Modeling Roofs

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I am working on a very complex building where each floor is a different
shape and the floors get smaller as the building gets taller. This leads to
the need for many partial roofs. Is there an easy way to do this? The
geometry is rather complex and if there is a way to accomplish this in the
wizard I would love to know.

Also, does anyone know what the implication would be if I just put a roof
over the entire floor even though technically this is not the case?

Thanks in advance!

Susan F's picture
Joined: 2011-09-30
Reputation: 0


This problem is toward the top of my wish-list for eQUEST solutions. See
this previous post for some ideas:

Any exterior surfaces that you model (including roofs) will be treated
as though they are exposed to the outdoors, even if you put another
shell on top of, or next to them.


Bishop, Bill2's picture
Joined: 2011-09-30
Reputation: 0


Complex roof geometries can be defined with polygons, which is
especially helpful for visualization for verification of correctness (but
tedious). However, if the polygons are terribly complex, you might consider
simple rectangular roofs having the correct area as measured rather easily,
say, from AutoCAD files of the building plans. This should not adversely
affect roof heat transfer by pure conduction. However, I do not know
whether it will adversely affect roof heat transfer due to light absorption.
This depends upon eQuest's internal algorithm, to which someone more
knowledgeable must speak.

Lars Fetzek, EI

Lars Fetzek's picture
Joined: 2011-09-30
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Since eQuest treats any exterior surface as if were exposed to the outdoors,
then how should I compensate for the fact that I am building multiple shells
that are joined together side by side. Do I need to change the walls that
they share to adiabatic? Where do I do this in the Detailed Edit mode?


Kyle Nisonger

Nisonger, Kyle M NWK's picture
Joined: 2011-09-30
Reputation: 0


Adjacent interior zones separated by a wall may be modeled such that
that wall is an interior wall belonging to one of those spaces and "NEXT-TO"
(see the online DOE2-2 dictionary) the other space. If the two spaces
belong to a single zone, the inclusion of the wall is usually overkill. If
the two spaces belong to different shells altogether, no problem - just
include the wall as an interior wall. Do not create the wall twice (once in
each space). If both spaces are defined as having the same temperature, an
adiabatic wall should give identical thermal conduction results as a
rigorously modeled wall. However, the thermal capacity (related to the
specific heat and its ability for delayed storage and release of heat) of
any wall is affected by simplified/assumed parameters.
Eliminate any exterior wall bordering between these two spaces.
The creation of interior and exterior walls that do not span the entire
distance between vertices of the polygon defining a space or floor can be
accomplished by edits to the wall and/or the polygon (if any) that defines
that wall's shape.
See the online DOE2-2 dictionary for more info.
By the way - the same applies for ceiling/floor borders between spaces,
zones, and shells, since interior floors/ceilings are defined like interior
walls and roofs are defined like exterior walls.

Lars Fetzek, EI

Lars Fetzek's picture
Joined: 2011-09-30
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