There is a specially designed 4-way chamfered notch-joint system ensuring a tight fit to all boards with no room for damp or wind penetration.
We apply Wood preserved Cuprinol - Cuprinol Wood Preserver Clear gives deep penetrating protection to outdoor wood. It is specially formulated to protect against rot and decay and also contains water repellents to help resist rain penetration. The unit is then coloured for further protection.
Therefore, the unit would only need a top up coat every year or so to maintain that new look.