QUESTION:

I have noticed that if I click the Calculate Thermal Properties button in the Layers Tab of the Material Library the U-value is updated and is usually much higher than the ones defined in the Material Library (this happens even with default ECOTECT materials). Does ECOTECT use the U-value given by the user, or does it calculate the thermal properties of the material, regardless of what we define in the U-value cell, it the Properties tab ?

ANSWER:

ECOTECT always uses the value in the U-value entry in the Properties tab.

The "Calculate Thermal Properties" function is just there in case you cannot find data for a particular material construction and you need to construct it of composite layers. When using this option ECOTECT is calculating the U-valued from the specific heat, density etc. as defined in the Layers tab ...so you must bear in mind that this is just an algorithmic approach and is not always ideal. So if you have recorded or referenced material data we always recommend that you use that in preference to calculating a U-value from within ECOTECT.