Calculator Inputs
Example Data Table
| Scenario | Area (sq ft) | Width (in) | Speed (ft/min) | Passes | Efficiency (%) | Estimated Total (hh:mm) |
|---|---|---|---|---|---|---|
| Light dust, open room | 1,200 | 14 | 120 | 1 | 80 | 0:55 |
| Moderate dust, obstacles | 2,500 | 14 | 100 | 2 | 70 | 2:10 |
| Containment, slow detailing | 3,600 | 12 | 80 | 2 | 60 | 3:45 |
| Heavy dust, triple pass | 5,000 | 14 | 90 | 3 | 55 | 7:05 |
Formula Used
1) Convert width to feet: Width(ft) = Width(in) ÷ 12
2) Effective sweep width: Weff = Width(ft) × (1 − Overlap%)
3) Raw productivity: Praw = Weff × Speed(ft/min) × 60 (sq ft/hr)
4) Apply passes and efficiency: Peff = (Praw ÷ Passes) × Efficiency%
5) Base run time: Trun = Area ÷ Peff (hours)
6) Idle factor: Trun,adj = Trun × (1 + Idle%)
7) Filter changes: N = floor((RunMinutes − ε) ÷ Interval), delay = N × ChangeMinutes
8) Total time: Ttotal = Setup + Trun,adj + FilterDelay + MoveDelay
How to Use This Calculator
- Measure the area inside the cleanup boundary, then choose units.
- Enter vacuum head width and a realistic controlled walking speed.
- Set overlap and number of passes based on dust load and standards.
- Use the efficiency factor to reflect obstacles, edges, and detailing.
- Add setup time, idle factor, and expected filter change behavior.
- If cords and hoses must be moved often, include move assumptions.
- Press Calculate Time to view totals and export files.
Work Area Definition and Dust Pathways
Define the vacuuming boundary from plans, containment, and airflow layout. Record accessible square footage, then note tight corridors, doorway thresholds, and corners that reduce pace. Add overlap when debris bands are uneven or when cross‑passes are required. For rough concrete or grout lines, lower speed assumptions and expect more edging time. On site.
Productivity Drivers from Width, Speed, and Passes
Coverage begins with effective sweep width and a controlled walking speed. Wider heads increase output only when turning space exists. Multiple passes divide productivity because each pass re-covers the same area. Use one pass for light dust, two for visible film, and three when clearance criteria are strict. Efficiency represents detailing and obstacle avoidance.
Delay Allowances for Filters, Repositioning, and Setup
Schedule loss often comes from controls rather than walking. Setup minutes cover PPE checks, cord routing, and staging. Filter changes create discrete downtime; choose an interval based on dust loading, bag capacity, and disposal rules. Include brief pauses for bag sealing, wipe-down, and entry/exit through decon points. Repositioning grows with segmentation, so use moves per 1000 square feet to scale travel and reset delays.
Interpreting Results for Crews and Shifts
The output separates run time, delays, and total duration in hours and hh:mm. Compare totals with shift windows and sequencing with other trades. If time exceeds one shift, divide the footprint into zones and calculate each zone with realistic access and setup. For critical areas, add buffer time for inspection, touch-up vacuuming, and documentation. Crew size and rate estimate cost, but productivity seldom scales linearly.
Field Validation and Continuous Improvement
After day one, capture actual start, stop, and downtime causes. Update speed, overlap, efficiency, and delay settings to match site behavior. Track filter life by time and observed dust levels. Keep a log of square footage completed per hour to refine future assumptions. Document constraints such as clutter, wet floors, or electrical limits. A calibrated model improves bids, schedules, and safer dust control.
FAQs
What overlap percentage should I use for HEPA vacuuming?
Use 10–20% for open floors with clear sight lines. Increase to 25–35% where debris lines are visible, edges are critical, or you must track around obstacles. Higher overlap improves capture but increases time.
How do I choose an efficiency factor?
Start at 75–85% for open areas. Use 60–70% for rooms with furniture, columns, or frequent edging. Drop to 50–60% for tight containment, heavy detailing, or multiple transitions and thresholds.
When should I plan filter changes?
Set an interval based on dust load and manufacturer guidance. If suction drops or bags fill quickly, shorten the interval. Include the full safe change process, including sealing, wiping, and disposal steps.
Does adding more workers reduce the total time?
Not always. Two workers can help by leapfrogging cords, moving obstacles, and handling bags, but congestion can reduce speed. Use the tool to estimate total hours, then validate productivity in the field.
Why is my calculated time much higher than expected?
Common causes are low width, slow speed, high passes, or a conservative efficiency factor. Also check overlap, planned filter downtime, and repositioning inputs. Adjust inputs using observed site data after the first zone.
Can I use the calculator for walls or ceilings?
Yes, if you convert the surface to an equivalent square footage and choose realistic width and speed values for vertical work. Increase passes and reduce efficiency because overhead movement, ladders, and edging slow production.