Thermoguard Fire Varnish 30 & 60 Minute System
Thermoguard Fire Varnish 30 & 60 Minute System is a clear intumescent varnish for interior and exterior timber surfaces. These packs have been created to help users ensure they are purchasing sufficient product for their project. Each pack contains the correct amount of basecoat (Fire Varnish Basecoat) and topcoat (Fire Varnish Overcoat) to enable protection to be achieved to the respective area in question.
Transparent Wood Stains (interior packs only)
Representations shown below; represented as solid colours in the colour picker further above.
Each component of the packs can still be purchased individually if required here: Thermoguard Fire Varnish Basecoat and here: Thermoguard Fire Varnish Overcoat (Interior) or Thermoguard Fire Varnish Overcoat (Exterior)
***IMPORTANT: Please see detailed information following the text in RED below***
For fire protection to doors, see Fire Door Upgrade Kits
For BS Class 1/0 & EN Class B s2 d0 only see Thermoguard Fire Varnish BS Class 1/0 & EN Class B System
- 6.5m² Pack (Interior Spec.) = 1 x 20m² Fire Varnish Basecoat + 1 x 20m² Fire Varnish Overcoat (Interior)
- 6.5m² Pack (Exterior Spec.) = 1 x 20m² Fire Varnish Basecoat + 1 x 20m² Fire Varnish Overcoat (Exterior)
- 13m² Pack (Interior Spec.) = 2 x 20m² Fire Varnish Basecoat + 1 x 20m² Fire Varnish Overcoat (Interior)
- 13m² Pack (Exterior Spec.) = 2 x 20m² Fire Varnish Basecoat + 1 x 20m² Fire Varnish Overcoat (Exterior)
- 20m² Pack (Interior Spec.) = 3 x 20m² Fire Varnish Basecoat + 1 x 20m² Fire Varnish Overcoat (Interior)
- 20m² Pack (Exterior Spec.) = 3 x 20m² Fire Varnish Basecoat + 1 x 20m² Fire Varnish Overcoat (Exterior)
- Apply 3 coats of Thermoguard Fire Varnish Basecoat @ 20m² per 20m² pack/per coat
Followed by either;
- Internal Applications: 1 coat of Thermoguard Fire Varnish Overcoat (Interior) Matt or Satin @ 20m² per 20m² pack
- External, Damp or High Wear Applications: 2 coats Thermoguard Fire Varnish Overcoat (Exterior) Matt or Satin - Each 20m² pack is sufficient to apply 2 coats to 20m² of surface.
Please note: Timber must be clean and thoroughly dry prior to application (maximum 18% moisture content). Any gaps should be sealed with Thermoguard Intumescent Mastic. Fire should be prevented from accessing unprotected wood surfaces and for external applications it is recommended wood has been sealed on the reverse face (plus any other uncoated/vulnerable areas) to stop water ingress.
NOT suitable for the topside of floor surfaces that will be trafficked/walked on.
To achieve 30 and 60 minute protection minimum timber thicknesses apply of which approval must be sought before purchase.
For BS Class 1/0 & EN Class B s2 d0 ONLY see Thermoguard Fire Varnish BS Class 1/0 & EN Class B System
A gloss finish is available in batch quantities for large projects, contact us for details.
IMPORTANT - The below information from the manufacturer must be read and referred to your relevant authority for approval BEFORE purchase and use.
In line with good common practice, we recommend that approval be sought for the use of our system, outlining our justification for the issuing of the Fire Certificate prior to the product’s use.
Authorities generally accept our Fire Test evidence (copies available upon request) as justification for the provision of One Hour Fire Resistance in cases such as this for up to 1 Hour Fire Resistance, depending upon the thickness of board in question.
We have an indicative 30min Fire Test at a UKAS Fire Test Laboratory demonstrated 10mm loss to charring on plywood & MDF.
Our Fire Varnish BS EN Class B Test indicates that softwood did not burn significantly for the 20mins test duration and our previous Class O Part 6 Fire Propagation test indicates that protected softwood did not burn within the 10 minutes test duration.
Further in-house testing indicated that when applied at three times the Class B & Class O specification Fire Varnish intumescent added a total of 20 minutes Fire Resistance.
We assess projects requiring 30 or 60mins Fire Resistance on an individual basis, referring to the TRADA Char Rate Tables and calculated residual timber to ascertain whether we could issue a Fire Certificate for the project. A written specification should be obtained from the Technical Department for your project prior to use to ensure this system will be suitable.
In order to enable us to issue a 30 minutes Fire Certificate in the case of softwood the surface must be able to afford the loss of 10mm depth from all surfaces exposed to a fire. For 60 minutes we assess based on 25mm loss during the fire.
For oak or similar woods the loss to take into account is 7mm for 30mins and 18mm for 60mins.
In other words, the residual timber should be adequate to in the case of:
- Underside of a floor to support the anticipated weight load on the floor.
- A timber ceiling under-drawing a floor and joists can be treated as sacrificial but should have protected the area above to 30mins
- A timber wall should still be able to support itself without the fire passing through to the area the other side.
Timber must be clean and thoroughly dry prior to application (maximum 18% moisture content).
Important Application Notes
The Thermoguard Fire Varnish System should only be applied to clean, dry wood (maximum 18% moisture content), with dry conditions during application and drying of basecoat and overcoat.
Thermoguard Fire Varnish Basecoat is a water-based 2 pack coating.
Thermoguard Fire Varnish Overcoat (Interior or Exterior grade) should not be applied unless the basecoat is dry. Drying time of the basecoat in good conditions is overnight. Once the basecoat has dried in good conditions the basecoat remains ideal to overcoat for a further 4 days. Thereafter, the basecoat becomes gradually harder, until it reaches a point where the overcoat may not obtain a good bond.
Thermoguard therefore recommend overcoating when basecoat is dry, within the following 4 days in good conditions.
Delamination of overcoat caused by application to near-full cured basecoat has NEVER occurred when the overcoat was applied within 7 days. The longer the delay beyond '4 days after basecoat has dried' (so typically 5 days after application), the greater the risk of overcoat delaminating.
If overcoating is delayed notably beyond 7 days after the basecoat was dry, it is advised;
- Basecoat is abraded to obtain a key with 120 grit abrasive
- Apply a light coat of basecoat to replaced material removed during abrasion
- Apply overcoat within the ideal window or as near to it as possible
Application to OSB/Sterling Board
Only surface spread of flame protection can be provided to OSB, for BS Class 1/0 & EN Class B s2 d0 ONLY see Thermoguard Fire Varnish BS Class 1/0 & EN Class B System for details.
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. 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.