Performance: Timber treatment

Highest quality slow grown timber combined with double vacuum preservation treatment give the ideal foundation for timber finishes.

All NorDan products are protected from rot, fungal attack in accordance with European standard NS EN 351-1 class NP3. Antifungal preservative treatment is colourless and harmless to humans.

Application
After assembly of sash and frame, with all joints glued and dried, the frames are first sealed into air-tight vacuum tanks. A vacuum pressure of approximately 1kg/cm2 is created which draws the air out of the grain, causing the timber to 'shrink'. With the vacuum held, the tank is filled with preservative which is absorbed by the timber. The tank is then pressurised for a short time to encourage maximum preservative penetration of the timber. A further vacuum pressure is finally applied to draw any excessive preservative from the timber. The frames are then removed from the tank and allowed to dry naturally before returning to the production lines.