Zone depths per use type — sources, values, rationale
Companion: bim-building-width-method for the formula and the mirror cross-section.
This article catalogues the per-side zone depths feeding the Tile system and the floor plate methodology; the inventory of named Key Plans is in the Key Plans index. Sub-type specialisations are documented under Professional Office and its Medical, Business, and Private Office sub-articles.
Summary table — canonical values
The Z1/Z2/Z3 values below are the per-side depths (Z1 and Z2 are mirrored, Z3 is centreline single). All values trace to the cited source.
| Use Type | Z1 Habitat | Z2 Magazine | Z3 Corridor | Building Width | Source |
|---|---|---|---|---|---|
| Private Office | 5.9944 m / 19'8" | 1.3716 m / 4'6" | — | 14.73 m / 48'4" | PO-1/PO-2/PO-3 sketches |
| Academic | 4.7 m / 15'5" | 3.0 m / 9'10" | — | 15.40 m / 50'6" | Summary V2, 2025-05-13 |
| Professional Office (V12 baseline) | 6.0 m / 19'8" | 3.0 m / 9'10" | 3.0 m / 9'10" | 21.00 m / 68'11" | V12, 2025-01-07 (Z2/Z3 marked TBD) |
| Laboratory | 6.7818 m / 22'3" | 4.8006 m / 15'9" | 3.048 m / 10'0" | 26.21 m / 86'0" | Summary V2; IBC high-hazard egress |
| Medical | 7.2819 m / 23'10" | 4.877 m / 16'0" | 2.892 m / 9'5" | 27.20 m / 89'3" | M3/M1/M2 sketches (286 5/8" + 192" + 113 7/8") |
| Business | 5.51 m / 18'1" | 9.26 m / 30'5" | 2.75 m / 9'0" | 29.30 m / 96'2" | Notes V3 Option A/A (widest enumerated) |
| Civic | 6.0 m / 19'8" | 7.23 m / 23'9" | 3.6 m / 11'10" | 30.06 m / 98'8" | Synthesised values; no completed sketch |
Formula: Width = 2 × (Z1 + Z2) + Z3. See bim-building-width-method for the derivation.
Per use type
Private Office (PO-1 / PO-2 / PO-3)
| Zone | Value | Sketch evidence |
|---|---|---|
| Z1 Habitat | 5.9944 m / 19'8" | "19'-8"" on each of PO-1, PO-2, PO-3 |
| Z2 Magazine | 1.3716 m / 4'6" | "4'-6"" on each sketch (shallow storage zone, below the dashed centreline) |
| Z3 Corridor | — (none) | Each office opens to the shared building corridor (outside the leasehold) |
| Key plan SF | PO-1 = 325, PO-2 = 465, PO-3 = 685 | Sketch labels |
| Key plan m² | 30.19, 43.20, 63.64 | Calculated from SF |
| Building width | 14.73 m / 48'4" | 2 × (5.9944 + 1.3716) |
Private Office is the narrowest of the use types. The 5.9944 m Habitat is marginally under the 6.0 m European Lighting Standard threshold — flagged for review at Key Plan sign-off.
Combinations: PO-1 + PO-1 = 60.4 m² (650 SF); PO-1 + PO-2 = 73.4 m² (790 SF); PO-1 + PO-3 = 93.8 m² (1,010 SF); PO-2 + PO-3 = 106.8 m² (1,150 SF). These fill the gap between Private Office Large and Professional Office Small.
Academic (A1 / A2 / A3)
| Zone | Value | Source |
|---|---|---|
| Z1 Habitat | 4.7 m / 15'5" | Summary V2 |
| Z2 Magazine | 3.0 m / 9'10" | Summary V2 (the source shows "3'7"" in feet, which is a transposition; 3.0 m = 9'10" is correct) |
| Z3 Corridor | — (none) | Suites open to building corridor |
| Key plan m² | Small 87.7 / Medium 240.3 / Large 376.3 | Key Plans Samples V2 |
| Key plan SF | Small 944 / Medium 2,586 / Large 4,050 | |
| Building width | 15.40 m / 50'6" | 2 × (4.7 + 3.0) |
Academic compresses Habitat below 6 m because seating faces forward (toward a podium/board) rather than toward the façade. The European Lighting Standard applies to workstations; auditorium-style seating is not workstation use.
