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Thermoguard Thermoproof Exterior Fluid 5L

£125.99 (inc. VAT)
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Thermoguard Thermoproof Exterior Fluid 5L

Thermoproof Exterior is an exterior grade penetrating fire retardant fluid.

  • Natural finish
  • Allows wood to weather naturally
  • 3 coats on porous solid exterior wood
  • 5 litres covers 19 sq m
  • Class 1. 0 + B s1 d0

Thermoguard Thermoproof Fluid is a clear, one coat, penetrating liquid for protecting porous external timber from fire.

Intended use
Fire protection for porous external timber cladding and sheds.
How Thermoguard Thermoproof Fluid worksThermoguard Thermoproof Fluid
Thermoproof Fluid is a clear, colourless, penetrating fire protection fluid for wood.
Thermoproof Clear Sealer helps keep external wood clean and provides protection from the weather.

UKAS fire test standards
4 BS EN Class B s2 dO
4 Class O
For 30 or 60 minutes call us 01753 684084 or email

Fire certification 
Thermoguard issues a Certificate of Supply on request for each project for insurance, fire and building control authority and client records.

Thermoproof Fluid is clear and colourless. It can be left unsealed where weathering and cleaning are not relevant.
Thermoproof Clear Sealer gives a clear finish in matt or satin.

Thermoproof Fluid - 20 sq m & 80 sq m
Thermoproof Clear Sealer - 20 sq m & 80 sq m

Brush, roller or spray.
Apply to dry wood (Max 16% moisture), above 5°C in dry conditions.

Limitations stained, varnished or painted wood
For treatment with Thermoproof to be effective, it needs to be able to penetrate the wood.
Thermoproof can be applied over water based penetrating wood dyes that do not make wood waterproof.
To fire protect painted wood, see Thermoguard Timbercoat.
To fire protect clear normal varnished wood, use Thermoguard Fire Varnish and Matt or Satin Overcoat.
To fire protect stained varnished, woodstained or other coated wood, call us on 01753 684084 or email

New fire regulations & tests explained
The new fire standard BS EN test lasts 20 minutes with airflow and replaces the old BS 476 tests which lasted 10 minutes and strangely restricted airflow.
The new standard for flame spread and heat release Class B replaces Class O.
The new BS EN tests also monitor:
Smoke & Gas s s1 + s2 are none or very low & compliant levels, s3 moderate , s4 high smoke.
Flaming Droplets or Airborne particulates dO is none, d1 some, d2 + d3 moderate > high levels.

Environment & user friendly
Thermoproof Fluid, Thermoproof Clear & Woodstain Sealers are water based and environment friendly.
Refer to Health and Safety Data Sheet prior to using this product.

Quality assurance
Products manufactured under ISO 9000.

Call us on 01753 684084 or email for more advice.SaveSaveSaveSaveSaveSaveSaveSaveSave
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