Mould renovation plaster

KREIDEZEIT Mould Renovation Plaster is a white, mineral finishing plaster of mortar group P I a made from air lime, marble sand and expanded vermiculite. It has a high water absorption capacity (1.0 l/m² at a layer thickness of 3 mm).

Where condensation forms on cold wall surfaces, a film of moisture develops on which mould grows. This plaster immediately absorbs this moisture at the surface and releases it back into the room air. This makes it a proven material for dealing with mould caused by condensation. Only KREIDEZEIT Sumpfkalkfarbe may be used as a paint finish.

Properties

• Powder for mixing with water, shade: white
• mineral finishing plaster, mortar group P I a, grain size max. 1.5 mm
• Water absorption 1.0 l/m² at 3 mm layer thickness
• highly vapour-permeable: sd value < 0.03 m at 3 mm (DIN EN ISO 12572)
• splash-proof
• strongly alkaline (fresh application pH > 12.5)
• mineral, odourless once cured
• free from preservatives
• can only be painted over with KREIDEZEIT lime putty paint
• vegan

Suitable substrates

Sound, absorbent, mineral substrates indoors: lime, lime-cement, lime-gypsum and cement plasters, masonry, stone. Gypsum plasters/plasterboard/gypsum fibreboard on request. Unsuitable: wood, clay plasters, emulsion paints, oil paints, synthetic surfaces, smooth or permanently damp substrates.

Use & Application

Pre-wetting: Pre-wet absorbent substrates until saturated with water, or preferably with lime sinter water, and do not allow them to dry out.

Mixing: Stir 0.35–0.40 l of water per kg of powder using a powerful mixer and leave to swell for at least 15 minutes. Some subsequent thickening is normal; adjust the consistency on site.

Application: Apply 3–5 mm thick to the pre-wetted substrate; once it has begun to set, rub up with a sponge float or rubbing float. Maximum application thickness 10 mm. Application and curing temperature 7–25 °C.

Setting: During setting (2–3 days), allow to dry slowly only, lightly re-moisten 1–2×, and avoid draughts and direct sunlight.

Coating: Use KREIDEZEIT Sumpfkalkfarbe only – other coating systems impair its function.

Drying: At least 1 day per mm of application thickness.

Technical data

Mortar group	P I a (air lime)
Grain size	max. 1.5 mm
Water absorption	1.0 l/m² at 3 mm
sd value	< 0.03 m at 3 mm layer thickness (DIN EN ISO 12572)
Application thickness	3–10 mm
Coat of paint	KREIDEZEIT lime putty paint only

Full declaration

Marble hydrated lime, marble sand, expanded vermiculite, cellulose, methyl cellulose. The complete product information (technical data sheet and safety data sheet) must be observed during application.

Note: Lime products are strongly alkaline – protect eyes and skin. The plaster is no substitute for eliminating the cause of the damp. Observe the safety data sheet.

Frequently asked questions

How does the plaster reduce the risk of mould?
Mould on interior walls usually develops on the film of moisture that forms when condensation occurs on cold surfaces. The plaster immediately absorbs this condensation moisture at the surface (1.0 l/m² at 3 mm) and releases it back into the room air, so no permanent film of moisture forms. The cause (thermal bridge, ventilation) should also be remedied.

What must I paint over it with?
Only KREIDEZEIT Lime Putty Paint. Other coatings seal the pores and impair moisture absorption.

Which substrates can I use it on?
On firm, absorbent mineral plasters, masonry and stone indoors. Not on wood, clay plaster, emulsion paints or permanently damp surfaces.

How thick is the plaster applied?
3–5 mm in one pass, maximum 10 mm in total. Drying time at least one day per mm.