# Tilted roof?

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Is there a way in the eQuest DD Wizard to make a full tilted roof? I
know there is a way to make a pitched roof, but that seems more geared
towards residential applications as they don't give you much flexibility
in tailoring it to your custom project. I'm sure there is a way in the
Detailed Edit mode but in my first few attempts at that all my polygons
went crazy. This is the type of tilted roof I want to model (section
view) that is tilted on the south orientation for PV panels:

Any help would be great...thanks.

Josh Greenfield, PE, REP, LEED AP

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Joined: 2011-02-17
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Josh,

I know that you are asking about the DD wizard. Unfortunately, I gave
up on wizards long enough ago to have forgotten their specifics.
For what it is worth, I will supply this answer concerning the detailed
mode: Define your exterior walls on the left and right of your shown
cross-section as exterior walls and use the "height" parameter to set their
heights independently of the floor height. Define whatever exterior walls
(if any) that would be parallel to the computer screen surface that shows
your cross-section as exterior walls referencing polygons. Define the roof
as an exterior wall and use the "tilt" parameter to make it tilted. For all
elements, check out the "azimuth" parameter to ensure proper rotation in
plan view.
I suggest a mix of trial-and-error and doing good 'ol high school
trigonometry by hand on paper until it all works out. Tedious, I know. But
after alot of struggle doing things the "user-friendly" way, I have found
this approach easier.
By the way, good info on all of these parameters can be found using the
help by right-clicking on the parameter fields ("height", etc.) and/or by
finding the DOD2-2 dictionary online.
Good luck!

Lars Fetzek, EI

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Joined: 2011-09-30
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In order to make a tilted roof in DD mode, change the tilt angle of the
roof surface. Depending on the vectors used to define the polygon and
surface, the axis of tilt may be right or wrong. If it is wrong, try the
following steps:

1) create a copy of the polygon used to define the roof surface

2) change the azimuth of the roof surface

3) modify signs (-/+) and invert x and y components of new polygon
in order to relocate roof

4) Note the distance from the axis of rotation of the building
origin and the desired axis of rotation on the roof surface and use this
displacement to reposition the roof. Delta elevation will be SIN of the
tilt angle times this displacement. The lateral displacement will be
(1-COS of the tilt angle) times the displacement.

Once the tilted roof surface is created, new triangular external wall
sections can be created to fill in the gaps. I apologize if this
explanation is unclear.

-Ryan

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Joined: 2011-09-30
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