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Insulate between zones?

Posted: Tue Jun 30, 2015 5:16 am -1100
by ChrisBriley
I'm working on a retrofit project. I have 3 zones. Zones 1 and 2 are livable space with normal temperature settings and insulation. Zone 2 occupies half of the basement. It will be fully insulated and have normal temperature settings (68-77 degrees F). Zone 3 is the other half of the existing basement that is part of interior envelope, but will be unoccupied (just used for mechanicas and storage). The plan is to insulate the walls between zone 2 and 3. When I select a wall between zones 2 and 3, the tabs for "General", "Assembly", and "Surface" disappear. I'm assuming this is because this is an "interior wall"? It makes me question my approach to modeling this home this way. How does one accurately model this scenario?

I'm using WUFI Passive 3.0 (I have WUFI Plus if I need to use it on this)

thanks.

Chris

Re: Insulate between zones?

Posted: Wed Jul 01, 2015 3:40 am -1100
by ChrisBriley
I think I've figured it out on my own. I'm going to use that basement space (zone 3) as an "Attached Zone" with a temperature reduction factor. Of course the reality is that this is not truly an "unheated, unconditioned space". And this feels like an inaccurate solution, so I'm still open to suggestions.

Chris

Re: Insulate between zones?

Posted: Wed Jul 01, 2015 10:01 pm -1100
by mpazold
I think for the passive house verification, the attached zone is the usual way to handle zones which are not within the occupied space, respectively within the thermal envelope. Different design conditions for different zones and furthermore a multizone calculation for such cases is not used so far. The heating, or cooling demand of attached zones is not calculated. You reduce the temperature difference between inner and outer climate with the temperature reduction factor for the heat loss via components between conditioned zones and attached zones. But you don't heat or cool the attached zone, so there is no demand for that.

The hourly dynamic simulation with WUFI Passive, of WUFI Plus can handle differnt design conditions for different zones. For further investigatations like this you can switch the type of zone 3 to a simlated zone and, for example, simulate a free floating climate wihtin it, if you set zero coverage from the hvac system for that zone, or you can use another system, or add small internal loads for that zone...