SD or DD?

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Hello everyone I am new to eQUEST and have a question about what to use.

The building I am working on has 9 storeys and each single floor footprint is different.

The first three floors are part of a podium building and the rest is office.

In order to create different footprints and finish all the rest of the eQUEST inputs,

1) do I have to build a first floor on the SD wizard and finish all 40ish pages, AND THEN go to the DD wizard

creating new shells for the rest and new HVAC systems, or

2) do I just go the the SD wizard from the beginning to create all different building footprints?

Thank you for your help:)

Ju-Yeon Julie Shin's picture
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You may start directly in the DD wizard.

Also - You might be helped by reading Bruce's posts to me overnight about how to avoid getting errors with complex geometries.
Phantom errors are no fun.

Aaron Dahlstrom , PE, LEED(r) AP

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Ju-Yeon:

You need to be in the DD Wizard to create different floor footprints. The SD Wizard only allows a single footprint.

I would start in the SD Wizard, getting all of your window/wall roof constructions, general hours of operation, and system type (s). Not knowingwhat your zones will look like,?I would set?the zoning pattern to one zone per floor (for now).

Once this is set up, then change to DD Wizard to start creating your unique floors. Then you can uniquely set put your zones on a floor by floor basis.

Do you mean EVERY floor footprint is different from the others? This is a very unusual building.

John R. Aulbach, PE, CEM

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John (or anyone else),

If you have the time, would you mind explaining/suggesting the
efficiencies that might come from starting with SD, then converting to
the DD wizards? Every project I've ever performed has been DD from the
get-go, and when I have explored SD it appears to my untrained eye to be
a kind of linear, simplified version of the DD wizards....

To stick my neck out a bit - I fairly regularly have projects where we
start modeling at a stage when space zoning assignments and system
arrangements are quite fluid - it can be handy to define every space in
the wizard zone maps to allow for full flexibility later on, and this
often results in building a shell-per-floor, with each floor receiving a
unique zonal space layout.

I wouldn't dream of trying this approach on a high-rise building, but
with projects of up to 3-4 stories, things generally seem manageable.

To Ju-Yeon's situation (do understand I am one of the less-experienced
contributors here):

I would emphasize using as few footprints for your 9-story building as
is acceptable. I would start in the DD wizards, creating a shell for
each block of floors using the same footprint. I've read that you can
group your hi-rise shells in a way that simplifies things thermally
without losing accuracy.

For example, if you have three typical floor plans, and they were
ordered as such: (ground) A,B,A,B,C,C,B,B,B (roof) - I would suggest
building 3 shells as follows: [A,A],[C,C],[B,B,B,B,B]. In this way,
you at most need to define only three sets of everything to start, and
you're simultaneously ensuring the lowermost and highest floors, which
receive significantly different envelope loads, have the correct floor
plan tied to them. Remember the systems you define can ultimately be
tied to any combination of zones across different shells.

NICK CATON, E.I.T.

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Nick (and others):

Thinking it through, 99% of SD stuff is in DD Wizard. DD just allows you to make different floor (and/or building) footprints.

So I suppose you could start with a DD Wizard and leave it a single footprint, filling in the blanks with contiguous stuff, then making the different floor (or building) shells from there.

Wish?I had more time to speak. 7 models await my shaky hand.

John

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Thank you John, Nick, and Aaron for your help.

I have read Bruce's posts on complex geometries.

My building has very complex buildilng geometries with different footprints for each floor.

The building has void spaces on few floors and the facades are sloped. That is why it has different building footprints.

I am starting from the DD wizard as all you suggested to me. BUT I am worried whether these complex geometries give me a nearly accurate result.

Any comments on it?

Thank you again.

Jy-Yeon Julie Shin

Date: Tue, 15 Jun 2010 13:12:07 -0700

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Is this one of these 30th century looking skyscrapers being built in Shanghai, China? I saw a few renderings and physical models at the San francisco airport this week. I have NO idea how to model them..

