Calculator
2 decimals
Formula used
- Net usable area = Room area × Net-to-gross factor
- Circulation area = Net area × (Circulation allowance ÷ 100)
- Support area = Net area × (Support allowance ÷ 100)
- Effective station area = Net area − Circulation area − Support area
- Max stations = floor(Effective station area ÷ Station footprint)
- Seated capacity = Max stations × (Utilization ÷ 100) × Shifts
- Stations needed = ceil(Target users ÷ ((Utilization ÷ 100) × Shifts))
How to use this calculator
- Enter room area from drawings and select area units.
- Set net-to-gross to reflect walls and fixed elements.
- Choose allowances for circulation and support zones.
- Enter station footprint including chair clearance needs.
- Set utilization and shifts for realistic occupancy planning.
Example data table
| Room area | Net factor | Station footprint | Allowances | Max stations | Typical use |
|---|---|---|---|---|---|
| 90 m² | 0.85 | 3.0 m² | 20% + 10% | 21 | Small training lab with instructor zone. |
| 140 m² | 0.88 | 2.8 m² | 18% + 12% | 35 | Standard classroom lab with wide aisles. |
| 220 m² | 0.90 | 3.2 m² | 22% + 10% | 48 | Large lab, added equipment and storage. |
| 300 m² | 0.92 | 3.5 m² | 25% + 15% | 52 | High-capacity lab with robust circulation. |
Space inputs and net usable area
Computer lab capacity starts with gross room area from drawings or field verification. This tool converts ft², yd², or m² into a single metric baseline, then applies a net-to-gross factor to reflect walls, columns, and fixed obstructions. Typical early planning uses 0.80–0.92, while irregular rooms may need lower values. The resulting net usable area is the pool that supports stations, circulation, and support zones.
Circulation and support allowances
Aisle allowance reserves movement space for entry paths, wheelchair turning, and safe egress routes. Support allowance covers instructor space, printers, lockers, and IT racks. Together they reduce effective workstation area, so higher allowances can materially lower the maximum station count. Many construction teams begin with 18–25% circulation and 8–15% support, then adjust based on code, furniture program, and equipment density.
Workstation footprint and layout density
Station footprint represents desk, chair pullback, and access clearance. For compact training labs, 2.6–3.2 m² per station is common, while testing centers and accessibility-first layouts may exceed 3.5 m². Because max stations equals floor(Effective area ÷ Footprint), small footprint changes can swing capacity significantly. Use measured furniture specs when available, and include cable management, CPU stands, and monitor arm reach.
Utilization, shifts, and seated capacity
The seated occupancy capacity multiplies max stations by peak utilization and shift count. Utilization reflects real-world behavior: late arrivals, device downtime, and maintenance reduce simultaneous usage. For instruction-led sessions, 80–90% is typical; for open labs, 60–80% may be more realistic. Shifts model multiple daily sessions sharing the same stations, helping compare build cost versus operational throughput.
Interpreting results for construction decisions
Use “max stations” as a geometric ceiling and “recommended stations” as a planning number that preserves layout flexibility. If the recommended count is below program demand, revisit allowances, furniture selection, or room allocation before issuing layout drawings. Document assumptions in the notes field and export CSV or PDF for reviews. Final validation should include detailed furniture plans, electrical load checks, HVAC comfort, and sightline requirements.
FAQs
1) What does net-to-gross factor represent?
It estimates how much gross room area becomes usable floor area after walls, columns, and fixed elements are considered. Higher values mean fewer obstructions and more efficient rooms.
2) How should I choose circulation allowance?
Start with 18–25% for typical classroom-style layouts. Increase it for wider aisles, accessibility improvements, or high traffic, and reduce only if furniture plans confirm clearance.
3) Why is station footprint larger than just the desk?
A functional station includes chair pullback, legroom, access, and cable routing space. Using only desk size can overstate capacity and create unsafe or noncompliant layouts.
4) What does seated occupancy capacity mean?
It is the effective number of users served when utilization and shifts are applied. It helps compare operational throughput across different station counts and daily session schedules.
5) Can I use this for exam or testing labs?
Yes, but increase station footprint and circulation to reflect stricter spacing, proctor zones, and accessibility. Verify final spacing against program requirements and applicable regulations.
6) Which export should I share with stakeholders?
Use CSV for spreadsheets and scenario tracking, and PDF for review packages. Both include the saved inputs, allowances, and the computed capacities for quick approvals.