Creating the building envelope from my masses took way longer than I anticipated, but I’m quite pleased with the current result! The main difficulty I had was creating curtain walls for the building’s “stem”, which is both a curved and inclined surface. After many issues with self-intersecting lines, I was able to eventually re-make the profiles for the tops and bottoms of the stem so that the exterior wall edges were aligned from top to bottom, despite the inward slope.

I think it looks pretty slick with the “realistic” color setting. The “consistent colors” setting is shown beneath it for comparison.

Building Envelope

I did my best to make the walls, floors, and roofing extremely insulated. I want this building to require as little energy as possible for thermoregulation, especially given how much of its surface area is taken up by windows!

Interior Wall (with 6” of rigid insulation):

Exterior Wall (with 1’ of rigid insulation):

Flooring (with 1’ of rigid insulation):

Green Roof (with 1’ of earth and 6” of rigid insulation):

For the curtain wall panels, I selected 1/8” triple glazing with low E:

I was unable to modify the material composition of my revolving doors for some reason. Its thermal properties were greyed out, but when I selected “user defined”, it automatically populated with these values:

My building has no dedicated shading features, save for the enormous petal shapes on the eleventh level. The provide significant shading to the levels below!

Insight Model

Right off the bat, we have a mean predicted EUI of 72.7 kBtu/sf/yr. This with all the BIM Model values for WWR, window shading (which I don’t have modeled, so it’s set to 0), wall construction, roof construction, and window glass.

I accepted a building orientation of 90 degrees (-3.70 EUI). While this orientation isn’t in the BIM model, I didn’t choose the BIM model’s specific orientation for any particular reason, so I’m happy to let Insight choose the best possible orientation on my behalf and update the BIM model accordingly.

Now if I go nuts with selecting the best remaining options, I can bring the mean predicted EUI all the way down to 1.39. The main factors driving this are plug load efficiency (0.6 W/sf, -9.59 EUI), HVAC (ASHRAE Package Terminal Heat Pump -36.69 EUI), and PV (20+ yr payback limit, 90% surface coverage, 20.4% efficiency for -41.90 EUI total).

Now if I’m willing to accept 2/3 height window shades for all of my windows, I can make the building produce more energy than it consumes! Woo!

These shades make the most difference for the western face (-6.45 EUI), southern face (-4.78 EUI) and eastern face (-4.31 EUI). The northern face shading by comparison helps much less (-1.42 EUI).

Adding this window shading has somehow broken the EUI meter, which no longer has any color to it. Weird, but I’m quite happy with a mean estimated EUI of -11.1.

If we override our BIM values, we can see how much theoretical room for improvement we have. Setting the WWR to 0% and giving our building a horrible, bunker-style atmosphere results in -2.01 EUI for the northern face, -11.96 EUI for the western face, -7.04 EUI for the southern face, and -6.46 EUI for the eastern face.

Changing wall construction to R38 wood gives -3.56 EUI, and changing roof construction to 10.25” SIP gives -2.69 EUI.

This results in a lowest possible EUI for my building of -21.9. Not bad, but I’m willing to produce less net energy if it means keeping my big windows.

I’m a little suspicious of how Insight is modeling my BIM settings for wall and roofing construction though, since my exterior walls have an entire foot of rigid insulation and my roofing has 6” of rigid insulation plus a foot of dirt on top. I went all out on insulating my building, so I think the BIM settings should be better than Insight’s alternatives.

If you got this far and read my whole journal entry, thanks for reading!