Ronseal total wood preserver is a general purpose preserver that has been specially formulated to kill woodworm and prevent rot and decay it is an ideal pre treatment for interior and exterior wood and suitable for overpainting perfect to use on rough or smooth timber coloured preservers are made for outdoors and will colour and protect in all weather the clear wood preserver does not waterproof and is made for preserving indoor wood before you start ensure all surfaces are clean dry and free fr