Mesh or a Wi-Fi extender

One weak room and a tight budget point to an extender. Several weak rooms, or a weak room where the speed also collapses, point to a mesh system — and in both cases a cable, where one is possible, beats either.

What an extender really does

An extender receives the router's signal and retransmits it. Unless it has a second radio dedicated to the link back, it does both jobs on the same channel, which halves the throughput available to anything connected through it. You get more bars and less speed, and that trade is fine if the goal is a reliable signal for a phone or a smart speaker in one corner of the house.

It also normally creates its own network name, so devices do not hand over cleanly. A laptop carried across the house often clings to the weak original signal until it drops completely, which is the reason extenders feel worse than their specifications suggest.

What mesh changes

A mesh system replaces the router with a set of coordinated nodes that share one network name and one set of settings. Devices are steered between nodes as you move, and the nodes negotiate which of them carries each client, so there is no manual reconnection and no second network to choose from.

Most mesh kits also keep a separate radio for traffic between nodes, which avoids the halving that a single-radio extender suffers. That is the substantive difference between the two categories: not range, but whether the link back to the router competes with your own traffic.

Cable wherever you can

Any node or extender that can be reached with an Ethernet cable should be. A wired link removes the backhaul problem entirely, gives each node the full speed of the line, and turns a marginal setup into a stable one. Most mesh nodes accept a cable in place of the wireless link, and so do many extenders.

Running the cable is usually easier than it sounds: along a skirting board, behind furniture, or through an existing duct between floors. Where that is impossible, powerline adapters are the next option, with the caveat that their performance depends on the wiring in the walls and varies from house to house.

Before buying anything, try the cheapest fix: move the router. Out of a cupboard, off the floor, away from the metal and the mirror, and closer to the middle of the home. A surprising share of dead zones disappear at that point.