WiFi for large properties & multi-building estates.

There is a point at which a property becomes too big for a router. Not too big for "good" WiFi — too big for the very concept of a single radio sitting in a cupboard trying to push a signal through stone, lath, brick and forty metres of garden. When I walk into a twelve-bedroom Hampstead house and the owner tells me their broadband works in the kitchen but nowhere else, I already know what I am looking at: a domestic-grade router doing the job of a building-wide network. The fix is not a bigger router. The fix is a proper structured network with a central data cabinet, access points placed and powered properly, and the cabling to support it for the next decade. This article is about how I actually build that — and why WiFi large house London work almost always comes back to the cabling rather than the radios.

Why a single router cannot cover a large London property

A consumer router has, at best, two short omnidirectional antennas and a budget of a few hundred milliwatts. Ofcom limits the equipment, not the building. So when you put that router on the hall table of a thousand-square-metre house, it does what it was designed to do: cover a flat. The 5 GHz band — the band carrying any meaningful speed on WiFi 6 (802.11ax) — drops off sharply after the first solid wall. The 2.4 GHz band travels further but is so badly congested in central London that the throughput is often slower than a copper FTTC line from a decade ago. None of that is the router's fault. It is the physics of trying to broadcast a useful signal through Georgian masonry, lath-and-plaster, marble bathrooms and steel-framed orangery extensions.

Large properties also have a second problem that small ones do not: lots of devices. Multi-room audio, smart heating zones per floor, CCTV inside and out, doorbells at front and tradesmen's gate, alarm panels, smart blinds, fridges that announce themselves, pool plant, irrigation, EV chargers, staff laptops, guest phones, a child's gaming PC and the homeowner's video calls all live on the same network. A single radio cannot service that, and a mesh node tucked behind a sofa certainly cannot. What you need is more access points, each carrying a small share of devices, all wired back to one place. That is the entire game.

Start at the cabinet, not the router

The single most useful change I make on a large-property job is to take the brain of the network out of the cupboard under the stairs and put it into a proper data cabinet. Usually that lives in a plant room, a basement utility or — if there is no better option — a ventilated section of garage or boot room. Inside the cabinet I want the incoming line termination (the Openreach NTE5A or NTE5C master socket for copper, or the ONT for FTTP), the ISP router in passthrough or modem mode where possible, a router/firewall capable of handling VLANs, and a PoE switch big enough to feed every access point in the house with two or three spare ports for future growth.

The cabinet matters because everything else hangs off it. If the cabling all runs back to one place, faults are found in minutes instead of hours. If it runs to seven different cupboards because someone added bits over the years, every fault is a treasure hunt. I have spent entire mornings in lovely houses tracing where a previous installer dropped a cable into a void and never labelled it. The cabinet ends that.

What I put in a residential cabinet on a large job

• Patch panel terminating every Cat6 or Cat6a run to the patch panel, with each port labelled by room and by switch port.
• A managed PoE+ switch — PoE+ rather than basic PoE so the access points get enough power for the second radio.
• A small UPS so the network stays alive through the brownouts that hit central-London streets more often than people realise.
• Cooling — even passive ventilation makes a big difference to switch lifetime.
• A patch lead colour-code I write on the inside of the door so the next engineer (sometimes me, two years later) is not guessing.

Cat6 to every floor, every wing, every outbuilding

I prefer Cat6 for residential installs and Cat6a where I can pull it without ripping the place apart. Cat5e is acceptable for short runs but I will not put it into a wall on a job that is meant to last fifteen years. Each access point gets a single cable home to the cabinet, and that cable does two jobs at once — it carries the data and it carries the power, via PoE. If you have not seen a proper PoE access point install, this is the bit that surprises homeowners: there is no plug, no transformer, no visible wire. The unit sits flush on the ceiling, fed by a single Ethernet cable that disappears into the void. Everything I would normally say about good cabling lives on the structured Ethernet page.

The rule of thumb I work to on a large house is one access point per wing per floor, plus an extra one where the floor plan turns a corner around a chimney breast or a thick spine wall. On a typical four-storey detached you might end up with six to eight indoor APs. On a twelve-bedroom house with annexe, that number goes up. There is no "minimum" — every job is sized by the survey, not by what fits a price bracket.

