The reason Openreach gets a bad reputation for cable routing is that they install to a tight time budget, engineers are scored on completed jobs, and the default if a cable can't be hidden in 10 minutes is to clip it round the door frame on the surface. That's how London ended up with an entire generation of houses where the phone wire runs in a straight line from the front door, across the hallway ceiling, down the living room wall and behind the sofa.
We do the opposite. Hidden routing is the default. Surface clipping is the fallback for buildings where there's genuinely no other route. Here's where each makes sense.
When hidden routing is possible
Hidden routing works wherever there's a void to put the cable in. The common voids in London housing:
Suspended timber floors. Most pre-1960s London houses, plus many '70s and '80s ones. Lift a couple of floorboards (or use existing electrician's access points), feed the cable through the joists, drop it through the wall to wherever you need it. Almost invisible when done.
Stud walls. Internal walls in most newer London builds, and partition walls in older ones, are usually plasterboard on a timber frame. Drill at top and bottom, fish the cable down inside the wall cavity, terminate at a wall plate. About 40 minutes per wall when conditions are good.
Skirting board voids. Most London skirting boards are nailed to a thin batten on the wall, with a gap of 10–15mm behind the skirting before the wall surface starts. Carefully lift the skirting, drop the cable into the gap, refit. Looks identical to before.
Roof voids and loft hatches. If you've got a loft, that's the highway for cable. Up through the ceiling on one floor, across the loft, back down through the ceiling at the destination. Especially useful for runs to upstairs rooms or for whole-house structured cabling.
Service voids in flats. Modern London flats often have dedicated service voids in walls and ceilings designed for exactly this kind of work. New-build flats are usually the easiest property type to install hidden cabling in.
David and Priya in Clapham — Edwardian terrace, three floors, dense plaster and original features they didn't want disturbed. The challenge was getting Cat6 from the ground-floor hallway (where the router was) up to ceiling-mounted access points on the first-floor landing and second-floor landing.
Turned out the old bell-wire route from the original GPO install ran up through a small channel inside the central stairwell wall — that's how they used to bring the phone wire from the master socket up to extension bells on each landing. The bell wire had been disconnected for 30 years but the channel was still there, hidden behind the plaster.
We used that as our route. Cat6 fed up the existing channel, drops out at each landing ceiling, terminated to flush wall plates. The only sign of the install is two small ceiling-mounted access points — and even those are barely visible in white painted ceilings. They got full WiFi coverage from basement kitchen to loft conversion with zero visible cabling anywhere. Half a day's work.
When hidden routing isn't possible
Some buildings just won't accept hidden cable. The main blockers:
Solid concrete floors. Many 1960s and 1970s London flats have solid concrete floor slabs. Nothing under them, nothing through them. Cable has to go around the perimeter or surface-run.
Solid masonry walls without chase. Listed buildings, Georgian houses with intact original plasterwork, anywhere where you can't or shouldn't chase into the wall to bury cable.
Concrete ceilings. '60s-'80s flats often have concrete ceilings. No void = no route, unless we install it in surface trunking.
Floor tile installations. Once tile is down (especially natural stone or porcelain), lifting it for cable routing is usually more disruptive than the cable run is worth. We'd rather leave the floor alone and go around.
New-build flats with shallow floor zones. Some modern new-builds have only 15-20mm of void between the structural slab and the floor finish, designed only for plumbing and electrics. No room for an additional Cat6 run.
When we recommend surface routing despite having the option
Sometimes hidden is technically possible but it's not the right choice:
- Listed or heritage interiors. If hiding the cable means cutting into original plasterwork, decorative coving, or anything that contributes to the building's listed status, we'd rather route it visibly in a thin trunking and preserve the fabric.
- Tenant in a rental flat. Cleaner to do a surface run that the tenant can have removed at check-out than to cut into walls and have a dispute with the landlord about repair.
- Customer wants the quickest possible install. Sometimes "fast and simple" is the right answer. A clean surface run in white mini-trunking matched to the skirting is invisible from a few feet and gets the line live the same morning.
- Temporary install. Office sublet, six-month lease, building due for refurbishment — no point committing to a hidden install you're going to remove.
Tom in Fulham wanted a single ethernet point at his front door for a PoE camera over the porch. Should have been simple. Got there and the front wall was solid Victorian brick with original coving — no void, no route.
Options were: cut into the original coving (no — heritage feature, listed-adjacent property), or surface-run in trunking down the wall (visible, against Tom's preference), or take the long way round. We took the long way round: through the floor of the entrance hall, into the void under the front porch, under the front path in armoured conduit, and back up through the porch wall to the camera mount. Took most of the morning. Tom got the install he wanted with no visible cable inside or outside. Coving intact.
Sometimes hidden routing means an extra hour or two of creative routing through unexpected voids. It's almost always worth it.
What surface routing looks like when done well
Surface routing has earned a bad reputation because most installs are awful — Openreach engineers stapling round-section cable across the front of door frames, oversized white trunking visible from across the room. Done properly, surface routing is barely noticeable.
Three things separate a good surface run from a bad one:
Use small-section trunking matched to the surface. 16mm × 8mm mini-trunking, painted to match the skirting before installation, is essentially invisible at distance.
Route along architectural lines, not across them. Cable follows the top of skirting boards, the edges of doorways, the line of picture rails. Never diagonally across a wall, never cutting through a feature.
Use proper corners and end caps. Internal corners, external corners, end caps, T-pieces — all available pre-formed. A surface run made up entirely of straight lengths with proper accessories looks like a designed installation. The same run with mitred straight lengths and no fittings looks rushed.
The time difference
Hidden routing typically takes 10–25% longer than surface clipping the same job — lifting and refitting floorboards, fishing cable through stud walls, chasing where possible, making good after. Cable lengths are roughly similar, just routed differently.
We don't treat hidden as an "upgrade" or "extra" — it's our default where the building allows. If we can't hide it, we'll tell you on the phone before we arrive and suggest the cleanest surface alternative.
The single thing nobody else does
When we hide cable, we leave a route note: a small slip of paper noting where the cable runs, taped inside the back of the wall plate where future engineers will find it. "Cat6 from this plate, vertical through stud cavity, into ceiling void, across ceiling to comms cupboard." Costs us 30 seconds at install. Saves an unknown future engineer hours of probing and head-scratching if there's ever a fault.
Most installers don't do this. It's why so many older installations are functionally unrepairable when they go wrong — the cable is there somewhere, but nobody knows where, and the wall isn't going to volunteer the information.
Common questions
When can't you hide the cable?
Solid concrete floors, solid masonry walls without chase access, listed building interiors, tile installations where lifting isn't viable, and some new-builds with shallow floor zones. In any of those cases we use neat surface trunking matched to the skirting.
Will hidden wiring damage decoration?
Some small plaster making-good is occasionally needed at cable entry/exit points. We use a filler that paints over cleanly. Final paint matching is the customer's. We don't disturb anything we don't have to.
Can hidden cables be repaired later?
Yes — and we label both ends plus leave a route note inside the wall plate so future engineers can trace it. The cables themselves are spec'd for 25+ years in walls. The labelling discipline matters more than the cable spec.
Want cabling that doesn't show?
Describe the property — age, walls, floors, where you want the cable to start and end. I'll tell you over the phone whether we can hide it and what the visible alternative would look like if we can't.