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My last effort with a complex geometry turned out pretty good. You
need to do some work before you get going in eQuest. I only had 3
floors to do so working off 3 floor plans was enough to keep track of
the vertices's. You might consider a 3D wire frame in cad is things are
real complex and run both programs at the same time with the cad for
reference as you go. I added extra zones to my HVAC zones which lined
up with exterior walls in the floor above. This makes everything
removable later, ie the interior roofs which eQuest creates in the
model. For angled walls I would put them in square lined up at the
bottom floor, then tilt them over later and shorten the roof plane to
intersect. Voids are a little more tricky, I also created extra zones
to line up with the voids. One trick here is to enter the void zone
last. Put all the other zones around it first. This way all the walls
are attached to the other zones. The reason is you don't want any
orphan walls when you delete the void. You basically delete down to the
floor, exposing the interior roof on the floor below. I had planned to
leave the concrete floor on top of the roof, a minor thermo difference.
eQuest I thought does not allow you to delete floor areas. Once all the
surfaces are gone you can delete the zone and the floor area seems to
go, the roof will show in the 3D view. Then change all the interior
walls to exterior on the zones around the void. Add an exterior wall in
the same spot as the interior wall and delete the interior wall. Use
the location to place the exterior wall, look at the interior wall, get
the say, "V2 of the space polygon", select that in the exterior wall and
eQuest does all the geometry, pick you exterior wall type and you are
done, delete the interior wall.
Back to the trick. I learned the hard way here. One of my void
zones ended up with an orphan wall, ie the wall was attached to the zone
I wanted to delete not the zone which was to have the new exterior
wall. The surface of one zone is not called the same thing on the
adjacent zone. Also the geometry control point is different on every
zone. Every zone _has to be_ a closed surface. You can't leave the
orphan wall even though it is correct as far as location, type etc. It
looked perfect in 3D. To eQuest I had 2 zones with holes in them and it
wouldn't run. It took a lot of playing to make an exterior wall in the
other zone and get it in the right place. Once you get the plane
surface orientation right, you "just" adjust X,Y to pull it into place.
Make sure the azimuth is correct, the exterior of the wall has to face
the outside. "Just" was over an hour. Because there is no wall there
originally I don't think eQuest has a surface polygon set up in the
space to pick, that was my first try, just started picking polygons
looking for the correct one. It didn't seem to exist. If the wall is
highlighted in the component tree, you are in 3D, just click your left
mouse button on the 3D area and your wall will show up in red. Having
your vertices's on paper really helps here because you have to be exact
in the placement. To add to the complexity, everything is referenced
off the control point, you have to have it's location too. Long story
short, I finally copied the opposite wall, flipped the azimuth 180
degrees and pulled it into place. Once you change the azimuth
everything works backwards. It was in the wee hours of the morning, I
was not too sharp by then. This is an idealized version from foggy memory.
I added 2 screen shots, 2D, showing the void as eQuest shows it
after I deleted the zone, and 3D, showing the roof and my fun wall. I
did all the roofs as flat, there are actually 3 different cottage roofs,
2 which intersect, and about another 40% flat roof. Thermo wise the
flat roof should be conservative, my model will have a little more
heating and cooling than required but the occupants will be happy. A
little more is better than not enough. This building operates 24/7,
some fairly dense occupations in some of the zones, the heating and
cooling for the outside air dwarfs the roof loads. Put the zones back
together for the HVAC, interior walls for geometry can be made air
walls. Sounds simple, lol. Test each shell after you make it to make
sure the simulation will run, save a copy and do the next shell. You
can delete the covered roofs once you get the next shell on. The first
major step is to get the geometry right, default everything else. This
way you can keep going back into the building creation wizard without
losing any information or any time. You have to do this every time so
you can check the 3D view and your wall placements. Ignore the warning
eQuest gives you because you haven't put in anything to lose. Once page
2 of 25 is good, save another copy and work on pages 3 to 25. Before
you do the windows, save a working copy. You can lose a lot of time and
information in this area if you have to go back. Good luck.
Bruce Easterbrook P.Eng.

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Very nice Steven, my building could use some of this. You wouldn't have
the time to do a very rough concept highlight on the creation path would
you? A cad program and maybe some trig on the side would get the major
vertices. I can do a little unpaid learning on my creation off a way point.
Bruce

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