Every door entry quote you send should land with your margin intact, and the thing that quietly eats it isn't the hardware spec, it's legacy wiring and the old rip-and-replace assumption that comes with it. So let's answer the question head on: what does cable labour actually cost on a UK residential job? It's rarely one fixed total, but installers run at roughly £300 to £500 per day, and on a retrofit the cable pulling alone can eat 60% to 70% of the whole project budget.¹ On a 30-apartment block, that's easily 10 to 14 days and £7,000 or more, before you've fitted a single panel.

We've spec'd door entry across hundreds of UK residential and commercial blocks, from 1960s estates to new-build developments, and we know how it feels to watch a healthy hardware quote get swallowed whole by the cabling line. So before you commit to ripping anything out, here's what actually drives that cost, and where the rip-and-replace assumption is quietly costing you money.

Because on most residential jobs it's the labour, not the hardware, that makes or breaks your margin. Which leads to the only question that really moves the needle on an upgrade: not "which system is best," but "how much of the existing cable can I avoid pulling in the first place?"

Older blocks and commercial buildings are full of legacy wiring, usually 4+N analogue, CW1308 telephone cable or RG59 coax, and most of it is plastered over, stuck behind fire-stopping risers or run through ducting you'll never reach without making a mess. Ripping it out is exactly the kind of slow, expensive work that kills your margin, and it's the rip-and-replace assumption, not the building itself, that does the real damage.

The great news is you often don't have to. Modern 2-Wire systems like Comelit Simplebus and Videx VX2300, or hybrid IP converters from Dahua and Hikvision, push digital video, audio, power and data down a single pair of non-polarised copper wires. So instead of two weeks of cable pulling, your team swaps the hardware in two or three days and you can cut the labour bill by anywhere from 50% to 80%, depending on the state of the building. Same building, far smaller invoice.

New builds flip it completely. The M&E contractor fits CAT5e or CAT6 as standard during first-fix,³ so the cost of running network cable is already baked into the shell. With structured cabling sitting there ready, full IP or SIP is the obvious call, powered straight over the network with standard PoE switches, future-proofed with app control and remote diagnostics, and happy to talk to your IP CCTV, Control4, Crestron and SIP setup.

Put the two approaches side by side on the same 30-apartment block and the gap is hard to ignore.

Going full IP with brand new CAT6 comes in around £25,100, while reusing the existing wiring with a 2-Wire hybrid system lands at £12,050. That's a saving of more than 50%, mostly because labour and remediation drop from nearly half the budget to about a fifth. Cheaper bid, quicker job, healthier cash flow.

So before you spec your next upgrade, the only question that really matters is simple: what's already in the walls, and how much of it can you keep?

You don't have to guess what's behind the plaster or default to rip-and-replace. Three steps take the gamble out of it.