Inconsistency: building-width-calculator.dtcg.json records Academic Small as 105 m² / 1,131 SF, while professional-office-subtypes.dtcg.json records it as 87.7 m² / 944 SF. Pending operator decision on which is canonical.
Professional Office (baseline)
| Zone | Value | Source |
|---|---|---|
| Z1 Habitat | 6.0 m / 19'8" | V12 (January 2025) |
| Z2 Magazine | 3.0 m / 9'10" | V12 — marked "TBD"; placeholder |
| Z3 Corridor | 3.0 m / 9'10" | V12 — marked "TBD"; placeholder |
| Key plan m² | Small 130.06 (only) | DTCG token; Medium/Large pending |
| Key plan SF | Small 1,400 (only) | DTCG token |
| Building width | 21.00 m / 68'11" | V12 stated total |
Professional Office is the baseline use type — the type from which the other Professional Centre sub-types (Medical, Business, Laboratory, Academic, Civic) are derived by varying Z1, Z2, and Z3.
V12 explicitly marks Z2 and Z3 as "TBD" with 3 m placeholders. When the Professional Office Key Plan is completed, the operator will lock Z2 and Z3 to match the furnished layout.
Laboratory (L1 / L2 / L3)
| Zone | Value | Source |
|---|---|---|
| Z1 Habitat | 6.7818 m / 22'3" | Summary V2 |
| Z2 Magazine | 4.8006 m / 15'9" | Summary V2 |
| Z3 Corridor | 3.048 m / 10'0" | Summary V2 (IBC high-hazard occupancy minimum) |
| Key plan m² | Small 195.0 / Medium 316.0 / Large 400.7 | Samples V2 |
| Key plan SF | Small 2,099 / Medium 3,401 / Large 4,313 | Samples V2 |
| Building width | 26.21 m / 86'0" | 2 × (6.7818 + 4.8006) + 3.048 |
Laboratory's wider Z1 accommodates bench depth (Treston TP-915 ≈ 900 mm) and fume-hood clearance (≈ 940 mm + 1,500 mm egress in front of the hood). The 10'0" corridor is the IBC high-hazard occupancy egress minimum.
Specialisations: Medical Laboratory, Research Laboratory.
Medical (M1 / M2 / M3)
| Zone | Value | Sketch evidence |
|---|---|---|
| Z1 Habitat | 7.2819 m / 23'10" | "286 5/8"" on M1/M2/M3 (= 7.282 m) |
| Z2 Magazine | 4.877 m / 16'0" | "192"" on M1/M2/M3 (= 4.877 m) |
| Z3 Corridor | 2.892 m / 9'5" | "113 7/8"" on M1/M2/M3 (= 2.892 m) |
| M3 (Small, 2 dental chairs) | 2,401.5 SF / 223 m² | Sketch label |
| M1 (Medium, 4 dental chairs) | 3,567.7 SF / 331 m² | Sketch label |
| M2 (Large, 6 dental chairs) | 5,231.4 SF / 486 m² | Sketch label |
| Building width | 27.20 m / 89'3" | 2 × (7.2819 + 4.877) + 2.892 |
Medical has the widest Habitat across the use types. The depth accommodates exam-table depth (Midmark 626 ≈ 790 mm) plus patient seating, clinician circulation, and a reception window facing the façade. The 2.892 m corridor is the ADA/CSA-B651 stretcher-and-wheelchair clearance.
Operator notes on the M3 sketch flag: "Add second door for emergencies", "Line of sight — safety — reception needs to see the door", and "Move seats down out of Zone #1".
Specialisations: Dentist, General Practitioner.
