The temptation to add a second router
When a corner of the house shows a weak signal, the instinctive solution is to plug another router in the problem area and point it at the existing network. The idea feels straightforward – two boxes, two Wi‑Fi zones, better coverage. In practice, however, stacking two routers in their default router mode can turn a simple home network into a tangled mess.
What happens when you stack routers?
A typical home router does two things: it creates a local network and it performs Network Address Translation (NAT) so all your devices share a single public IP address. When you connect a second router behind the first without changing its mode, the newcomer also starts its own NAT process. This configuration, known as double NAT, means you now have two separate private networks stacked one on top of the other.
For everyday web browsing or video streaming the slowdown is often invisible, but the hidden complications surface with services that need a direct line to a specific device – online gaming, remote desktop, certain smart‑home hubs, and any application that relies on port forwarding or UPnP. Devices on different sub‑nets may also struggle to see each other, making simple tasks like printing from a laptop on the first router to a printer on the second a headache.
A cleaner way to spread Wi‑Fi: mesh systems
Instead of creating a second routed network, consider a mesh Wi‑Fi system. Mesh kits consist of a primary node that connects to your modem or gateway and one or more satellite nodes that communicate with the primary unit to form a single, seamless SSID. Because all nodes share the same routing layer, there’s no double NAT and devices move between nodes without dropping connections.
Many UK retailers now bundle mesh kits from brands such as TP‑Link Deco, Google Nest Wi‑Fi, and Netgear Orbi. They’re priced competitively and often qualify for contract‑free purchase, making them a practical upgrade for households that already have a decent broadband deal.
Repurposing an old router as an access point
If you already own a spare router, you don’t need to buy a dedicated extender. Most modern routers include an access‑point (AP) mode. In this mode the device disables its routing functions – firewall, NAT, DHCP – and simply acts as a Wi‑Fi bridge, handing all traffic back to the primary router.
To set this up:
- Connect the old router to the main router via Ethernet (ideally using a wall‑jack if you have one in the weak‑signal room).
- Log into the secondary router’s admin page and switch it to AP mode (the exact wording varies by manufacturer).
- Disable the Wi‑Fi on the primary router for the same channel to avoid interference, or keep both active on different channels for added capacity.
In AP mode you retain the secondary router’s Wi‑Fi capabilities while avoiding the double NAT pitfall. Note that some features – VPN passthrough, QoS, parental controls – are disabled, which is usually acceptable if the device’s main job is to extend coverage.
When you just need more Ethernet ports
Sometimes the problem isn’t Wi‑Fi at all but a shortage of wired sockets. A simple Ethernet switch plugs into any free LAN port on your main router and instantly adds 5‑8 additional RJ‑45 ports. Switches are cheap, plug‑and‑play, and they never interfere with routing because they operate at Layer 2 only.
Dealing with ISP‑provided gateways
Most UK broadband providers – BT, Virgin Media, Sky, TalkTalk – supply a combined modem/router unit, often called a gateway. By default this device performs NAT, so plugging a personal router into it without adjustments creates double NAT again.
Two common work‑arounds exist:
- Bridge mode: If the ISP gateway supports it, enable bridge mode so the gateway becomes a pure modem, handing all routing duties to your own router or mesh system. The exact steps differ between providers, so consult the ISP’s support pages before toggling this setting.
- AP mode on the personal router: Keep the ISP gateway as the primary router and set your own device to AP mode. This preserves the ISP’s routing functions while still letting you benefit from better Wi‑Fi hardware.
Be aware that enabling bridge mode may disable features like IPTV or VoIP that some providers bundle with the gateway, so weigh the trade‑offs.
When two routers actually make sense
There are legitimate niche scenarios where running two routers in parallel is intentional:
- Home labs: Tech enthusiasts often isolate experimental servers, Docker containers, or IoT devices on a separate network to protect the main household traffic.
- Testing new firmware: Before flashing a new ROM or custom firmware on your primary router, you can spin up a secondary unit to trial the changes without risking the whole home network.
- Separate guest networks: Some users prefer a completely isolated guest network that sits on a different subnet for privacy reasons; a second router can provide that segregation.
In these cases the double NAT is a feature, not a bug, because the goal is to keep traffic streams distinct.
Bottom line for UK households
For the majority of renters and homeowners who simply want stronger Wi‑Fi or a few extra Ethernet sockets, adding a second router in its default mode is overkill and can cause more trouble than it solves. Opt for a mesh system, switch an old router to AP mode, or install a modest Ethernet switch. If you’re dealing with an ISP‑supplied gateway, decide whether you want it to stay in charge (use AP mode on your own device) or hand over control (enable bridge mode on the gateway).
Only when you have a clear purpose – a lab, a test environment, or a deliberately split network – should you keep two active routers. Otherwise, the modern alternatives are cheaper, easier to manage, and keep your home network running smoothly.
This guide adapts the technical insights originally published by Engadget on 6 September 2026, re‑framed for UK readers looking to optimise their home broadband without unnecessary hardware.