[Equest-users] Mixed construction roof

[Lars Fetzek]

Hello,
 
    The building that I am modeling consists of three floors.  Because the
3rd floor significantly differs from the 1st and 2nd floors in its shape and
size, I have modeled the 1st and 2nd floors as one shell (discussed in my
previous e-mail, titled "Disappearing components") and the 3rd floor as a
separate shell and project altogether.
    The present e-mail concerns the modeling of the 2nd floor roof.  The
portion of the modeled roof directly beneath the 3rd floor should be
adiabatic.  The remainder of the 2nd floor roof is constructed in various
ways with insulation of varying thickness and covered in some places by
deck, in other places by grass, in other places by nothing special, and in
some places by mechanical equipment.  Were this a simple shell, I would be
inclined to enter a single set of heat-transfer properties of the roof that
results from a manually calculated average of values weighted by area.
However, the 2nd floor includes several rooms and HVAC zones, each of which
is under a specific portion of the actual 2nd floor roof and/or under the
3rd floor.  Therefore, the simplification that I described above seems a bit
dicey.  Does anyone know of a way to properly model (in eQuest) a roof
comprised of such multiple constructions?
    Thank you in advance for any advice.
 
Lars Fetzek, EI
Phoenix Engineering Group
Tampa, Florida
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.onebuilding.org/pipermail/equest-users-onebuilding.org/attachments/20090716/ce6dcfd2/attachment.htm>