All Surfaces must be free from oil, dirt, dust and loose debris. Cromaprufe Emulsion can be applied to damp but not waterlogged surfaces. Porous and hot dry surfaces should be dampened with clean cold water to assist the application of the product.
- Stir well before use.
- Apply by Brush.
- Do not apply to external surfaces in wet weather or if rain is threatened.
- Allow good ventilation in confined areas.
- In multicoat applications, each coat should be allowed to dry completely before the next coat is applied.
Waterproofing and protection of Structures, Foundations, Retaining walls and bridge abutments:
Apply two coats each at 2 m² per Litre. When treating foundations, the coating should be taken to meet the damp proof course provided in the base or wall. Cromaprufe Emulsion may be applied to green concrete surfaces after the shuttering has been removed to act as a curing membrane. It is recommended that 48 hours be allowed to elapse before backfilling.
Concrete beams and columns:
Cromaprufe Emulsion may be used to provide a damp-proof membrane on concrete beams and columns before they are clad with rendering, masonry or brickwork. Two coats of Cromaprufe Emulsion should be applied, each at 2 m² per Litre. When the second coat has become tacky it should be bonded with 1 - 2 mm stone chippings or a clean sharp sand.
Walls:
If rising damp is at all suspected, the best method of prevention is the insertion of a damp-proof course or the repair of the existing one.
Exterior:
Remove all dirt, dust and grease. If the surface is uneven it should be levelled using cement mortar. Bare brickwork should be covered with a thin skin of cement mortar, which should be allowed to dry. Apply three coats of Cromaprufe Emulsion each at 2 m² per Litre. The final coat should be bonded with clean sharp sand while it is still tacky.
Interior Walls with Moderate Dampness:
Remove the wallpaper, loose distemper paints, dirt, dust and grease and make good any damaged or perished plaster. Lightly dampen the prepared surface and apply two coats of Cromaprufe Emulsion each at 2 m² per Litre. A section of the wall (about 300 mm) should be left untreated so that any trapped moisture may evaporate away. When decorating over Cromaprufe Emulsion do not use gloss paints or other oil based products. Emulsion paints and wallpapers may be used after first hanging a lining paper, fixed with cellulose paste. Do not use wallpapers based on vinyl.
Interior Walls with Extreme Dampness:
Not advised for interior walls below ground level. It is recommended to treat on the outside as Cromaprufe Emulsion is unlikely to resist exposure to free water or water pressure, conditions which are often found in basements and cellars.
Floors:
Sandwich construction - severe conditions and penetrating damp. Apply two coats of Cromaprufe Emulsion onto the smooth, clean concrete subfloor, each at 1 m²/L. Whilst the second coat is still tacky, bond with clean sand, as a protection against foot traffic and to provide a good key for the top screed. It is important that the Cromaprufe Emulsion membrane is taken up the walls to marry with the existing DPC and that the dried film is not punctured or damaged. Apply the top finishing screen to a thickness of at least 50 mm and allow to dry out thoroughly before laying a floor covering.
Surface Treatment on Existing Floors:
Where severe dampness is unlikely to occur, a surface treatment with Cromaprufe Emulsion will prove an efficient precautionary measure (however, the sandwich construction as described above should always be undertaken if conditions are severe and damp is penetrating). Apply a priming coat at 7.5 m²/L by diluting 1 part Cromaprufe Emulsion with 6 parts clean cold water and allow to dry thoroughly. Two coats of Cromaprufe Emulsion each at 1 m²/L should then be applied. Each coat should be taken up to the joint with the existing DPC and the dried film of Cromaprufe Emulsion should not be punctured or damaged before the floor covering is laid.
As an adhesive for wood blocks and wood mosaics:
If damp conditions are expected, first treat the floor as described under ' floors' above. Ensure that the surface is level and clean. Lightly prime, but do not over-wet, the surface with clean cold water. Pour some Cromaprufe Emulsion into a shallow tin and dip each wood block separately into the adhesive, coating only the underside and half way up the sides. Press the blocks home firmly, taking care to exclude air. When fixing wood mosaic panels, spread Cromaprufe Emulsion onto the screed at 0.8 m²/L and immediately place the panels into position.
Note: On non-porous floors allow the film of Cromaprufe Emulsion to become tacky (30 - 40 minutes) before laying the panels.
Where underfloor heating has been installed, this should be turned off and the floor allowed to cool prior to laying blocks or mosaics. Allow 48 hours before turning back on again.
Plastering on difficult surfaces:
Cromaprufe Emulsion may be applied to surfaces that have poor keying properties e.g. gloss painted walls, old tiles, etc. to permit the application of plaster. The surface, which should be free from grease and dirt, should be coated with two thin layers of Cromaprufe Emulsion at 4.5 m²/L. Whilst the second coat is still tacky it should be bonded with clean sharp sand and allowed to dry for 48 hours before plastering according to Plaster Manufacturers recommendations.
