R Value in USA Vs Australia?

[jason]

Hi there,

Can someone tell me the difference of the R value in USA and Australia?

[ktkhor]

Hi Jason,

R Value is a measure thermal resistance utilisng by the building industries for insulation purposes. The major difference of R Value in USA and Australia is USA is using the emperial method and compare to Australia that applying metric for the R-Value.

R-Value is normally converted from the thermal conductivity (K-Value) watts per metre per kelvin.
The lower the thermal conductivity, higher the thermal resistance (R Value).

To convert imperial USA R value into metric value, here is the example,

USA R Value X 0.176 = Metric R Value

e.g
Conisder lexan sheet with U value of 0.52 for its 10mm thickness
Convert to R value 1/0.52 = 1.92 R Value in Imperial (U Value is inverse of R Value).
and Multiply 1.92 X 0.176 = 0.34 R (metric).

Hope that help to solve your doubts.Cheers!

p/s: Appreciation to Mr Nigel Legge for his kind assistance with this answer.