Business (B1 / B2 / B3)
The Business use type has 21 enumerated width options per Notes V3. The token store records the widest symmetric option as the default:
| Zone | Value | Source |
|---|---|---|
| Z1 Habitat | 5.51 m / 18'1" | Notes V3 Option A |
| Z2 Magazine | 9.26 m / 30'5" | Notes V3 Option A (widest enumerated) |
| Z3 Corridor | 2.75 m / 9'0" | Notes V3 (fixed across all 21 options) |
| Key plan SF | Small 3,350 / Medium 4,302 / Large 7,524 | Sketches 2-4 |
| Building width | 32.29 m / 105'11" | 2 × (5.51 + 9.26) + 2.75 (Option A/A) |
Important caveat: Notes V3 enumerates 21 combinations (Option A/A through D/D), where the two letters denote the left-side and right-side Z1/Z2 choices. The narrowest Business option is 25.29 m (D/D) and the widest is 32.29 m (A/A). The asymmetric options are generally disfavoured for tile composition because demising walls must absorb the asymmetry.
From operator commentary in Notes V3 on Option D: "The overall area of the Fixed Floor Plates [is] Professional Centres at approximately 19,000 SF to 23,000 SF and Suburban Office at approximately 17,000 SF to 21,000 SF."
Civic (C1 / C2 / C3)
| Zone | Value | Source |
|---|---|---|
| Z1 Habitat | 6.0 m / 19'8" | Synthesised (no completed sketch) |
| Z2 Magazine | 7.23 m / 23'9" | Synthesised (token store value) |
| Z3 Corridor | 3.6 m / 11'10" | Synthesised — public assembly egress |
| Key plan m² | Small 270 / Medium 577 / Large 822 | Token store (samples-derived) |
| Key plan SF | Small 2,912 / Medium 6,215 / Large 8,850 | Token store |
| Building width | 30.06 m / 98'8" | 2 × (6.0 + 7.23) + 3.6 |
Civic does not yet have a completed sketch. Z1/Z2/Z3 values in the token store are synthesised from the design intent (public records storage; widest corridor for ceremonial circulation and public assembly egress). Specialisations: Courtroom, Municipal Office, Cultural Space, Civic Assembly.
The 0.7 m perpendicular-desk addition
Applies to any Z1 Habitat that arranges desks perpendicular to the façade. Token: bim.circulation-addition.perpendicular-desk = 0.7 m. Effective Z1 = 6.0 + 0.7 = 6.7 m when perpendicular desks are required to seat three desks in series.
Floor-plate target ranges
| Class | Range |
|---|---|
| Professional Centres | 19,000 – 23,000 SF |
| Suburban Office | 17,000 – 21,000 SF |
The current token store hard-codes 20,000 SF as floorPlate.netLeasableSF. Convert to a range with PC and SU variants.
Future research
- Confirm Academic Small key plan area: 87.7 m² (944 SF) per Samples V2 vs. 105 m² (1,131 SF) per DTCG token store
- Complete Civic sketch to anchor Z1/Z2/Z3 values to a real furniture arrangement
- Confirm operator preference for Business: Option A/A (widest, 32.29 m) versus a balanced option such as C/C (~27 m)
- Capture manufacturer SKU dimensions in a
furniture.dtcg.jsonfile - Complete Professional Office Z2/Z3 (currently V12 placeholders at 3 m / 3 m TBD)
- Document the 0.7 m perpendicular-desk supplement as an effective-Habitat modifier
- Verify whether the 6.0 m Habitat tracks a specific clause in EN 12464-1
Source-document inconsistencies (open)
| # | Issue | Action |
|---|---|---|
| 1 | Academic Small area: 105 m² (DTCG) vs 87.7 m² (subtypes DTCG / Samples V2) | Operator decision needed |
| 2 | Medical Z1 token = 7.2 m, sketch = 286 5/8" = 7.28 m | Token file pending update to 7.2819 m |
| 3 | Professional Office Z2/Z3 placeholders (V12: 3 m / 3 m TBD) | Values to confirm from Key Plan |
| 4 | Floor-plate hard-coded 20,000 SF; Notes V3 directs ranges | Convert to range token |
| 5 | 21 m PDF total vs prior 21.6 m token arithmetic | Reconciled 2026-05-17 by restoring V12 values |