We no longer stock this product, but can recommend Thermoguard Thermocoat WI Ultimate for Universal Beams, Columns and other open section steel, and Thermoguard Thermocoat WO Ultimate for CHS, SHS and RHS hollow sections, as great alternatives.
Economy and Speed
Thermocoat W is an economical, water based intumescent paint system providing fire resistance to structural steel and cast iron for up to 120 minutes with a minimum number of coats. A compatible decorative overcoat system ensures the system will enhance the building’s architectural and design features.
It is designed for use on larger projects, where our technical team can advise the exact amount of Thermocoat required, keeping costs down and making application easier.
Please note that this product CANNOT be used without first recieving an application schedule from our Technical Department. Please download and complete the 'Thermoguard Steel Enquiry Form' and return by email to [email protected]
See Thermoguard Thermocoat WI, optimised for Universal Beams, Columns and other open section steel:

For optimised protection on steel hollow sections, see Thermoguard Thermocoat WO Ultimate:

For protection to exterior environment steels, please refer to Thermoguard Thermocoat S.
If you have any questions regarding this process consult our technical department on 0113 2455450 (option 2).
Thermocoat W is a low odour, water-based coating, making it user and environmentally friendly. Thermoguard Flame Retardant Topcoats are 2010 compliant and safe to use in accordance with manufacturer’s instructions.
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How it Works
The heat of a fire triggers a catalytic reaction, causing the expansion of an insulating char layer up to 50 times the paint thickness. This layer keeps the steel below its critical temperature, thus maintaining the structural integrity of the building.

Fire Testing
Product performance assessment based upon UKAS/EGOLF Fire Test Laboratory Certification to BS 476 Part 21 - Fire resistance to load bearing elements of structures.
Fire Certification
After use, a Certificate of Supply can be issued upon request for each specified project for insurance, Fire and Building Control Authority and Client Records. Click HERE to apply.
Preparation and Pre-Treatment
Specification
- Dry Internal: Apply Thermocoat W in accordance with film thickness schedule supplied by Technical Department to acheive 30, 60, 90 or 120 minute protection.
- Visible or occasional modest damp internal areas: Also apply 1 good coat Thermoguard Flame Retardant Topcoat (available in Gloss or Eggshell finishes).
- Wet or External Under Cover: Apply 2nd coat Thermoguard Flame Retardant Topcoat (available in Gloss or Eggshell finishes).
- Full External Exposure - Contact Technical Department.
Application
- Thermocoat W may be applied by brush, roller or airless spray. To achieve the best finish in the shortest time, spray application is recommended. Prior to application the contractor should contact the technical department and obtain an application schedule. To assist correct application in accordance with this schedule, a wet film gauge should be used, wet film gauges can be provided on request.
- Maximum wet film thickness per brush coat – 800 microns
- Maximum wet film thickness per spray coat – 1400 microns
Recoating
Brush/roller application
Spray application
Spray Equipment
Airless Spray Pump
Use equipment recommended by manufacturer for the application of high viscosity intumescent paints.
- Filter size 30 mesh. 10mm hose 3/8” diameter with no whip end
Tip Size
- Tip Size 323, 423, 325 or 425
Care should be taken to clean filters regularly. Cleaning should be undertaken with water.
Application Conditions
- Maximum Relative Humidity 80%
- Minimum ambient temperature 4°C
- Minimum Steel Temperature 3°C above Dew Point
Steel Terminology

Fire Exposure

Steel Types
- CHS: Circular Hollow Section
- SHS: Square Hollow Section
- RHS: Rectangular Hollow Section

IMPORTANT FIRE PRODUCTS NOTICE: The information displayed on this website should be used as a guide ONLY and our Technical Department should be contacted to obtain a tailored specification and any advice necessary before you place an order for fire protection products. Fire protection products are non-returnable except in accordance with Condition 8 of the Terms and Conditions and should be applied only by an individual with the necessary expertise and experience. We will not be held liable for any resulting damage to property, human life or monetary costs incurred due to the incorrect specification you have prepared or use of fire protection products caused by your negligence, including your failure to have contacted us to obtain the relevant advice/specification.