Material properties/Functions

[Alberto Morales]

Hi,

I would like to know how would you define both hygrothemal functions and basic properties for glass, argon, interior & exterior tape around the window, sealant, diseccant silical gel, plastic/PVC or aluminium material for spacers, stell for metal studs and frame cavities (e.g., for jamb detail)?

I know that it is a lot but I hope you understand me.

Thanks in advance

[Johannes Amos]

Hi Alberto,



Materials like glass, plastic/PVC, aluminium have a high diffusion resistance and also no significant liquid transport. If you dont want to validate the water content in the material you could use a material like a vapor retarder, which has no liquid transport, and adjust the vapor resistance and the thermal properties. The same procedure can be made for window sealants.
For the glass and the frame of the window: If you do not want to validate dew water in between the glass of the window or in the window frame it can be a good solution to represent those materials as a solid block with no liquid transport. You then need to adjust the thermal properties according to the g-value of the glass or the Uf-value of the Frame.
For Materials like silica gel i have no proper solution, as they, in my understanding,
chemicaly react with water until they are saturated and only dry out again under higher temperatures.

I hope that answered your question.

Kind regards,
Johannes Amos

[Alberto Morales]

yes, you helped me but

where do you enter the g-value for galss?. maybe you meant the themal conductivity W/mK?

what do you mean with "validate dew water in between the glass of the window or in the window frame"?

[Johannes Amos]

Hi Alberto,

yes, sorry i meant you have to convert the Uw-value of the window. And what i meant with "validate dew water in between the glass of the window or in the window frame" is following: As for example your glass is only one solid block of one material after you converted it you cannot make a statement about the exact developement of the water content in the real construction. So if you simplify the component in this way, you should not evaluate the water content in this component.

Hope that helped.

Kind regards,
Johannes Amos

[Alberto Morales]

ok, as it is glass, it does not make sense to check water content or RH in there, is that what you mean (see area with a cross)? but I can assess water issues in the window frame or insulation around the window and surroundings areas (see tick area)?

[Johannes Amos]

If you simplify the frame this way, you can not access the moisture distribution in the component - only the the water content of the whole layer can be evaluated... Further you can assess the surrounding components. What material is your window frame made of?

[Alberto Morales]

hi Johannes,

Thanks for your help but I do not understad what you mean.

the material is hardwood