What is hc4 timber treatment?

UC4 15yr desired service life - timber treated to last when used in ground contact. Sometimes referred to as HC4, Use Class 4 or "UC4" is the standard of treatment required for timber which will be used directly in the ground as determined by BS EN 335-1.

The preservative in UC4 treated timber is the same, but the process prior to treatment is changed to enable more of the treatment to penetrate

Hazard Class 4 (HC4) fence posts are available to buy online from to find traditional 'Crossing Timbers' with in particular Treated Softwood

Posts. In my experience of tantalised and protimised timbers the amount of visible penetration can vary . If the timber has been recently treated"7 posts" ·" I bought two posts rated as HC4. When they were cut I was concerned to see a big difference

In order to extend the service life of timber, products are treated with impralit®-KDS (HC3, HC4) and Embalit (HC3) wood preservatives. The preservative

Shop our latest treated Timber Post 175mm x 175mm HC4 at a great price from Challenge Fencing in Surrey, Kent and Gloucester."Starting from £91.22

Rough sawn posts for fencing and other garden projects. Pressure treated green (natural) colour. Available in a range of heights and sizes. Rough sawn timber.

TREATED TIMBER AT COMPETITIVE PRICES IN CASTLEWELLAN · Timber treatment · Uc4/HC4 Treated.