Wetterflex BG (Brush Grade)

Typical Uses:
Primarily designed for flat or pitched roofs. Also used to repair leaking valley and box-section gutters, glass/fibreglass roof lights and lead/zinc flashings.

Wetterflex BG is a brush-applied waterproof roof coating consisting of modified bitumens, mineral fillers, water-displacing agent and a specialist polymer. Wetterflex BG retains its flexibility to achieve exceptional adhesive strength to all roofing materials.

It may be applied in dry or wet conditions, during heavy rain or even under water, and is impermeable to water immediately after application.

Number of parts:1
Application Temperature:5oC to 30oC
Curing Time:Between 24 and 72 hours
Coverage:1m² per litre
Storage:Up to 24 months
Number of coats:1

Please consult the technical data sheet for full technical product data.

Preparation:
Thorough substrate preparation is essential.
All necessary remedial repair work should be carried out prior to application of the coating and the prepared surface should be clean, sound and free of flaking or loose material, moss or fungal growth.
Due to the wide variation in roofing materials and conditions, the following are generalised recommendations only. Please contact the Polycote technical helpline if more specific guidance is required for your application.
Moss, lichen and fungal growth – remove by stiff broom or jet washing, then treat the area with Polycote Destroy IT to inhibit further growth – see our relevant Data Sheet.
Porous surfaces – seal first with Polycote Roof Primer – see relevant Data Sheet.
Asphalt, bitumen and felt roofs – Remove all chippings. Blisters in asphalt can generally be left in place. Blisters in felt – should be cross cut, opened up and re-fixed using Wetterflex BG.
New asphalt and bitumen – surfaces should be allowed to weather prior to application.
Metal surfaces – remove all loose and flaking rust and treat with Polycote Rustex – refer to the relevant Data Sheet. New galvanised steel should be allowed to weather, or may be treated with a suitable primer – please contact the Polycote technical helpline.
Gaps, cracks, joints and holes – Wetterflex BG will fill or bridge small cracks up to approximately 1-2mm wide.
The use of Polycote Flexible Membrane is recommended – see ‘Application’.
Wide cracks or joints – should be raked clean, opened out and filled using Wetterflex TG (Trowel Grade) followed by the Flexible Membrane procedure.

Application:
To assist application in cold weather, store the material in a warm room overnight prior to use.
Stir thoroughly before use.
Having fully prepared the surface, first fill all gaps, cracks, joints and holes with Wetterflex BG, or Wetterflex TG if wider than 3mm.
Polycote Flexible Membrane should be used to reinforce repairs over any cracks or joints that are subject to movement. The membrane should be cut to approximately 100mm wide strips of appropriate length and laid into the Wetterflex over the cracks immediately, stippling with a paintbrush to integrate the membrane into the wet coating.
After all necessary membranes are embedded, an overall coating may be applied by brush. If this is done immediately, care should be taken when over-coating the placed membranes to avoid disturbing them.
If possible, allow overnight setting of the embedded membranes before over-coating the entire roof surface.
One overall coat is normally sufficient. Further coats may be applied if required, allowing drying intervals between coats.