WUFI

Hello All

I am modelling the thermal upgrade of a flat ceiling, to a large attic space above. Does anyone have any references or thoughts on modelling the external condition on the ceiling i.e. the attic? Simply adding a surface resistance does not account for the extremely high temperatures and humidity that that can occur in these spaces

Any thoughts welcome!

Hi sfenton,

simplest way would be to use outdoor climate with a temperature shift.
We performed research on this topic some time ago, but this is only published in German up to now. There a model for non-ventilated attics was developed.

Nebenraum-Klimamodell für unbeheizte Dachräume: https://wufi.de/de/wp-content/uploads/sites/9/555.pdf
Energieoptimiertes Bauen Klima- und Oberflächenübergangsbedingungen für die hygrothermische Bauteilsimulation: https://wufi.de/literatur/Zirkelbach,%2 ... gungen.pdf

Christian