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For use in flat roofing applications where regulations specify a fire-retardant system. Conforms to BS476 Part 3:2004, FAB classification.
- Pre-pigmented, isophthalic acid based, filled fire-retardant roofing top-coat
- Excellent water and weather resistance providing a maintenance-free surface
- Tack-free and water-tight
- Exhibits good levelling characteristics and sag resistance on inclined surfaces
- Designed for roller application
- Part of the Cromar Pro GRP Roofing System
Cromar PRO GRP Topcoat is a dark grey, pre-pigmented, isophthalic acid based, filled fire-retardant roofing top-coat that conforms to BS476 Part 3:2004, FAB classification. Recommended for use in flat roofing applications where regulations specify a fire-retardant system.
Designed for roller application which exhibits good levelling characteristics and sag resistance on inclined surfaces. The cured top-coat is tack-free and water- tight with excellent water and weather resistance providing a maintenance-free surface.
What is PRO GRP?
GRP stands for Glass Reinforced Polyester and is also known as Glass-Fibre.
This system is cold applied on site, giving it a seamless and flexible weatherproof finish that resists water, heat and frost.
The resulting surface gives a strong architectural finish that looks very impressive. If maintained properly it will last as long as the building stands.
Cromar have developed this technology further to produce the perfect all weather protection for any flat roof. PRO GRP can be applied in small domestic situations right through to large industrial environments.
Benefits of a GRP System
- COLD APPLIED - no heat required
- EASY TO FORM - around complex situations
- VERY DURABLE - resists heavy foot traffic
- NON-SLIP WALKWAYS - can be incorporated
- CLASS LEADING ROOFING SOLUTION - that far exceeds traditional methods
- VIRTUALLY MAINTENANCE FREE - for very long periods of time
- IMPACT RESISTANT - due to its ultra hard finish
- FIRE RETARDANT
- HIGHLY ECONOMICAL SOLUTION
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Features & Benefits
- Excellent water and weather resistance providing a maintenance-free surface
- Tack-free and water-tight
- Exhibits good levelling characteristics and sag resistance on inclined surfaces
- Designed for roller application
- Conforms to BS476 Part 3:2004, FAB classification
- For use in flat roofing applications where regulations specify a fire-retardant system
- Part of the Cromar Pro GRP Roofing System
Application
For full application instructions download the PRO GRP Installation Guide.
Cromar PRO GRP Topcoat is designed for use at ambient temperatures between 18℃ and 25℃, and requires the addition of 2% medium activity MEKP catalyst to achieve an efficient cure.
For optimum performance the top-coat should be applied to a dry, dust-free surface and built up to film thickness of 500 - 600 microns to achieve the desired fire retardant characteristics in the finished structure.
Before use, the temperature of the top-coat should be 18 – 25℃. For application at lower ambient temperatures a high activity MEKP catalyst can be used at an addition level of 2%.
Coverage
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The values above are recommended coverage rates for estimating purposes we would recommend coverage rates or 1.5kg/m 2 for resin, and 0.5 kg/m 2 for top coat.
Liquid Gel Coat Properties
Liquid properties | Thixotropic |
Gel time @ 25℃ | <15 minutes |
2% medium activity MEKP |
Health & Safety
Please refer to the Safety Data Sheet on Cromar PRO GRP – Topcoat, downloadable from the "data sheets" tab towards the top of the page.
Always read and understand the Safety Data Sheet before working with this product.
Directly mixing any organic peroxide with a metal soap, amine or other polymerization accelerator or promoter will result in violent decomposition.
Data sheet
- Manufacturer
- Cromar
- Interior / Exterior Use
- Exterior Use
- Water / Solvent Based
- Solvent
- Application Method
- Roller
- Colour
- Standard / Ready Mixed
- Single, Two or Three Pack
- Single
- Pack Size
- 10KG, 20KG
- Coverage
- 0.5 kg/m2
- Max. Application Temperature
- 25℃
- Min. Application Temperature
- 18℃
- Base Type
- Acid-Based
- Suitable For Use On
- Flat Roofs
- Application Method
- Roller
- Product Usage Type
- Topcoat
- Product Range
- Pro GRP
- Colour Family
- Grey
Questions
Question about the product
![]() | Question: Our builder used a Cromar Pro GRP Roofing Kit to cover our flat roof porch. The top coat coat has cracked in a couple of places. Am I ok to put another layer of Top Coat directly on top of the existing top coat. I have brushed it down and washed it, is there any other prep that I would need to do? |
Answer from Rawlins’ Technical Team: No, re-applying topcoat directly to a previous coating of topcoat wouldn't work in this instance. Assuming the existing coating is clean, dry, sound and lightly abraded, we'd recommend applying Acetone to the roof to clean the surface, followed by a thinly layered coat of Cromar PRO GRP Resin, before another coat of Cromar Pro GRP Topcoat to finish. | |
![]() | Question: Hi, I have a GRP structure that needs to be waterproofed and repainted in green. Can you please advise as to what products will work best. Thanks |
Answer from Rawlins’ Technical Team: Thank you for the enquiry, please can you provide more information and pictures of the area in question to technical@rawlinspaints.com so we can assist with a specification. | |
![]() | Question: Hi I have a grp roof which is going to be walked on what material should i sprinkle or mix in with the topcoat. Regards Mark |
Answer from Rawlins’ Technical Team: Assuming the topcoat being used is Cromar Pro GRP Topcoat we can recommend Cromar Scangrit Grade 6 Antislip for mixing with the topcoat to provide an antislip surface. | |
IMPORTANT SHIPPING & DELIVERY INFORMATION
Cromar PRO GRP Topcoat is only available with the shipping and delivery timescales listed below - please do not contact our Customer Support Team with enquiries about alternative or earlier shipping and delivery times.
Saturdays and Sundays, as well as Bank Holidays, are not classed as working days.
Orders placed after the cut-off for this product will not be processed for earliest dispatch until 9am the next working day.
All delivery costs below are excluding VAT
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£4.95
Economy: 7-10 Working Days Nationwide Delivery
Order before tomorrow - 15:00 and get your delivery between 7 and 12 March