Outdoor access points: gardens, pool houses and pavilions

The other thing big properties have that small ones do not is outside space. Real outside space. Lawns long enough to lose the dog in, pool houses fifty metres from the back door, garden studios, summer pavilions and tennis courts. None of that gets reliable coverage from an indoor AP through a triple-glazed door. The fix is outdoor-rated access points, mounted under eaves or on garden walls, fed by external-grade Cat6 with proper surge protection at the cabinet end.

Outdoor cabling needs more care than indoor. UV-resistant outer sheath, gel-filled cable on long runs across damp ground, properly grounded shielded terminations on metal-clad buildings, and conduit anywhere it crosses a flowerbed somebody might one day dig. I have replaced more than one cheap unshielded run that a fox or a gardener finished off. Do it once, properly, and it lasts.

Scenario one — twelve-bedroom Hampstead house with annexe and pool house

This is the archetype. Detached Edwardian villa on a long plot, late-twentieth-century rear extension with a glass-walled kitchen-diner, separate staff annexe over the garage, pool house at the bottom of the garden, garden studio used as a home office. Owners moved in, signed up for full-fibre, and were told by the ISP installer that the router would "cover the whole house". It covered, generously, three rooms.

What I did on that job:

1. Relocated the FTTP ONT and the router into a basement plant room, building a small ventilated cabinet next to the boiler.
2. Pulled Cat6 from the cabinet to a patch panel, then onward to seven indoor access points — two on the lower-ground, two on the ground, two on the first floor, one in the second-floor master suite.
3. Dropped a separate Cat6 run through the garden in armoured conduit out to the pool house, terminating in a small wall-mounted switch with its own AP.
4. Fed the garden studio with another armoured run and a single outdoor AP under the eaves, angled to also pick up the lawn.
5. Put the annexe on its own AP with a dedicated SSID and a guest-style VLAN so the family network and the staff network stayed separate.

The owner's complaint on the kitchen island disappeared the same afternoon I commissioned the network. The bigger win was that the property's CCTV, the pool heater controller and the garden irrigation all moved off shaky 4G dongles and on to proper wired backhaul. That is the kind of fix that justifies the work.

Scenario two — Knightsbridge listed mansion, no surface trunking allowed

Listed buildings change the rules. On a Grade II* Knightsbridge mansion last year, I was told — quite reasonably — that no surface trunking, no visible cable, no holes through cornicing and no fixings in marble. I have worked on enough listed buildings to know the answer is patience and using the routes the building already gives you.

That route is almost always vertical. Old service voids that once carried gas pipes or speaking tubes, the gaps behind a dumb waiter, redundant chimney flues, and the cavities behind panelled walls. None of those are visible from a finished room. With a fish tape, a torch and a couple of hours, you can usually pull a Cat6 from a basement plant room up to the third floor without putting a single mark on the property.

On that particular job:

• The cabinet went into a sub-basement strongroom that already had power and a phone line.
• I used the old servant-call wiring runs as messengers to pull modern Cat6a vertically through the house.
• Access points were chosen specifically because they had a white slim-profile fascia that matched ceiling roses on each floor — homeowners on heritage properties care about how things look, and rightly so.
• Where I could not get a wired AP into a particular reception room, I used a hidden AP behind a removable panel in an adjacent dressing room and tuned the channel/power so the coverage extended through the doorway.

The point I make to listed-building owners is that mesh-with-wireless-backhaul looks tempting on this kind of property — it promises "no cables" — but the reality is that any radio bouncing between mesh nodes through marble walls performs terribly. Wired backhaul, even if it has to take a slower scenic route through an old void, beats it every time. There is more on that trade-off in the mesh vs wired access points piece.

Scenario three — country-style property inside the M25

There are still pockets of London — bits of Barnet, Bromley, Richmond, parts of Stanmore and Chigwell — where the houses sit on three acres and feel like Hertfordshire. On that kind of property, the WiFi problem is not the house. It is the courtyard, the orchard, the paddock and the lawn between the main house and a converted barn used as a gym.

