Copper Naphthenate (CN) is a heavy-duty product that offers extra preservation protection. CN products come in two forms: an oil, and an emulsion.

CN products are often used where the treatment seal of the timber has been broken (e.g., a piece of timber has been cut). By applying a CN product to the cut end, this will ensure that the product continues to be protected from rot and wood borers.

The end grain of exposed timber sections, such as the top of posts, or end of exposed rails, should also be treated with a CN oil. When exposed to weather and sunlight, the end grain will dry out and start cracking/splitting. The CN products will increase water repellence, which will slow down the cracking and splitting.

CN Oil – CN oil is a clear product, and can be easily applied with a paint brush, roller, broom, etc.

CN Emulsion – CN emulsion is coloured green and has the consistency of grease or paste. It can easily be applied to the timber with a spatula or paint brush.