Selected generic NBS specification clauses covering, for timber, purpose-made joinery and preservative and fire retardant treatments. NBS Specification Clauses: Z - Building fabric reference specification
The first decision to be made regarding preservative treatment is whether the use of a naturally durable species will satisfy the durability requirements or whether treatment is needed. This Wood Information Sheet aims to guide the specifier through the process necessary to reach a decision that will result in a timber component that is fit for purpose.
Aspects considered include service factors, desired service life, the in-service environment, natural durability and regulated products.
Timber has been used for construction throughout history and the performance of timber out of doors is well understood. It has long been known that it is possible to extend the useful life of timber through good building/construction design and profiling wood components to shed water and thus dry down more quickly.
There has been considerable change in the regulations that govern the use of preservative treatments and hence also in the preservatives used. This Wood Information Sheet outlines the treatments in use today and their methods of application.