How many cameras does a housing society need? A sizing method

Two vendors quoting twenty-four and sixty cameras for the same society are usually not disagreeing about security. They are answering different questions, neither of which was asked precisely.

A committee needs a number it can defend in a general body meeting, in front of members who are paying for it, and that survives the next committee taking over. That is a different requirement from simply covering the property.

Count decision points, not buildings

A decision point is a place where somebody chooses to enter, leave, or move between areas — and where knowing who made that choice would change what you can do about an incident. Cameras belong at decision points. Coverage between them is optional.

Walk the society and count them honestly. In most mid-size societies the total is far smaller than the number of walls, and it produces a figure you can justify line by line rather than defend as a lump.

The society positions that always justify a camera

• The main gate, both directions. Entry and exit are separate events, and a single camera angled at both usually reads neither at a usable size. This is also where vehicle records matter most.
• The pedestrian gate, if it exists separately. It is frequently the one nobody quoted for and the one most used.
• Each building entrance lobby. The pinch point every resident and visitor passes.
• Lift lobbies and staircase entries. One per building, at ground level, covering both routes upward.
• Basement or stilt parking, at the ramp and at aisle ends. The highest-incident area in most societies by a wide margin, and the most commonly under-covered.
• The guard cabin itself, covering the register and the barrier control. This protects the guard as much as it monitors them.
• Perimeter blind spots — the two or three places along the boundary where somebody could enter unobserved. Usually far fewer than the full perimeter.

Sum those and you have a defensible base. Every addition beyond it should answer a question a member has actually raised.

Where committees over-buy

• One camera per floor per wing. Enormously expensive, rarely reviewed, and answered better by covering the lift lobby and stairs at ground level.
• Full perimeter coverage where two or three positions cover the only realistic entry points.
• Resolution everywhere. Identification-grade resolution is needed at gates and lobbies. A parking aisle overview does not need it, and paying for it there shortens retention on every channel.
• Cameras in places that create resident objections — anything overlooking a flat door, window or private balcony. These generate complaints that stall the whole project, and they are avoidable at the design stage.

Phasing without losing the design

Most societies cannot fund everything in one year, and should not try. The trick is to phase in a way that does not strand the design when the next committee arrives.

Specify the full layout and the recorder capacity for the whole plan up front, then install in stages. That means buying a recorder with free channels and running cable in shared routes once, so that stage two is cameras only. Phasing without that planning means paying for the same cable route twice and replacing the recorder in year two.

The number you can defend in a meeting

Bring three things: a layout with each camera numbered, a one-line purpose for each number, and the retention the recorder will deliver at that camera count. A member who asks “why fifty-two?” gets fifty-two sentences rather than a shrug, and the proposal survives.

That document also protects the society later. When a future committee asks why a camera is where it is, the answer is written down instead of being lost with the people who approved it.