| Scenario | Floors | Doors/Floor | Main Entrances | Gates | Dual-Sided | Spares | Estimated Total |
|---|---|---|---|---|---|---|---|
| Small site office | 1 | 4 | 1 | 1 | No | 10% | 7 |
| Mid-rise block | 8 | 10 | 2 | 2 | Entry | 10% | 98 |
| High-rise + lobbies | 30 | 14 | 4 | 3 | Doors both | 12% | 981 |
| Phased compound | 3 | 8 | 2 | 2 | Mixed | 15% | 53 |
- Door points = (Floors × Doors/Floor) + Main Entrances + (Emergency Exits, if re-entry is controlled)
- Door keypads = ceil(Door points ÷ Average doors per keypad) × (1 for entry-only, 2 for dual-sided)
- Gate keypads = (Perimeter gates + Vehicle gates + Turnstiles) × (1 or 2)
- Lift keypads = (Lift cars × Keypads per lift car) + (Floors, if lobby keypads enabled)
- Temporary keypads = (Phases × Temp points/phase) × (1 or 2)
- Subtotal = Door keypads + Gate keypads + Lift keypads + Temporary keypads
- Spares = ceil(Subtotal × Spare %)
- Total = Subtotal + Spares
- Outdoor = round(Total × Outdoor %), Indoor = Total − Outdoor
- Count openings that need controlled entry: doors, gates, turnstiles, lift areas.
- Decide if you need dual-sided keypads for bidirectional control.
- Set “Average doors per keypad” above 1.0 only when keypads are shared.
- Add temporary phases if access points change as works progress.
- Choose a spare percentage suitable for site damage and late changes.
- Press calculate, review the breakdown, then export CSV or PDF.
Scope the controlled openings early
A keypad plan starts with a reliable opening schedule. Count doors that truly require credentialed entry, then separate public entrances from restricted circulation. On live sites, include welfare rooms, plant spaces, and stair re-entry points only when policy demands it. Include temporary cabins too. A clear scope reduces late additions, avoids duplicated devices, and supports accurate cabling and containment allowances.
Use sharing assumptions with care
Many projects group multiple openings under one keypad through interlocks, adjacent doors, or controlled vestibules. The “average doors per keypad” field expresses that efficiency. Use 1.0 for dedicated devices, and increase gradually only when hardware and wiring routes confirm sharing is practical. Validate with door schedules, security drawings, and maintainability checks before relying on higher ratios. Overstating sharing can undercount, while conservative inputs protect commissioning schedules.
Account for direction of travel
Bidirectional control often needs keypads on both sides of an opening. Set dual-sided for doors, gates, or temporary checkpoints when you must validate entry and exit independently. This improves accountability and reduces tailgating, but it also increases power, termination, and weatherproofing requirements. Consider reader height, accessibility, and queuing space to prevent crowding. Align dual-sided choices with fire strategy and pedestrian flow.
Plan spares and phased works
Construction environments are harsh, and access layouts change. A spare percentage covers damage, last-minute relocations, and device swaps during commissioning. Temporary phases model evolving compounds, hoardings, and shifting storage yards. Treat phase inputs as peak demand, then reuse devices where possible to control cost while maintaining continuity of access control.
Translate totals into procurement packages
The total is a planning quantity, not a purchase order by itself. Split indoor versus outdoor counts to select suitable housings, seals, and mounting kits. Confirm interface needs for lifts, turnstiles, and vehicle barriers. Finalize cable lengths, gland sizes, labels, and test sheets so installation teams can certify each opening. Pair the keypad number with controller capacity, network drops, and testing time so procurement matches the delivery program.
1) What does “average doors per keypad” represent?
It estimates how many controlled openings share one keypad through vestibules, interlocks, or grouped doors. Use 1.0 when each opening has its own device, and increase only when your hardware design and cable routes confirm sharing.
2) When should I select dual-sided control?
Choose dual-sided when users must be validated in both directions, such as secure corridors, bidirectional gates, or controlled re-entry points. It generally doubles devices at those points and may increase power, containment, and weather-rated requirements.
3) How are emergency exits treated in the calculation?
Emergency exits are excluded by default because many are egress-only. Enable the exit re-entry option only when policy requires a keypad for controlled return access, typically in stairs, refuge routes, or security-managed escape doors.
4) Why add a spare percentage?
Spares cover damage, commissioning swaps, and late design changes. Construction sites experience impact and exposure, and access layouts can shift. A modest spare allowance helps maintain progress without waiting for replacements or reordering.
5) How should I use the outdoor percentage?
Use it to split totals between indoor and weather-exposed devices for specification and budgeting. Outdoor-rated keypads may need higher sealing, heaters, sunshades, or stainless fixings, depending on the environment and mounting location.
6) Does the result include controllers and cabling?
No. The output is a keypad quantity for planning. You should still confirm controller capacity, door interface modules, power supplies, network drops, and testing time. Export the summary and align it with your access control design package.