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I am looking for precise section sizes of your 163 x 30 LOSP double rebated door jamb


I have a client looking to use CLT both in Sydney(Aus) and in London (UK).
Where could I find tables that provide the thermal resistance for CLT with certain thickness?
For the UK they require U-values and Sydney requires R-values.

Woodsolutions Answer +

Thermal properties of timber depend on the type of timber, its moisture content, and its thickness. In Australia CLT is made from pine. According to CSIRO data the R-value of pine at 12% moisture content is 0.01 m2.K/W per millimetre thickness. So 100 mm of pine CLT would have an R-value of 1.0. R-values are derived by thickness/lambda. European producer Stora Enso quotes a lambda value, or k-value, of 0.13 W/mK for their CLT. So the R-value of Stora Enso’s CLT would be 0.001/0.13 = 0.008 per millimetre thickness, or 0.8 for 100mm which is slightly lower than CSIRO’s data. U-values are the reciprocal of R-values, ie. 1/0.8 = 1.25 for 100 mm CLT. The calculation of thermal values is explained clearly here: Beware of US data which is expressed in British Thermal Units (BTU’s) and therefore the numbers are quite different.

CLT Thermal Values

We are looking to use a timber portal frame for a building we are currently designing. The building is quite simple, rectangular with metal sheet cladding. The portals are required to offer a clear span of 25m. Can you please advise what a rough lead time may be for such a product, and additionally could you provide some advice or reference to the fire resistance properties of these sort of portal frame products?

Woodsolutions Answer +

You will have to contact a company that produces timber portal frames to discuss lead times, for example Timberbuilt Solutions could advise you. They have a website here: Regarding fire resistance, this can be calculated by reference to Australian Standard 1720, ‘Timber Structures’, Part 4: Fire resistance for structural adequacy of timber members. Possibly Timberbuilt can also advise on this point.

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