THERMOCOAT WI INTUMESCENT PAINT FOR STRUCTURAL STEEL AND CAST IRON
Thermocoat WI is a low-odour, water-based coating, making it user and environmentally friendly. The range of topcoats are
either water-based or 2010 compliant and safe to use in accordance with manufacturer’s instructions.
Dry Internal: Apply Thermocoat WI in accordance with Thermoguard film thickness schedule to achieve 30, 60, 90 minutes.
Visible or occasional modest damp internal areas: Also apply 1 good coat Thermoguard Flame Retardant Paint
Wet or External Under Cover: Apply 2nd coat Flame Retardant paint
Full External Exposure: Contact Technical Dept.
Thermocoat WI can be topcoated with Flame Retardant gloss, eggshell, WB satin, WB matt BS 4800 & RAL colours
Thermocoat WI is optimised to protect I, channel, shaped steel and hollow bracing. It is a water-based intumescent paint
system providing fire resistance to structural steel and cast iron of up to 90 minutes with a minimum number of coats. A
compatible decorative overcoat system ensures the system will enhance the building’s architectural and design features.
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.
Available in 20kg, 5kg, 2.5kg
Prior to application the contractor should contact Thermoguard’s Technical Department and obtain a basecoat
application schedule or follow on can guidance. Do not overspread as this will compromise the system and
result in non-compliance and a failure to be certified
Brush/roller application Surface dry: minimum 2 hours
Recoat: minimum 4 hours
Overcoating with Flame Retardant finish: minimum 10 hours
Spray Application Surface Dry: minimum 4 hours
Recoat: minimum 10 hours
Overcoating with Flame Retardant finish: minimum 48 hours
Steel and cast iron should be free from rust and millscale and primed with Thermoguard Steel Fire Paint Primer to 75 microns
DFT ( or alternative good quality anti-corrosive primer compatible with intumescent paints) in accordance with manufacturer’s
instructions. Treat galvanised surfaces with “T” wash/Mordant solution & prime with zinc phosphate or other primer for steel.
Maximum Relative Humidity 80%
Minimum ambient temperature 4°C
Minimum Steel Temperature 3°C above Dew Point
Thermocoat WI 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 Thermoguard’s Technical Department and obtain a basecoat
application schedule. To assist correct application in accordance with this schedule, a wet film gauge will be supplied with the
order. Further wet film gauges will be provided on request.
Maximum wet film thickness per brush coat – 800 microns
Maximum wet film thickness per spray coat – 1400 microns
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 319, 321, 419, 421
Care should be taken to clean filters regularly. Cleaning should be undertaken with water
Thermoguard issue a Certificate of Supply on request for each specified project for insurance, Fire and Building Control Authority
and Client Records.