No coating is required to counteract leaching> Durability
The timber/panels treated with fire retardant, Burnblock®, by Lemahieu Fire Protection® don't require a coating in order to counteract leaching.
The durability of the treatment over time is guaranteed without coating for external applications.
The durability over time is guaranteed and document without the use of a protective coating.
For this purpose, tests are being carried out in accordance with EN927-6, one of the three test options within the new BS EN16755:2017 standard. The test comprises an accelerated weathering process with UV and the equivalent of over 120 years of rain in Belgium.
The tests are carried out on ThermoWood® pine and Western Red Cedar and both retained reaction to fire class B, both before and after accelerated ageing, in accordance with test method ISO 5560-1: 2015.
The following applies to the durability of timber products treated with Burnblock® fire retardant using a vacuum/pressure:
The effect of the fire retardant characteristics decreases at a speed equal to the degradation/ageing of the timber itself.
This means that the effective level of fire retardant per unit of timber remains unchanged, thus allowing Burnblock® to retain the reaction to fire class B.
If another type of fire retardant coating is selected that does require a protective coating against leaching, this coating will have to be newly applied on a regular basis (about every 5 to 10 years). It speaks for itself that the necessary budget will need to be provided over the lifetime of the building.
© copyright picture: architect www.crahayjamaigne.com | Project ‘passive zero-energy certified’ office building, Ovifat. Façade cladding in Cedar, treated with fire retardant by Lemahieu Fire Protection® with Burnblock® up to B-s2,d0.
Do you wish to receive more information or advice concerning the reaction to fire classes, don't hesitate to contact our Technical sales advisor.