Working share link to your Forma project, view access for the teaching team.
https://app.autodeskforma.com/board/up_qom1okmnwc/board_5fa9dfc5-56e9-4a3c-8e85-ff6c6a1d010d
Comparison matrix, one page.
Paste your comparison matrix here…
Design memo of 300 to 500 words: what you read in the site, the three strategies, what the analysis said, your recommendation, and the surprise.
Site reading: My site is a 22,965 sf surface parking lot in downtown San Mateo (37.56717, -122.32240), a few blocks from the Caltrain station. Before adding anything I ran the baseline on the empty lot. In June 100% of the ground gets 3+ hours of sun, and on Dec 21 it is still 87%, so the neighbors do not shade it much. Wind mostly comes from the west and the empty lot reads 30% sitting / 70% standing comfort with nothing uncomfortable. Two existing neighbor buildings touch the site limit, so I used each proposal's own buildings for GFA and carbon instead of the site totals.
Three strategies: All three hold about the same program (92k to 102k sf of multifamily). A - Courtyard Block: one 7 floor U-shaped bar, 50 ft deep, around an open courtyard. B - Podium + Tower: an 8 floor, 76 ft deep tower with a 2 floor podium along the street. C - Twin Bars: two parallel 8 floor bars, 50 ft deep, with a gap between them.
Analysis results: Sun (Dec 21, ground with 3+ hrs): A 24%, B 22%, C 22%. Daylight (facade with VSC 27+ / under 15): A 79% / 6%, B 82% / 12%, C 78% / 4%. Wind (area good for sitting): A 41%, B 39%, C 41%. No option had any uncomfortable area. Total carbon over 60 years: A 19.85M kgCO2e (194 per sf), B 18.16M (198 per sf), C 18.47M (200 per sf). About 86% of it is operational in every option. Microclimate (Jan 2pm) showed no thermal stress for any option, so it did not help me pick. Noise was a limitation. Forma had no traffic or rail data for this site, so all three showed 100% under 55 dB. That is not realistic next to the Caltrain tracks, so I did not use noise to compare.
Recommendation: I recommend A, the Courtyard Block. It fits about 11% more floor area than B or C, has the lowest carbon per sf, gets the most winter ground sun, and the courtyard ends up calm enough for sitting. B has a higher share of well-lit facade, but it also has twice as much badly lit facade as A, mostly where the deep tower presses against the neighbor. C has the fewest dark facades but the highest carbon per sf and less floor area. A's main downside is the dark inside corners of the U, which I would fix by notching or stepping down those corners.
Surprise: I expected the twin bars to win on daylight and the courtyard to be the dark, windy option. The numbers said the opposite. C had the lowest share of well-lit facade (78%), and A's courtyard had the most winter ground sun and calm wind. A was also the biggest building and still had the lowest carbon per sf, because the compact U has less exposed facade per floor than two separate bars.
Three massing images, one per proposal, from the same viewpoint
