standard tier · 72 briefs · 1,368 runs · results db2e24e

CityFormGen

Generative and optimisation methods for middle housing, compared under matched compute

RESEARCH GENERATIVE-DESIGN BENCHMARK - NOT CONSTRUCTION DOCUMENTATION OR CODE CERTIFICATION.

easy · flats · 2 storeys

B0055: a courtyard on a 21.7 × 26.3 m lot

4 dwellings, 23 rooms. The pooled front across all methods holds 480 nondominated designs.

Requirements

Lot
21.7 × 26.3 m (571 m²)
Street side faces
15° (0 = north)
Setbacks front / rear / left / right
4.1 / 6.9 / 2.1 / 1.9 m
Storeys × height
2 × 2.8 m
Shared core
yes (access gallery + stair)
Open space, net of parking
34% of the lot
Parking spaces
0
Courtyard
39 m² requested
Tightness (programme / buildable volume)
0.535

Programme

DwellingTypeStoreyMin m²Rooms
U01BR046entry, living, kitchen, bathroom, bedroom primary
U12BR063entry, living, kitchen, bathroom, bedroom primary, bedroom secondary
U22BR163entry, living, kitchen, bathroom, bedroom primary, bedroom secondary
U32BR163entry, living, kitchen, bathroom, bedroom primary, bedroom secondary

Required contacts: entry–living, kitchen–living. Doors forbidden between: entry–bedroom_primary, entry–bedroom_secondary, kitchen–bathroom.

Results by method

MethodSolvedHVEvalssNotes
Heuristic100%0.1485146.6
Random search0%0.000150010.0
Simulated annealing67%0.05215007.7
NSGA-II33%0.01115006.3
CP-SAT0%0.00004.6solver timeout
Random sketch + repair33%0.05515005.9repair collapse
Heuristic-seeded NSGA-II100%0.17515008.5

Mean over 1 seeds (the heuristic is deterministic: one run).

Representative designs from the pooled front

Each is best on one objective, or the knee: the most balanced trade-off. None is best overall.

Closest attempts that failed

For methods that found nothing feasible: their least-infeasible design, with its violations marked on its page.

Pareto explorer

Loading designs…

Convergence on this brief

Archive hypervolume against evaluations, mean over seeds.

Heuristic
00.171500 ev
Random search
00.171500 ev
Simulated annealing
00.171500 ev
NSGA-II
00.171500 ev
CP-SAT
00.171500 ev
Random sketch + repair
00.171500 ev
Heuristic-seeded NSGA-II
00.171500 ev

What stopped designs here

Share of each method's evaluated designs that violated each constraint.
methodC04C05C06C07C08C09C10C11C14
Heuristic5%31%15%1%0%3%3%
Random search98%100%100%100%47%97%60%98%0%
Simulated annealing56%92%79%56%14%87%16%63%8%
NSGA-II46%70%75%29%6%90%13%59%1%
Random sketch + repair32%57%72%24%18%46%28%56%50%
Heuristic-seeded NSGA-II12%37%31%3%5%11%9%28%4%

Constraint definitions