Description
Fastfix Wet Shield is a fibre-reinforced, one-coat roof and gutter repair membrane that can be applied straight onto wet or damp surfaces, supplied here in a 2.5kg tin in grey. It is made for emergency leak repairs, so you can seal a leaking roof without waiting for the rain to stop, and it also suits planned maintenance work in dry weather.
About the formula
A resin-based, solvent-based compound with reinforcing fibres that interlace to bridge small gaps and cracks. The manufacturer describes it as formulated from lightfast acrylic polymers, which helps it withstand UV exposure for longer than traditional bitumen coatings. It is waterproof the moment it goes on, so rain straight after application will not wash it off. It cures to a smooth, seamless, flexible membrane that resists algae and fungal growth. On sound, non-porous surfaces no primer is needed.
Where to use it
Indoors: not recommended for internal use.
Outdoors: roofing and gutter repairs, including tile and metal roofs, valleys, gutters, flashings, fascias, downpipes and cappings, plus concrete and brickwork. Areas that collect ponding water are covered by the one-coat system, provided the recommended minimum finished fall is achieved.
Suitable materials include concrete, fibre cement, roof tiles, slate, metal roofing, guttering, brickwork, lead flashing, uPVC, asphalt and bituminous roof coatings. Non-ferrous metals such as aluminium, copper and previously painted non-ferrous metals should be primed with a suitable etch primer first. If you are unsure about a surface, run a small adhesion test before committing to the whole job.
How to use it
Emergency wet repairs: no preparation is needed. Brush a thick coat over the affected area to create an immediate barrier against water ingress.
Planned dry-weather work: clear moss, lichen and debris by brushing, scraping or pressure washing. Let the surface dry, remove any oil or grease with white spirit, and let it dry again. Then apply the product generously with a brush, roller or squeegee in one coat.
Seal air-conditioning vents for at least 24 hours during and after application. Clean tools with white spirit or methylated spirits.
Important notes
- Not recommended for wooden surfaces, tanking, fishponds or internal use.
- Not designed for areas with heavy foot traffic.
- Allow up to 6 to 7 days to dry, depending on temperature and coat thickness. It may stay soft for longer in some climates, which does not affect its waterproofing.
- Manufacturer information recommends applying between 5°C and 25°C and a minimum finished fall of 1:80.
- Discolouration may occur over new asphalt, tar or bitumen.
- Shelf life is up to 2 years in an unopened container stored correctly.
- If a primer is needed on a particular substrate, check with the manufacturer for suitable options.
Specifications
| Brand |
Fastfix |
| Product |
Wet Shield One Coat Instant Waterproofing |
| Pack |
2.5kg tin |
| Colour |
Grey |
| Base |
Resin based, fibre reinforced, solvent based |
| Application |
Brush, roller or squeegee, one coat |
| Coverage |
1kg to 2kg per m2, depending on substrate |
| Drying time |
Up to 6 to 7 days, depending on temperature and thickness |
| Application temperature |
5°C to 25°C |
| Minimum finished fall |
1:80 |
| Flash point |
40°C (per SDS) |
| Clean up |
White spirit or methylated spirits |
| Use |
Exterior roofing and gutters |
Safety
Keep away from heat, sparks, open flames and other ignition sources, and do not smoke. Avoid breathing vapours, use in a well-ventilated area, and wear protective clothing, eye protection and face protection. For eye contact, rinse with plenty of water for 15 minutes holding the eyelids open. For skin contact, wash with soap and water. Refer to the Safety Data Sheet (SDS) for full details.
