The best time to install alarm, CCTV, door entry and data cabling in a renovation or extension is at first fix, while walls and ceilings are still open and at the same stage as the electrician's first fix. Cables are run and labelled before plastering, and the equipment is fitted at second fix once decorating is finished. Book the security installer when the floor plans are agreed, so device positions can be marked up before anyone starts cutting chases.
Key Takeaways
- Security cabling goes in at first fix, alongside the electrician and before plastering
- Equipment is fitted, programmed and tested at second fix, after decoration
- Decide panel, keypad, camera and door entry positions before first fix starts
- Missing first fix usually means chasing new plaster, surface trunking or a wireless system
- First fix and second fix can be priced and invoiced as separate stages
Renovations and extensions
Planning the security for your project?
SatFocus designs and installs alarms, CCTV, door entry, access control, data and AV for renovations, extensions and new builds across London, with cables run and labelled at first fix and equipment fitted at second fix. An accredited Ajax Systems partner with 200+ five-star reviews.
See how we work on security first fix and second fix projects.
What Do First Fix and Second Fix Mean for Security Systems?
Building work is usually split into stages. Security and low-voltage systems follow the same pattern as the electrics, which keeps cables hidden and gives a clean finish.
| Stage | What happens | When |
|---|---|---|
| Design | Device positions marked on the floor plans and a written quote prepared | Once the layout is agreed |
| First fix | Cables run, clipped and labelled to every device and panel position | Walls and ceilings open, before plastering |
| Plastering and decoration | Cable ends left coiled and protected | Other trades finish the rooms |
| Second fix | Detectors, cameras, keypads and door stations fitted, programmed and tested | After decoration, before move-in |
| Handover | Apps set up, users shown the system, completion certificate issued | When the system is fully working |
When Should You Book the Security Installer?
Book the security installer as soon as the floor plans are agreed, ideally a few weeks before the electrician's first fix. That gives time to mark up device positions, agree cable routes and order equipment. A short site visit once the strip-out is done lets the installer confirm routes through joists and stud walls before any boarding goes up.
Coordinating with the electrician matters. Low-voltage security and data cables are run on their own routes, kept apart from mains cables where they run alongside, and the electrician provides the power supplies the alarm panel, recorder and door entry need.
Which Security Systems Need Cables at First Fix?
| System | Cabling at first fix | Where cables are left |
|---|---|---|
| Intruder alarm (wired or hybrid) | Multicore alarm cable to each detector, keypad and siren | Panel, keypad, every detector and the external siren |
| CCTV | Network cable (Cat6) to each camera, powered over the same cable | Each camera position and the recorder location |
| Video door entry | Two-wire or network cable, depending on the system | Door station, each indoor monitor and the power supply |
| Access control | Cables to the lock, reader and exit button | Door frame, reader position and controller |
| Data and Wi-Fi | Cat6 to data points and ceiling Wi-Fi access points | Data cabinet, rooms and access point positions |
| Audio-visual | Speaker and network cables | Ceiling speakers, amplifier and TV positions |
What Should You Decide Before First Fix?
- Alarm panel location: somewhere secure and out of sight, with a power supply and a network connection.
- Keypad position: near the main entrance, inside the entry route.
- Camera positions: entrances, driveway, side returns and the rear garden, at a height that shows faces.
- Door entry: whether you want video, how many indoor screens, and where gate or door releases are needed.
- Recorder and data cabinet: one tidy location where CCTV, router and network equipment can live together.
- Future additions: spare cables to an outbuilding, gate or garden office are cheap to add now and difficult later.
What Happens If You Miss First Fix?
If the walls are already plastered, there are still good options, but each has a trade-off:
- Chasing the walls: cables can be buried in new chases, but this means making good and redecorating.
- Surface trunking: quicker and cheaper, but cables are visible.
- Wireless or hybrid alarms: professional wireless systems such as Ajax need no cables to each detector, so they are often the best choice when walls are finished. Our guide to wired vs wireless burglar alarms explains the differences.
CCTV cameras still need a cable for power and data, so it is worth running camera cables at first fix even if you choose a wireless alarm.
Can First Fix and Second Fix Be Priced Separately?
Yes. Many installers price and invoice first fix and second fix as separate stages, because months can pass between them on a large renovation. The first fix covers cabling, containment and labelling; the second fix covers equipment, programming, testing and handover. A clear cable schedule from first fix also protects you if another trade damages a cable before second fix.
Planning a Renovation or Extension in London?
Send your floor plans to info@satfocussecurity.co.uk and we will mark up device positions and give you a written quote for first and second fix. Builders, architects and designers can read more on our security first fix and second fix page, and self-builders can use our self-build security wiring checklist.
Frequently Asked Questions
When should alarm cables be installed in a renovation?
At first fix, when the walls and ceilings are open and at the same stage as the electrician's first fix, before any plastering.
Can my electrician run the alarm and CCTV cables?
Yes. The security installer can provide a cable schedule with positions and cable types, then fit, programme and test the equipment at second fix.
What if the walls are already plastered?
A professional wireless or hybrid alarm avoids most new cabling. CCTV cameras still need a cable each, which can be chased in or run in neat trunking.
How long after first fix is second fix done?
Second fix happens once decorating is finished, which can be weeks or months after first fix depending on the size of the project.
Do I need a site visit before first fix?
It is strongly recommended. A short visit confirms cable routes, panel location and camera positions before the walls are closed.
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