Attic Space

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Hi there,
I'm trying to model a small commercial building with vaulted ceilings,
and can't figure out where to specify this. One help screen says:

*"Top Floor Ceiling Finish* is only available if a Top Floor Attic has
been specified on the Building Footprint screen. Top Floor Attic is
currently available only for multifamily building types."

I don't see where to uncheck this option though.

Anybody done a vaulted ceiling before with no attic space?

Thanks,

--
Dane Heimerman

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Dane,

Here are two ways you can model a space with a vaulted ceiling.
In the wizard, Bldg Envelope & Loads, Screen 2, set Flr-To-Ceil height
equal to Flr-To-Flr height, so that no ceiling plenum is created. On the
same screen, check the "pitched roof" box. An "Under Roof" space will be
created and assigned to the top floor of the building. Unfortunately,
you can't tell eQUEST to combine the Under Roof space with the space(s)
below it. There will be "UnderRf" surfaces assigned to the spaces below
the Under Roof space. These act like horizontal ceiling surfaces. Once
you switch to DD Edit mode, you can do one of these options:
1.) You can change these UnderRf surfaces to Air Walls to enhance
conduction. If you just delete them, you remove any conduction between
the Under Roof space and the spaces below it, which might be acceptable
if you do option 2.)
2.) You can additionally, or optionally, assign the roof surfaces of
the Under Roof space to the space(s) below it. This may require
adjusting the X,Y and Z coordinates of the roof surfaces.
I usually do option 1. There may be an advantage to option 2 that is not
occurring to me. I don't know which one would be more thermally
accurate, especially considering that eQUEST does not model thermal
stratification.

Regards,
Bill

William Bishop, PE, BEMP, LEED(r) AP

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