Storage
Surveillance Hard Drive — Why regular drives fail
CCTV writes video 24/7. Only surveillance-rated drives (WD Purple, Seagate SkyHawk) are built for it. Desktop drives die in months.
What it is
A 3.5" SATA hard disk optimised for continuous write with firmware that prioritises writes over reads.
Common sizes for CCTV: 1 TB, 2 TB, 4 TB, 6 TB.
How it works
- 1The DVR/NVR writes continuous or motion-triggered clips to the drive.
- 2Older footage is overwritten when the drive fills — 'loop recording'.
- 3H.265+ compression lets you fit 2× the days on the same drive.
Best fit for
1 TB — home, 2–4 cameras
~15 days of continuous footage. Fine for most families.
2 TB — shop, 4–8 cameras
~15 days at 8 cameras — enough to review after a weekly incident.
4 TB+ — office/factory or 30-day retention
Choose when insurance, audits, or law requires a month of playback.
Key specs to check
- Marked 'Surveillance', 'CCTV', 'Purple' or 'SkyHawk'.
- Workload rating ≥ 180 TB/year.
- 3-year manufacturer warranty.
- 5400 RPM is normal for surveillance — quieter, cooler.
When you can skip it
- You never intend to review footage — cheap DVRs can run without a drive but you lose the whole point.
- You already have cloud recording enabled and don't need local playback.
Common mistakes
- Using a laptop or desktop drive — it will fail from continuous write.
- Buying a drive bigger than the DVR supports (some 4-ch DVRs cap at 6 TB).
Brands we stock
Seagate
WD
Want help picking the right one?
Our 2-minute builder recommends the right kit for your environment — or chat with us on WhatsApp.