Bostik Waterstop Emergency Grey Waterproofer, Tin
Product details
Product information
Product information
Bostik Waterstop Emergency Waterproof Coating is a high performance, flexible waterproof coating that stops leaks in flat roofs and gutters. It protects instantly, even when applied in the rain. This grey emergency roof repair can be applied to many substrates straight from the tin without a primer, including concrete, stone, wood, metal, zinc, clay, tiles, slate, felt, polystyrene, and most plastics. However, it is not suitable for use on polyethylene & polypropylene plastics, or bitumen coatings. It is long lasting and resists cracking, UV and frost.
- Instructions for Use - Store at room temperature. Prior to application, ensure that the temperature is above +5°C. Once open, the coating will start to cure. Apply immediately using disposable brushes. Bostik Waterstop Emergency Waterproof Coating will bridge and seal any cracks permanently. Cracks over 5mm should be completely filled and then covered with a suitable flexible scrim bedded into the coating. Apply two coats to a minimum thickness of 1.5mm per coat. Once the first coat has dried, approx. 4 hours, apply the second. In corners or areas prone to movement or cracking, a reinforcing scrim should be bedded into the first coat.
- Safety Information - Keep out of reach of children
- Guarantee - Statutory
Features and benefits
- Waterproof coating for emergency roof repairs
- Ideal for guttering repairs
- Stops leaks instantly
- Can be applied to wet or dry surfaces
- Free from solvent, bitumen and isocyanates
- No primer required
Specifications
| Application method | Brush |
|---|---|
| Brand | Bostik |
| Colour group | Grey |
| Container type | Tin |
| Location | Exterior |
| Maximum application temperature | 5°C |
| Minimum application temperature | 35°C |
| Model name/number | 30624374 |
| Pack quantity | 1 |
| VOC level | No VOC level recorded |
| Weight (g) | 1000g |
| Product code | 5010591014589 |
Safety Information
If medical advice is needed, have product container or label at hand. Keep out the reach of children. Contains Trimethoxyvinylsilane & N-(3-(trimethoxysilyl)propyl)ethylenediamine. May produce an allergic reaction.
This mixture is classified as not hazardous according to regulation (EC) 1272/2008 [CLP] EUH208 -Contains Trimethoxyvinylsilane & N-(3-(trimethoxysilyl)propyl)ethylenediamine. May produce an allergic reaction EUH210 - Safety data sheet available on request
P102 - Keep out of reach of children
Manufacturer / EU responsible person
EU responsible person
Bostik Industries
Address
IDA Buisness Park
51 Esplanade du Général de Gaulle
Arklow
Co. Wicklow
Y14 A370
Ireland
Contact
Reviews
4.69 / 5(26 reviews)Handyman 6969 - 4 / 5 - 21/02/2026
Does the job.
A good product if a tad expensive for emergency treatment of roofing water leaks
h0mepride - 5 / 5 - 21/02/2026
Quick acting conforming sealant
I bought this sealer to fix a hole in a flat roof. It spreads like Marmite then settles into the surface and self levels. 24 hours later it’s set like rubber and can be painted over. Beware, once you open the seal in the tin it starts to cure and any left in the tin will set.
Gorawada - 5 / 5 - 17/02/2026
Great product
Great product Easy to apply dries quickly Well worth the money
Rachel xx - 5 / 5 - 18/01/2026
Worth the money
Easy coverage and does the job Very impressed and good value
Mat76 - 5 / 5 - 30/12/2025
Great shed roof sealer
Re-sealed the joins in the shed roof with this. Used on a cold but dry day in mid December, dried to a rubbery texture within 24hrs as stated and sealed the roof perfectly, great stuff and did exactly what it was supposed to do
SelinaA - 5 / 5 - 24/11/2025
Love it
This stuff actually works and with minimal effort. We are currently renovating a house we bought and this has come in really handy for a couple of areas in the house. This stopped the moisture and was really easy to apply. Great value for money
HayleighD - 4 / 5 - 04/11/2025
Easy to apply, fast-drying, and seriously effectiv
The Bostik Waterstop Waterproofing Solution really impressed me with how easy it was to apply. The texture is thick and smooth, creating a solid, watertight seal almost instantly. It dries fairly quickly and forms a strong, flexible coating that seems durable even after heavy rain. I used it on a small leak area and it’s held up perfectly — no peeling, cracking, or seepage since. The tin goes a long way, and the finish looks neat and tidy once dry. A must-have for quick waterproof repairs or preventative sealing jobs around the home.
ElenaB - 5 / 5 - 27/10/2025
Great product for emergency repairs
I recently used Bostik Waterstop Emergency Waterproof Coating to fix a leak on my flat roof, and I’m very pleased with the results. The application was simple—just used a disposable brush (not included)—and it dried quickly. Remarkably, I applied it in the rain, and it still worked perfectly. The coating sticks well to various surfaces like concrete, metal, and tiles, without the need for a primer. Its flexibility means it doesn’t crack or peel with temperature changes, which is great for outdoor use. I also like that it’s environmentally friendly, free from solvents, bitumen, and isocyanates. The only downside is that it’s not suitable for polyethene or polypropyler plastics. Overall, it’s a reliable, versatile, and easy-to-use product perfect for emergency roof repairs. I’d definitely recommend it.
antoninad2_3905 - 5 / 5 - 27/10/2025
Good product, does the job
Only tried it on the gutters so far but Dried quickly, and it was easy to apply. I think it’s a great solution as an emergency coating, something you always should have at home in case
elizay3_6166 - 4 / 5 - 22/10/2025
Strong watertight coating
Very thick solution, no mixing required. Great coverage, dried quickly and is durable. Was easy to clean off skin after to make it a very usable product.