Fire retardant technologies

How does timber become fire-retardant?


Timber iturns into a fire-retardant material either from the inside (block treatment) or from the surface (coating treatment).

The former is conducted through a vacuum-pressured autoclave and leaves high quantity of fire retardant agent inside the piece of wood without changing its aspect after kiln-drying (a slight yellowish shade is expected though, due to the oxydation of the surface). It's a stand-alone procedure if timber is to be set indoor, no further operation needed, unless for aestetics or architectural requirements.

The latter is made by applying a two-product coating system called intumescent varnish (or intumescent paint). Each potentially-exposed side of the piece shall be coated. The intumescent varnish acts like a shield when submited to a rise of temperature by transforming itself into a protective shell which doesn't allow fire to reach the piece of wood. This technique has a double advantage of protecting timbers from fire and giving a neat water spillproof finish.

Woodenha is the expert of both techniques and provide such services to their clients.



How timber should be stacked before impregnation?


Whether it is for fire-retardant impregnation or for kiln drying, stacking is a highly important operation which contributes to the quality and succes of those to processes. Woodenha acquired skills for that matter, adapting the stacking to the kind of wood, its shape, its thickness and its purpose. Unless specifically required by the client, stacking is included in the services of Woodenha by default.


Need a tip for your project or a quote?

Get in touch with an expert team member for any query about fire retardant treatment, intumescent coating or kiln drying for timber and panelboards.

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Any question? Have a look at our FAQ first!

In this section, you will find the answers to the main questions we've been asked: regulations, industrial process, do's and don'ts etc.. It's all there (almost)

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Lost in the fireproof wood jargon?

We've thought that you might need help to understand perfectly the fire retardant treatment subtleties... Here's our lexicon.

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