# CCTV storage and retention: how to plan it without overspending

> Storage is usually the second-largest line in a CCTV BOQ — and the most over-specified. Plan from three numbers: stream bitrate (Mbps per camera), retention days required by policy or regulator, and RAID overhead. Pair smart codecs (H.265, H.265+) with motion-based recording on low-activity zones to cut storage by 40–60% without losing forensic value.

**Author:** Arif Khan — Security Infrastructure & Building Technology Strategist  
**Published:** 2026-05-18  
**Reading time:** 6 min  
**Category:** [Security Infrastructure](https://arifkhanglobal.com/ask-arif/category/security-infrastructure)  
**Tags:** CCTV, Storage, NVR, Retention, H.265  
**Canonical:** https://arifkhanglobal.com/ask-arif/cctv-storage-and-retention-planning

## Short answer

Storage is usually the second-largest line in a CCTV BOQ — and the most over-specified. Plan from three numbers: stream bitrate (Mbps per camera), retention days required by policy or regulator, and RAID overhead. Pair smart codecs (H.265, H.265+) with motion-based recording on low-activity zones to cut storage by 40–60% without losing forensic value.

## Visual explanation

Worksheet: cameras × bitrate × hours × retention days ÷ codec efficiency, then RAID overhead and growth headroom — sized as NVR-attached, SAN or hybrid cloud cold storage.

## Real-world example

A 240-camera campus was quoted 1.2 PB for 30-day retention. Re-engineering with H.265+ smart codec, motion-based recording on parking and corridors, and a tiered hot/warm/cold storage plan brought the requirement to 410 TB — at the same forensic quality.

## Lessons

- Bitrate, not megapixels, drives storage. Tune VBR per zone.
- H.265+ and smart codecs cut storage 40–60% versus H.264.
- Tier storage: hot NVR, warm SAN, cold archive for incident retention.
- Plan RAID overhead and 20% growth headroom into the spec, not after.
- Match retention days to policy or regulator — over-retention is wasted money and a privacy risk.

## Related projects

- Corporate campus, Bengaluru
- Logistics yard, North India

## FAQ

### How many days of retention do we really need?

Most enterprises plan 30 days hot, 90 days warm; regulated industries (banking, critical infrastructure) extend to 180–365 days on tiered storage.

### NVR, SAN or cloud?

Hot recording stays on NVRs near cameras. Warm/cold tiers go to SAN or object storage. Cloud is right for cold archive and disaster-recovery copies, not primary recording.

---

Source: https://arifkhanglobal.com/ask-arif/cctv-storage-and-retention-planning
Site: https://arifkhanglobal.com · Altima Global