Woodsafe Exterior WFX™
Woodsafe Exterior WFX™ is a unique fire impregnation system for wood products that is based on polymer technology, which means that the fire protection agent hardens and forms a waterproof polymer. The result is that wooden cladding can be exposed in an exterior environment without requiring surface treatment for natural ageing.
Aging process on nature's terms
Woodsafe Exterior WFX™ fire retardant treatment is available in several different types of wood, including red and yellow Cedar, shingles of Cedar, Thermowood Spruce, -Pine, Ash, Accoya, Nobelwood, Ayous, Frake, Spruce, Core pine, Larch and more.
Woodsafe Exterior WFX™ fire retardant manufacturing is covered by a type approval certificate according to the Swedish Housing Agency's building regulations, Plan and Building Act (SFS 2010:900) and construction product regulation 305/2011, EN14915 with associated continuous manufacturing control by RISE (0402). Document reference TG0263-08, CPR-0402-SC0260-15.
Woodsafe Exterior WFX™ fire retardant treatment is the only FR-product on the market certified according to EN16755 EXT and ASTM D2898, which is directly decisive for the suitability of installing fire-impregnated wood in an exterior environment without a protective paint layer, making the product an excellent choice for facade cladding to age naturally without maintenance . It is important to know that the English variant BS-EN16755 EXT, which is not approved by the CEN commission, cannot be compared with EN16755EXT.
Technical characteristics
Technical characteristics
- Reaction to fire: B-s1,d0. (-s2)
- Facade cladding: SP-Fire 105
- Utility class EN16755 INT1, INT2, EXT
- LR-resistance (Leach resistance, Wood Protection Association, UK)
- Approved facade cladding* with Rockwool, Isover, Kooltherm, Finnfoam
- Approved facade cladding* with KL wood substrate, D substrate, 3-layer board (D), Spruce plywood
- Meets the requirements for E1 (EN717)
*Contact us for more information
General information
General information
In our impregnation process, the wood and the wood product are wetted in their entirety, and depending on the product, 2-15% by weight of fire retardant is pressed deep into the cell structure of the wood, where it is fixed.
The combination of moisture and drying means that an initially finished planed, sawn or processed wood product can become slightly crooked and warped compared to untreated wood. The better the quality of the wood product, the better the final product.
In the fire impregnation process, the wood is soaked with water mixed with fire impregnation agent, and then dried. The impregnation process also means that dimensional changes depending on the type of wood and plywood can occur, even within the framework of the same quality grading, which can result in the wood material's dimensions changing differently.
Dimensional change may deviate from planing tolerance and plywood tolerance, which is considered ok because the impregnation process takes place after planing and the production of plywood. It is the responsibility of the client/customer to take these conditions into account when ordering Woodsafe's contractor impregnation services through partners.
Woodsafe Exterior WFX™
The market's No. 1 fire retardant impregnation for exterior "Durable Fire Protection" natural aging
Sample projects Woodsafe Exterior WFX™

Botanikern
One of Uppsala's first apartment buildings with a wooden frame, which won the city's architecture award 2020. Thermowood fire-impregnated with Woodsafe Exterior WFX™.

Universeum Gothenburg
Sweden's national science center, world-unique visualization lab and visualization court. Cedar shavings impregnated with Woodsafe Exterior WFX™.

Cederhusen Stockholm
One of the world's largest wooden house projects in an inner-city environment, which won construction of the year 2022. Cedar shavings (red/yellow) fire-impregnated with Woodsafe Exterior WFX™.

Sergelhuset Stockholm
Unique remodeling/renovation project awarded LEED Building/Project of the Year 2020. Cedar shavings impregnated with Woodsafe Exterior WFX™.
FAQ Woodsafe Exterior WFX™
Is Woodsafe Exterior WFX™ organic fire protection?
No. Worth mentioning is that there are no fire retardants that are organic. Claims of natural and organic fire retardant are a marketing strategy that sounds good, but it is not true.
Is Woodsafe Exterior WFX™ toxic?
No, the product is not classified as hazardous to health or the environment.
Can Woodsafe Exterior WFX™ be used indoors?
Yes, but it is mainly used in environments with very high humidity.
Can Woodsafe Exterior WFX™ be surface treated?
Yes, but only in the factory with a special tinting system. Tinting means that the product can be colored in a thin layer, such as transparent lasering in several shades, for example green, silver, grey, black, sooty black, brown and driftwood. Cover painting is not recommended, nor is surface treatment in the workplace due to adhesion problems with standard products.
Does Woodsafe Exterior WFX™ contain substances included in the REACH CLP list?
Yes. In the concentrate and process liquid there is formaldehyde, which is classified Muta. 2; H341 and Carc. 1B; H350.In the fixing process, the fire retardant is hardened into a stable polymer where the levels are below the limit level for emission E1 (EN717).
Can I treat with silicon such as Organowood, Sioox, iron vitriol?
No. The treatment does not provide the effect that the supplier markets, such as gray tinting or water repellency. The wood naturally turns gray over time, in any case when it is broken down by UV light and more.
Can fire retardants based on iron phosphate, di-ammonium, ammonium phosphate be compared to WFX's maintenance-free properties?
No, that is not possible. They are completely different types of composition chemicals, where function and properties cannot replace or equate as equivalent to Woodsafe Exterior WFX.
Is Woodsafe Exterior WFX™ type-approved?
Yes, since 2018. Included in type approval certificate. Ref. no: 0263-08. Approved properties are SP-Fire 105, EN16755 INT1, INT2 and EXT.
Is Woodsafe Exterior WFX™ CE certified?
Yes, since 2015. CE certificate no: 0402-CPR-SC0260-15 (EN14915:2013).
Can I buy the product directly from you?
No, we sell through partners who are more than happy to help you. Click here to get to resellers.
Does Woodsafe Exterior WFX™ have fire resistant properties?
Yes, it is suitability tested and approved according to EN16755 INT1, INT2, EXT. The properties are verified by RISE in type approval certificate TG0263-08.
DoesWoodsafe Exterior WFX™ contain hygroscopic substances such as ammonium phosphate?
No.
What sets Woodsafe Exterior WFX™ apart from other fire retardants?
Woodsafe Exterior WFX™ is a multi-component fire retardant that in the process hardens into a long-lasting stable polymer (a bit like 2-component glue, put simply). In comparison with other fire retardants based on hygroscopic easily soluble substances, such as di-ammonium, monoammonium, ammonium, iron (III) phosphate, urea, polyammonium phosphate, which cannot be used without an approved surface treatment in, for example, an exterior environment. Exterior WFX™ is the only approved exterior fire-impregnated wood product with no requirements for surface treatment according to EN16755 EXT and American standard ASTM D2898.
Some operators claim that their product is maintenance-free because the type of wood is impregnated, is that correct?
No, through impregnation in relation to the properties of the fire retardant are two completely different things. Claims that fire retardants containing ammonium have equivalent properties to Woodsafe Exterior WFX™ are completely unfounded.
In addition, many types of wood cannot be impregnated as it is claimed. Types of wood such as spruce, larch, cedar and oak are some examples of types of wood that cannot be impregnated through, as a fire protection impregnation.