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Hygric and Thermal Simulation

Free calculation tool for thermal mass (ISO 13786)

UPDATE: Please find a newer page on this topic here.

Finally I can provide the thermal-mass Excel-calculation tool, which I have promised for quite some time…  I hope this tool will help to get rid of all the simplified approaches suggested in the national standards and still used too much. I don’t think that these simplified calculation methods should be applied any longer as they produce flawed results. The precise thermal mass calculations involve multiplication of complex matrices, however this is no “rocket-science” and can be performed using standard excel spread-sheets.
I have therefore created a simple Excel-tool that does the maths for you.

Feel free to use and share it:

English version:
Thermal mass calculation tool according to EN ISO 13786
German version:
Berechnungstool Speicherwirksame Masse gemäß EN ISO 13786
Austrian version (contains ÖNORM definition):
Berechnungstool Speicherwirksame Masse gemäß EN ISO 13786 – ÖNORM B 8110-3

areal heat capacity, thermal mass, time lag, phase shift

Anyway, for more comprehensive studies I still recommend the use of HTflux instead of Excel… 😉

Related article:
» Thermal transmittance and dynamic performance (thermal mass) of a timber-frame wall

Author: DI Daniel Rüdisser, HTflux

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