Working links to all three models in Forma Data Management and your Forma Board
Please paste your working links to all three models and your Board here…
PDF sheet set at E1 size, 30 by 42 inches
Please paste your PDF sheet set here…
Load summary table: floor total and by zone
Please paste your load summary table here…
Alternatives comparison: your representative unit and your alternative unit, compared by numbers, with your conclusion
Please paste your two alternatives comparison here, what differs between them, and which you choose and why…
Design memo of 300 to 500 words: your strategy and why, what the loads told you about your envelope, where your structure got in the way, and what you left unresolved
Design Strategy:
The project is located in Oakland Chinatown, California (37.798° N, 122.269° W), which falls under CEC Climate Zone 3 (ASHRAE 3C, marine). The climate is mild and strongly heating-dominated, with minimal cooling demand. The psychrometric analysis shows that only 7.8% of annual hours (682) are comfortable without assistance. Internal heat gain (50.2% of hours) and passive solar direct gain with high thermal mass (19.8%) are the most effective passive strategies, with window shading (9.6%), thermal mass (2.8%), and natural ventilation (2.5%) contributing as well. Together, these strategies make 8,758 of 8,760 hours comfortable. Mechanical heating, with humidification if needed, is still required for about 30.1% of hours (2,639), while cooling is needed for only 12 hours per year.
Both buildings are rotated approximately 25° clockwise from true north, so their principal facades face NNE, ESE, SSW, and WNW. A moderate window-to-wall ratio limits heat loss and unwanted solar gain. The largest glazing faces SSW, shaded by overhangs, with smaller openings on the ESE and WNW facades, where low-angle sun is harder to control. Because the SSW facade sits 25° west of due south, it still receives meaningful afternoon sun, so shading depth should be checked for that. A heavyweight concrete floor topping slab is placed where it receives direct sun from the ESE in the morning and the SSW/WNW in the afternoon, storing heat and reducing peak loads.
Ventilation is mixed-mode. Operable windows provide natural cross-ventilation during mild periods, mainly in through-units and corner units. During wildfire smoke days and periods of high urban noise, windows stay closed and a dedicated balanced mechanical system with heat recovery supplies filtered outdoor air. Heating and cooling come from decentralized, in-unit ducted heat pumps with rooftop air-source condensers and sub-metering per tenant. Ducts run in soffits along the corridor side to ceiling supply diffusers. The alternative layout places a fan coil in the corridor drop ceiling with a branch main.
Standard units are single thermal zones with one smart thermostat. Corner units are split into two zones by orientation to prevent imbalance from shifting solar exposure. In Building 1, A208 is the single-zone unit, A202 the multi-zone unit, and A206 the alternative. In Building 2, B212 is the single-zone unit, B205 the multi-zone unit, and B211 the alternative. Occupancy was set at [bedrooms + 1] per unit rather than the default space-type density.