Fills and Area Calculations

[Anonymous]

Newbie here. I need to calculate the area of wall exposed on the exterior of a building for the IECC. I have rooms that are 2 stories, and they are bordered by rooms that are one story, so the area of the wall actually exposed to the exterior is somewhat complicated. Perhaps there is another way to do this, but I'm overlaying the exposed portions of the walls with a fill pattern, which gives me the area very nicely. However, I want to subtract out the areas of openings in order to come up with a net number and a gross number for exposed wall area. I have a couple of circular windows, and a couple of other arched windows. I can use the "subtract" feature of the pet palette, but I don't get a pet palette with the circle/arc feature. Is there a way to subtract circular areas from fills?

[Anonymous]

Hi Larry,

Draw the outline of the window using a 2d circle. You can then use the magic wand to remove this area from the fill.

To do this, first select the fill, activate the fill tool, hold down the space bar to turn on the magic wand, then either left click the edge or inside the circle to remove that area.

You may need to use the draworder buttons to bring the 2d lines and fills to the front.

This technique can also be used to create any circular geometry you need by drawing a 2d circle and magic wanding it.

Hope that helps!

[Erika Epstein]

Ideally, you could create a schedule that will give you this figure. Create a schedule of walls as shown. I created a building 10'x10' with walls 10' high

The left column gives the gross area of the walls on the reference line side as I put the reference lines of the exterior walls on the outside face of the wall. If your ref lines are on the inside face of the exterior walls, then call that parameter in your schedule.
The middle column gives the area of the openings. Note windows are shown unit size as desired, the door area unfortunately by default the r.o., probably not what you want, but I include to show schedule limitations.

The right column shows the net wall area (gross less wall openings). You could easily correct the door areas and quickly get the real net area of the exterior walls.
The advantage to the schedule is this is live i.e. it will update with the development of your design.

There are other discussions here about the problems with the R.O. v.Unit Size i.e. inconsistencies in the Interactive Schedule

[Anonymous]

Many thanks, folks.
Larry