Seal Flex

Acrylic Membrane Free Waterproofing


  • Easy to use
  • Membrane Free Fibre Reinforced
  • Available in Standard Colours


Category: .

Product Description


Please note colours displayed are for illustrative purposes and vary according to your computer graphics, the final painted colours may depend on surface conditions, previous surface treatments and the effect of light and shade.


GENERAL DESCRIPTION: A highly flexible, fibre-reinforced modified acrylic waterproofing product which can be applied by brush or roller. No fabric reinforcement necessary. May be applied in one or two coats and can be used to treat difficult areas and joints where conventional waterproofing cannot be applied.

USES: Waterproofing of properly prepared parapet wall capping, flashings and joints. Sealing of roofs and exterior masonry walls. Not recommended for use over bitumen systems. Waterproofing of flat roofs (e.g. concrete, IBR-zinc sheeting) Localised sealing of joints, fastener heads etc. (NB reinforcing fabric recommended for joints) Waterproofing of timber and chipboard roofs.


  • Fibre reinforced
  • Highly flexible
  • Excellent adhesion properties


PHYSICAL FORM: Non-flammable, water-based pseudoplastic viscous coloured mastic

COLOUR: Wide variety of standard Roman colours

FINISH: Medium Sheen, highly flexible film

SPREADING RATE: Approximately 0,5m² per litre (2 litres / m²) per application

POLYMER TYPE: Modified flexible acrylic latex

FILLERS: Non-toxic, weather resistant types

PIGMENTS: Non-toxic, weather resistant types

DRYING PROPERTIES: Surface or touch-dry: within 1 hour

RECOATING TIME: 6 hours depending on conditions during drying

FLASH POINT: Not flammable in liquid form


THINNING: Product is ready for use




GENERAL DESCRIPTION: Versatile one-component high performance waterproofing product. The product forms a watertight membrane moulded to the contours of the substrate. It can also be used to bridge cracks of up to 2mm width without use of crack filling compounds.


1. Surface preparation: Surfaces must be clean, sound and free from loose materials Notes: a) Metal surfaces must be primed with RB10 Multi-Prime metal primer. b) Masonry surfaces may be friable – apply Bondseal before continuing to ensure surface is sound before applying RB10 Seal Flex.

2. First Coat: Apply undiluted product to prepared surface. Ensure that the film thickness is at least 1mm thick (2mm is optimum) and that the coating is uniform. Allow drying for at least 4 hours before continuing.

3. Second coat: Apply second coat as described above.

4. Weather coat: Apply Pro-Roof or the selected finishing coating over the waterproofing system.

5. Joints: Embed RB10 BIDIM polyester fabric into the first coat and saturate while still wet with a fresh coating. This increases the film strength over joints. Leave to dry for 6 hours then re-apply RB10 Seal Flex as described above.

OVERALL COVERAGE RATE: Depends on the surface being treated. An approximate guideline is as follows: RB10 Seal Flex: 2 Litres l per m² per application = (2mm film thickness).

ADDITIONAL INFORMATION: Suggested specification clause for tender and other documents: Prepare and apply RB10 Seal Flex Waterproofing system in accordance with the method given in this specification sheet and using materials supplied by RB10 Paints. Such work is to be undertaken by a specialist-waterproofing contractor approved by the specifier and RB10 Paints. All information contained in this document is given in good faith and is based on experience and field-testing. However, no guarantee is given or implied as conditions such as handling and application are beyond our control.


Concrete Roofing (New): Inspect condition of screeding: repair if necessary Scrape off loose materials from surface and sweep clean. Carry out Standard Application Procedure

Roofs previously waterproofed with asphalt, malthoid or roofing felt: Remove all loose materials from surface, clean out cracks. Fill the cracks. Apply RB10 Seal Flex for step 2 of Standard Application Procedure. Carry out remaining steps of Standard Application Procedure.

Fibre-cement roofing: Clean down thoroughly using water and wire brush. Treat fungal or algal growths with RB10 Anti-Fungicide cleaner & treatment. Allow to dry then rinse thoroughly, (Refer to the product data sheet). Spot prime metal fasteners (screw/nail heads) with RB10 Multi-Prime metal primer. Fill small cracks (up to 2mm width) by applying RB10 Seal Flex to the crack & allow drying. Fill larger cracks. Allow drying and sand smooth. Carry out Standard Application Procedure over entire roof area.

Galvanized Iron Roofing: Clean down thoroughly using water and wire brush. Sand down red-rusted areas to bare metal and dust off. Then apply RB10 Galv-Prep Etch Cleaner to remove surface contaminants (oils, contamination etc.). Rinse thoroughly. Spot-prime all nail & screw heads with RB10 Multi-Prime metal primer. Seal any holes and open joints by applying RB10 Seal Flex undiluted followed by embedding reinforcing fabric into the wet sealer (open joints and holes greater than 2mm diameter). Allow sealer to dry. Carry out Standard Application Procedure to the patched areas. Apply two coats Pro-Roof roof paint over the roof area to provide a uniform appearance.

New Timber Roofs: Ensure the timber is fully dry before starting. Apply Pink Wood Primer in place of the Priming stage of the Standard Procedure.

Flashings: Carry out the Standard Application Procedure. Apply reinforcing fabric if joints are present.

Roof Extended over Parapet Wall Capping: Carry out the Standard Application Procedure. Ensuring that the coating of RB10 Seal Flex extends over the parapet capping to below the level, which may vary between 100mm to 300mm of the roof on the outside vertical faces and onto the roof surface on the inside.

Parapet Wall Capping: Carry out the Standard Application Procedure. Ensuring that the coating of RB10 Seal Flex must be dressed, which turns down the outside vertical faces of the wall between 100mm to 300mm preventing moisture ingress underneath the wall capping or top of the wall upstand.

Expansion Joints: These are normally sealed using polysulphide or polyurethane sealants. Sometimes a foam insert is also used to reduce the volume of sealant required. RB10 Seal Flex may be applied over sealed expansion joints but should not be used as a joint sealer.

General: Different surfaces require different preparations before applying RB10 Seal Flex. Contact a RB10 Sales Representative or the factory for further Technical Advice. It is recommended that the coating system be inspected after 3 years and a maintenance coat be applied if necessary.

HEALTH & SAFETY: Keep paint away from children. Never smoke, drink or eat while painting. Wear protective overalls, gloves and goggles. If accidental contact with skin should occur, wash immediately with clean water. Harmful if swallowed. Do not induce vomiting. Consult your doctor. Ensure good ventilation during application and drying. Store in a cool, dry place out of the sun.

DISCLAIMER ADVICE: The information given in this Product Information Sheet is based on controlled laboratory tests and many years of experience. It is given in good faith but no guarantee of any performance characteristic is given or implied. RB10 paints cannot be held liable for consequential damage of whatsoever nature that may arise from the use of RB10 products. Paint technology is continuously being developed and RB10 Paints reserves the right to update product specifications without prior notice. Contact RB10 Paints for further details.

Technical Data Sheet

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Safety Data Sheet

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