Standard mesh products genuinely cannot do this distance. The signal between mesh nodes on a long lawn collapses, and even when it holds, it halves the effective throughput on every hop because the radio is talking to the nodes and the clients on the same frequency. What works is outdoor APs with directional antennas pointing across the courtyard, and a dedicated wired link out to the barn so it has its own AP rather than relying on a long-range hop.

On a Stanmore three-acre job I ran:

1. An armoured Cat6a from the main house cabinet, under the lawn in conduit, into a small outbuilding cabinet at the barn.
2. An outdoor AP on the corner of the main house, covering the courtyard and the kitchen-garden side.
3. A second outdoor AP under the barn eaves pointing back across the lawn, so the gardener's tablet kept its connection while he was on the mower.
4. Two indoor APs inside the barn itself, on the wired backhaul.
5. The lot tied into a single management dashboard so faults could be triaged remotely — useful when the homeowner is in the Caribbean for two months and the gardener cannot get on the network.

The principle is the same on every big plot: the further away a building is, the more important it is to feed it with real cable rather than to hope a radio can reach it. Hope is not a network design.

Mesh with wired backhaul vs full wired access points

If you read consumer-tech reviews, mesh sounds like the answer to everything. In a flat or a small terrace it usually is. In a large London house it is not — unless the mesh nodes are wired together, in which case you have effectively built a wired access-point network and are using mesh kit to do it. Two genuine differences are worth knowing:

• Wireless-backhaul mesh uses the same radios to talk to clients and to talk between nodes. On a long house with thick walls, that means slow links and brittle handovers.
• Wired-backhaul mesh uses Ethernet between the nodes. Performance is fine. But you have already done the hard work — running the cable — so you might as well use proper wired access points and get full enterprise-grade roaming and VLAN support.

My standing advice: if the cabling exists, install proper wired APs. If the cabling does not exist but the building will not allow it, mesh with the best wireless backhaul you can get is a fair compromise. If the cabling does not exist but the building will allow it, install the cabling and stop trying to dodge the work. The building-materials piece explains why radio-only solutions struggle in London stock.

VLANs — guest, staff, IoT and family on the same wires

The other thing a big-house network does that a flat does not is segregate traffic. The family network does not want the cleaner's phone, the housekeeper's tablet, the smart fridge or the visiting plumber on the same broadcast domain as the children's school laptops. The right answer is VLANs — virtual networks running over the same physical cables, kept apart by the switch and the firewall.

Typical VLAN layout on a large-property job:

• Family — full access, including any home server or NAS.
• Staff — internet only, no access to the family side.
• Guest — internet only, rate-limited, captive-portal optional.
• IoT — smart-home devices isolated from everything else, talking outbound to their cloud but not inbound to laptops.
• CCTV — its own VLAN, hard-isolated, so a compromised camera cannot scan the rest of the network.

Each SSID maps to a VLAN. The user picks the right network from their phone, the switch handles the rest, and a fault in one segment does not take the whole house down.

FTTP, ONT placement and the cabinet

One detail I see ignored on big jobs is where the FTTP ONT actually lives. Openreach will fit it where it is convenient for the installer — which is often somewhere awkward for the network. On a large house, get it moved (or repositioned at install time) so it sits inside the cabinet next to the switch. If you cannot, run a short single fibre patch or a clean Ethernet between the ONT and the cabinet rather than relying on a long, scenic CAT5e ribbon. For copper FTTC homes the same principle applies to the master socket: keep the NTE5C, the router and the switch in one tidy place. The broadband engineer page has more on diagnosing the line side, and the WiFi survey page covers what a proper site visit involves.

The honest summary

A "WiFi problem" in a big London property is almost never a WiFi problem. It is a cabling problem, an access-point-placement problem and sometimes a building-fabric problem dressed up as a router complaint. The fix is not exotic. It is a cabinet, a switch, a measured number of properly placed APs, real cable in the walls, and a network design that knows the difference between a guest device and a family laptop. Done once, properly, it lasts a decade.

If you are sizing up that kind of job — Hampstead annexes, Knightsbridge listed work, country-style plots inside the M25 — I am happy to come and survey the property and tell you what is actually needed before any cable is pulled. No upsell, no scare stories. Just a plan that fits the building.

Ring 020 3633 1131. Honest advice, freely given.