IFC test fits on a Boulder industrial lot

The warehouse engine lays out every building that fits inside the setbacks of a vacant lot zoned Industrial-General in Boulder, Colorado, scores each layout and returns a ranked shortlist. The setbacks, the height limit and the floor area ratio come from the Boulder Revised Code. The chosen option becomes an IFC model through the builder.

119,000 SF, 250 ft by 476 ft, 11 dock doors, 28.6% coverage, 32 ft clear and 40 ft high under the height limit. The engine found it among 72 feasible layouts of 472 evaluated, in 5.9 ms. Generated 2026-10-23 with docs/launch/site/boulder/testfit.js (method).

What runs today: the engine in the core library, run by a committed script. The tool that hands this to an assistant, bim_testfit is in development. NativeBIM has no Boulder zoning tables, so no zoning screening ran on this lot.

The options

Site plans of three warehouse test-fit options on the same long, narrow lot with the street at the bottom. Each plan shows the lot outline, the area inside the setbacks, the building footprint with its office corner, dock and grade doors, the truck court and car parking; options one and three add a row of trailer stalls. — Drawn from the engine's layouts by `docs/launch/site/boulder/testfit.js`, 2026-10-23. 5675 ARAPAHOE AVE, parcel 146327000033; not a survey. Parcel boundary and zoning district: City of Boulder Open Data (CC0 1.0), accessed 2026-10-23. Development standards summarized from the Boulder Revised Code, Title 9. Layouts are hypothetical and not endorsed by or affiliated with the City of Boulder or Boulder County; verify current code before relying on it. Test-fit options are not a design.

Option	Building SF	Length × depth	Coverage	Dock doors	Car stalls	Trailer stalls	Truck court	Source
Rank 1	119,000	250 ft × 476 ft	28.6%	11	48	20	185 ft	Generated 2026-10-23 with `docs/launch/site/boulder/testfit.js` (method)
Rank 7	119,000	250 ft × 476 ft	28.6%	11	48	0	130 ft	Generated 2026-10-23 with `docs/launch/site/boulder/testfit.js` (method)
Rank 13	106,000	250 ft × 424 ft	25.5%	11	43	20	185 ft	Generated 2026-10-23 with `docs/launch/site/boulder/testfit.js` (method)
balanced objective	119,000	250 ft × 476 ft	28.6%	11	48	20	185 ft	Generated 2026-10-23 with `docs/launch/site/boulder/testfit.js` (method)
maxDocks objective	119,000	250 ft × 476 ft	28.6%	11	48	20	185 ft	Generated 2026-10-23 with `docs/launch/site/boulder/testfit.js` (method)

Objective of the ranked list: maxSF. Every option is rear-load at 32 ft clear with 50 by 52 ft bays.

What the engine did

472layouts evaluated over 12 orientations, 3 of them with street accessGenerated 2026-10-23 with docs/launch/site/boulder/testfit.js (method)

72layouts feasible inside the setbacks, the height limit, the floor area ratio and the program, 72 of them distinctGenerated 2026-10-23 with docs/launch/site/boulder/testfit.js (method)

5.9 msfor the whole search on a cold run; 3.5 ms median of 5 warm runs, on a 16-core desktopMeasured 2026-10-23 with docs/launch/site/boulder/testfit.js (method) (--time)

416,314 SFlot area from the outline (9.56 acres), 375,288 SF inside the setbacksComputed 2026-10-23 with docs/launch/site/boulder/testfit.js (method)

The brief, and where the run departs from it

36 ft clear height, 50 by 52 ft bays, 60 ft speed bays, rear-load docks, 200,000 to 300,000 SF, 3 to 5 percent office. Brief written 2026-10-23: docs/launch/site/boulder/brief.json. (method)

Clear height (ft): requested 36, run with 32. IG allows principal buildings 40 ft high (B.R.C. 9-7-1, Table 7-1). The engine adds 8 ft of structure and roof to the clear height, so 36 ft clear would be 44 ft; 32 ft clear is 40 ft. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).
Target size (SF): requested 200,000, 300,000, run with 100,000, 300,000. The base FAR of 0.5 (B.R.C. 9-8-2, Table 8-2) caps a one-story building at half the lot, under the requested floor. The window keeps the upper bound and lowers the floor so the engine reports the most the lot supports. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).
Sprinklers: requested ESFR, run with not modelled. The test-fit engine has no sprinkler input. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).
Office share: requested 3%, 5%, run with 3%, 4%, 5%. Enumerated so the engine chooses within the requested band. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).

