Wood Preservation in Canada.

Abstract

The same fungi, bacteria, and insects which preserve the biological cycle of the forest cause damages in building wood which amount to $90 million a year. Fungi are the principal agents of decay. The two types of products which were perfected in Canada for combating fungi in wood are soluble in water or soluble in oil. Creosote which is the foremost oil soluble product for preservation was replaced by water soluble agents like chromated copper arsenate (CCA). Several methods have been found for applying preservatives: brushing, immersion, thermal treatments, pressure, liquified gas. No preservation product can penetrate logs of sawed wood completely. The preservative forms an envelope which protects the heart of the wood. The cost of wood and handwork encourage the use of wood preservatives to lessen maintenance. Construction problems, regional differences, energy saving, and new techniques make these products more in demand. LB - G4 LB - Wood