There are two aspects to the durability of glulam in the weather - the durability (rot resistance) of the timber species, and the suitability of the adhesive. Timbers of low natural durability, such as pine, must be preservative treated in accordance with Australian/New Zealand Standard 1604, Specification for preservative treatment, Part 5: Glued laminated timber products. Alternatively, the beams can be made from naturally durable species. These factors are explained in more detail in Technical Data Sheet No. 2 of the Glued Laminated Timber Association of Australia (GLTAA), available for download via this link https://gltaa.com.au/architectural-engineering-design. A recent inspection of weather-exposed treated pine glulam members in the National Wine Centre showed that they had retained their integrity after 20 years' exposure with relatively minor checking. We consider you can specify glulam with confidence if the GLTAA guidelines are followed.Glulam
Answered on 02-03-2021
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