Treatment Service
Timber is vulnerable to attack from insects, damp and fungi and needs protection from all of these to extend its working life. All Imprest products are treated using a vacuum-pressure-vacuum method and we also offer timber treatment as a separate service.
Preservatives and Hazard Classes
We have 2 treatment tanks and water-borne, chromiumfree wood preservative – Impralit®-KDS. Please click here to read more about Impralit®-KDS. Chemical is safe for the environment and give the necessary protection depending on the hazard class. For different products, markets & customers we are using different treatment processes but the majority of our timber is being treated according to European Standard EN 351-1 to meet the following hazard classes:
- HC2 – for outside undercover usage
- HC3 – for outside non ground contact usage
- HC4 – for outside in ground usage.
According to NTR (Nordic Wood Preservation Council):
- NTR AB - for outside non ground contact usage.
- NTR A - for outside in ground usage.
During the summertime untreated products are being treated with anti-stain preservative by dipping in order to avoid bluestain & mould.
Treatment is available in three colours:
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Green ("Park Green"), HC4, HC3, NTR A, NTR AB
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Brown ("Evening Brown"), HC4, HC3, NTR A, (NTR AB?)
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Grey ("Vintage Grey") HC3
For extra information you can read about our treatment quality and certificates.