat for more compatible renovation work on traditional masonry.
Improves Bond: Acts as a preparatory coat to improve adhesion of later render coats.
Regulates Absorbency: Helps even out suction on porous, weak and mixed backgrounds.
Heritage Friendly: Suitable for old buildings, listed building work and conservation-led repairs.
Machine or Trowel Applied: Suitable for manual application, with rendering machine application recommended for larger areas.

Typical Uses

First coat for internal and external macro-porous de-humidifying render on walls with capillary rising damp.
Base layer for de-humidifying render on stone, brick, tuff and mixed masonry with saline efflorescence.
Reconstruction of old lime-based render on traditional and heritage buildings.
Preparation coat on weak, porous or difficult masonry before breathable or “structural” render systems.
Suitable for masonry in coastal or lagoon environments exposed to salt action.

Product Details

Property	Value
Pack Size	20kg
Coverage	Approx. 7.5kg/m² per 5mm layer
Recommended Thickness	Approx. 5mm
Mix Ratio	25–27.5kg water per 100kg powder
Water Addition per Bag	Approx. 5.0–5.5 litres per 20kg bag for trowel application
Pot Life	Approx. 1 hour
Application Temperature	+5°C to +35°C
Colour	White
Aggregate Size	2.5mm max
Water Vapour Permeability (μ)	≤ 30
Compressive Strength	> 10 MPa
Bond Strength to Substrate	≥ 0.7 MPa
Reaction to Fire	Class E
Storage	12 months in original unopened packaging in a dry, covered environment

Application Instructions

Substrate Preparation: Remove deteriorated render, loose material, dust, mould and surface salts. On damp, salt-contaminated walls, remove render to around 50cm above the damaged area and clean with low-pressure water jets. Repair gaps and uneven masonry with compatible materials before application.
Dampen the Background: Saturate the substrate with water, then allow excess water to evaporate so the masonry is saturated but surface dry. If full saturation is not possible, dampen thoroughly.
Mixing: Mechanically mix only. For hand trowel application, add 5 litres of clean water per 20kg bag, then increase up to 5.5 litres if required. Mix for around 3 minutes, then a further 2–3 minutes until even and thixotropic.
Application: Apply a single coat of approximately 5mm to fully cover the substrate. Start from the lower part of the wall. Do not press or smooth over after application.
Overcoating: Apply the de-humidifying or breathable render once Mape-Antique Rinzaffo has started to set.
Curing: Avoid application in direct sun or strong wind, and protect against rapid drying. In damp internal conditions or cold weather, allow longer curing times.

Limitations

Not for use as a finish render.
Not for casting into formwork.
Not for injection slurry or consolidating grouts.
Not for use as an installation mortar.
Do not add cement, lime, gypsum or other additives.
Do not apply below +5°C.

Health & Safety

For safe handling, preparation and application, refer to the latest Safety Data Sheet. Product intended for professional use only.

Replastering