The lot does not support the requested size. Probes with the requested window:

Asked for 200,000 to 300,000 SF: 432 layouts evaluated, 0 feasible. Run 2026-10-23 with docs/launch/site/boulder/testfit.js (method).
Asked for 150,000 to 300,000 SF: 432 layouts evaluated, 0 feasible. Run 2026-10-23 with docs/launch/site/boulder/testfit.js (method).

Assumptions

Setbacks: street 20 ft, rail 20 ft, side lot lines 12 ft. Front and rear from B.R.C. 9-7-1, Table 7-1, module f, with the Arapahoe Ave edge as the front and the rail edge as the rear. Interior side lot lines may be 0 or 12 ft; 12 ft is used. The engine applies a setback to buildings and paving alike. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).
Open space: 0.2. Table 8-1 gives 10 to 20 percent minimum open space for nonresidential uses in IG; the upper end is used. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).
Car parking: 0.4. Target of 0.4 stalls per 1,000 SF, an assumption with no source. Boulder parking standards are not encoded. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).
Lot outline: 4 served vertices dropped. Vertices that start lot-line jogs shorter than 5 ft are dropped so each lot line is one edge. Engine area 416314.2 SF. Recorded 2026-10-23 in docs/launch/site/boulder/brief.json (method).

Code inputs for zone IG

Boulder Revised Code 1981, Title 9, as published on Municode, read 2026-10-23. NativeBIM has no Boulder zoning tables, so these standards were read from the code and given to the engine as inputs; no screening of the result against the code ran. Outputs are drafts for review by the licensed professional of record.

Standard	Value	Cited	Source
Minimum front yard landscaped setback (ft)	20	B.R.C. 9-7-1, Table 7-1, module f	Read 2026-10-23 from the Boulder Revised Code
Minimum front yard setback for parking (ft)	20	B.R.C. 9-7-1, Table 7-1, module f	Read 2026-10-23 from the Boulder Revised Code
Minimum side yard from an interior lot line (ft)	0 or 12	B.R.C. 9-7-1, Table 7-1, module f, footnote (b)	Read 2026-10-23 from the Boulder Revised Code
Minimum rear yard setback (ft)	20	B.R.C. 9-7-1, Table 7-1, module f	Read 2026-10-23 from the Boulder Revised Code
Maximum principal building height (ft)	40	B.R.C. 9-7-1, Table 7-1: 40 ft in I-zones	Read 2026-10-23 from the Boulder Revised Code
Base floor area ratio	0.5	B.R.C. 9-8-2, Table 8-2, IG	Read 2026-10-23 from the Boulder Revised Code
Minimum open space, nonresidential (percent of lot)	10-20	B.R.C. 9-8-1, Table 8-1, IG	Read 2026-10-23 from the Boulder Revised Code

Reproduce it

node docs/launch/site/boulder/testfit.js
node docs/launch/site/boulder/testfit.js --time

The script reads the public record in docs/launch/site/boulder/parcel.json, derives the engine input, runs the engine and draws the figure; --time also times the search. Engine nativebim.testfit.warehouse 1.2.0, input hash fnv1a64:38abd4441c9c4e14.

Notices

NativeBIM is licensed software. It does not provide design, engineering or other professional services. Outputs are drafts for review by the licensed professional of record.

NativeBIM is not affiliated with, endorsed by or sponsored by the companies and organizations named here. Product names and marks belong to their owners.

NativeBIM is provided as is, without warranty of any kind. To the extent the law allows, FeatureBoard Labs Incorporated is not liable for indirect, incidental or consequential damages, lost profits or lost data, and its total liability is limited to the license fees paid in the 12 months before the claim. Read the license.

IFC test fits on a Boulder industrial lotIFC test fit: the largest warehouse the engine fits on this Boulder lot