In our knowledge center you will find answers to frequently asked questions. This is also a place for useful downloads, such as certificates and test reports.
Can’t find the answer to your question here? Then please contact us via the contact form.
Of course we find it important to provide a guarantee that our fire-retardant treatment is safe and nature-friendly. View our certificates here.
Download useful information sheets from Hestus here.
In case of a risk of fire spread, strict requirements apply to the speed at which fire may spread across the façade. According to the NEN 6068 standard (fire spread calculations), at least 95% of the façade must comply with fire class B to prevent rapid fire spread. Façade openings are an exception and must meet at least fire class D.
For a complete overview of the required fire classes, consult table 1 in our whitepaper Test method and application.
Fire safety requirements often apply not only to individual materials, but to the entire construction, such as an exterior wall. It is not self-evident that separate materials that meet the requirements will also guarantee the same fire safety in combination. To demonstrate this, you can have a fire safety specialist provide substantiation or carry out a test: the so-called SBI test (in an end-use application). In this test the entire façade construction is tested, instead of only the outer cladding.
The wood fire-retardant treated by Hestus may only be processed under specific conditions to ensure that it continues to comply with fire class B. These conditions are based on the results of fire tests and the test setups used. If the wood is not applied according to these guidelines, the validity of the fire class lapses.
For an overview of the application conditions and limitations, consult table 3 in our whitepaper Test method and application, which includes the Field of Application matrix.
Hestus can fire-retardant treat various standard wood profiles. Based on available tests and reports it has been determined which profiles are suitable for application. Consult table 2, ‘Standard profiles’, in the whitepaper Test method and application for more information.
The wood species fire-retardant treated by Hestus have been tested and comply with fire class B. During these tests, carried out according to the so-called SBI method, a standard configuration was used: a non-combustible substructure (class A1/A2), a wooden framework (fire class D), and wood treated with BurnBlock®. This configuration serves as a reference for applying the material to façades. Would you like to know more about this? Then read our whitepaper.
You can also buy fire-retardant wood at Hestus. We do this in cooperation with sustainable partners.
We are happy to receive the order via the contact form.
For a quotation you can easily request an offer.
The cost of fire-retardant treating wood depends on the wood species and the quantity. By requesting a quotation you will receive a price indication of the treatment.
BurnBlock® is a nature-friendly, highly effective and non-toxic fire-retardant. The powder consists only of natural substances and is completely safe for humans, animals and nature. BurnBlock® powder prevents oxygen from reaching the treated material. And without oxygen, there is no fire.
Would you like to know more about the active ingredient of our fire-retardant treatment, then see: BurnBlock®.
No, the active ingredient of our fire-retardant treatment is BurnBlock powder. This product consists of 100% natural ingredients and causes no harm to humans, animals and nature. The product has the Cradle to Cradle Gold® certificate and is the most sustainable option on the market.
The fire-retardant treatment by Hestus does not discolor the wood*. Because the fire-retardant penetrates into the fibers of the wood, there is optically no or very little difference compared to untreated wood. It is possible, however, that due to the fire-retardant treatment the weathering of the wood occurs somewhat later than with wood parts that have not been fire-retardant treated. It is recommended to take this into account during the design process.
*Wood is a natural product and may naturally have color variations.
With the fire-retardant treatment of Hestus the wood reaches B-s1, d0. In case of fire this means that it is very difficult to ignite, produces little smoke, and no burning parts are produced.
Building materials are classified into Euro fire classes to indicate their fire safety. This is always indicated with a combination of letters and numbers. The first letter describes the combustibility of a material.
Fire class A1: Non-combustible
Fire class A2: Practically non-combustible
Fire class B: Very difficult to ignite
Fire class C: Combustible
Fire class D: Easily combustible
Fire class E: Highly combustible
Fire class F: Not tested or does not meet class E
The letter s describes the smoke production of the material. It is divided into 3 categories.
S1: Little smoke production
S2: Moderate smoke production
S3: High smoke production
The letter d (Droplet) indicates the burning droplets and parts that occur in case of fire. These form a direct danger to people and can cause possible new fire outbreaks elsewhere.
D0: No production of burning parts
D1: Parts burn shorter than 10 seconds
D2: Parts burn longer than 10 seconds
The treated wood that comes out of the process contains a lot of moisture. Rapid changes in temperature can cause moisture to leach out quickly or slowly. That is why the wood is gradually dried in a drying chamber, allowing the treatment to penetrate the wood properly. The drying takes an average of two weeks.
