Kevin from Toronto writes
Timbor is a wood preservative that need to able to penetrate and be absorbed into the wood. If there is a stain, pain, or any type of sealant then the Timbor will not be able to penetrate thus making it ineffective. Any finish that has been applied to wood should be sanded off so that you can apply the Timbor for it to be effective. However, if you are wishing to restain the wood then BoraCare would be a better product because BoraCare dries completely clear whereas Timbor leaves a powdery white film.
Answer last updated on: 03/10/2015