Wi-Fi extender vs mesh vs powerline: which fixes a dead zone?
One room, the loft or the garden office never gets decent Wi-Fi, and the shop offers three different boxes to fix it. They work in very different ways, and the right one depends mostly on how the new box gets its data <i>back</i> to the router.
How each one gets data back to the router
| Extender (repeater) | Mesh system | Powerline adapters | Wired access point | |
|---|---|---|---|---|
| Link to the router | Wi-Fi, often on the same radio it serves you on | Wi-Fi (a dedicated band on tri-band kits) or Ethernet | The mains wiring in your walls | Ethernet cable |
| Typical real speed far from the router | About half of what it receives (single-band), better on dual-band | Good, best with wired or dedicated backhaul | Anything from 20 to 300+ Mbps, depends on wiring | Full speed |
| Network name | Often a second name, like Home_EXT | One name everywhere, devices are steered between units | Your router's Wi-Fi plus a cable socket, or its own Wi-Fi | Can share your name |
| Cost | Lowest | Highest (two or three units) | Middle | Low, if you can run a cable |
| Best for | One room just past good coverage | Whole houses, several dead zones, lots of devices | Thick walls, extensions, garden offices on the same electrics | Anywhere a cable can reach |
Why an extender halves the speed
A basic single-band extender has one radio. Every piece of data has to be received from the router and then sent again to your laptop on the same channel, and Wi-Fi devices on one channel take turns to talk. So the extender spends half its airtime listening and half repeating. A dual-band extender that talks to the router on 5 GHz and to you on 2.4 GHz (or the other way round) avoids most of that loss.
Placement matters more than the model: put an extender roughly halfway, where it still gets a strong signal from the router. Plugged in right inside the dead zone, it can only repeat a weak signal.
Mesh: why it costs more and when it is worth it
Mesh units coordinate as one network with one name, and they hint to phones and laptops when to move to a closer unit. That hand-over is called roaming, and Wirebook has a playable version of it: why the video call freezes when you walk to the kitchen. Tri-band kits keep a third radio just for unit-to-unit traffic (the backhaul), and almost every mesh system lets you plug units together with a cable for the best result. Details in mesh Wi-Fi backhaul and placement.
Powerline: the honest version
- The box numbers (AV600, AV1000, AV2000) are the theoretical top speed of the wiring link, not what you will get. Real throughput is often a quarter of that or less.
- Plug each adapter straight into a wall socket. Extension leads and surge protectors filter the signal.
- Both adapters should be on the same electrical installation. Across different consumer units or a separate garage supply, speed can collapse.
- Chargers, fridges, washing machines and LED drivers add electrical noise, so speed can change during the day.
- Test before you rely on it: copy a big file or run a speed test over the adapter with a cable. If it is unstable, try a different pair of sockets.
Other ways to get a wire there
If your home has TV coax sockets, MoCA adapters carry Ethernet over that cable and are usually faster and steadier than powerline. A flat Ethernet cable under a carpet edge or along a skirting board is cheap and beats every wireless option. Any old router can be set to access point mode at the end of that cable.
Try these free fixes first
- Move the router out of a cupboard, away from the TV and off the floor, as high and central as you can.
- Use 5 GHz near the router and 2.4 GHz for range: 2.4 GHz vs 5 GHz.
- Pick a quieter channel: best Wi-Fi channel.
- Check the problem is really coverage and not your plan: Mbps vs MB/s and why speed tests read low.
Why walls matter so much is explained with a picture in Wirebook: how Wi-Fi gets through walls.
Related
Wired to another room without drilling (flat cable, MoCA) · Which Ethernet cable to run · What is a good ping, jitter and packet loss? · Internet lags when someone downloads (bufferbloat) · Mbps vs MB/s: internet speed explained · Mesh Wi-Fi backhaul and placement · Wi-Fi keeps disconnecting
Questions
Do Wi-Fi extenders slow down your internet?
A single-band extender usually halves the speed for devices connected to it, because it receives and resends everything on the same radio. Devices near the router are not slowed. Dual-band extenders and mesh with a dedicated backhaul lose much less.
Is mesh Wi-Fi better than an extender?
For a whole house, yes: one network name, devices are steered to the closest unit, and tri-band or wired backhaul keeps speeds up. For one weak room, a well-placed extender can be enough and costs far less.
Is powerline better than Wi-Fi?
Sometimes. It goes through thick walls and to outbuildings on the same electrics, but real speeds vary with your wiring and electrical noise, and it can be slower than a good mesh system.
Can I plug a powerline adapter into an extension lead?
It is not recommended. Extension leads and surge protectors filter the signal and can cut the speed a lot. Plug adapters straight into a wall socket.
What is the best way to get Wi-Fi in a garden office?
A buried or outdoor-rated Ethernet cable to an access point is best. Without one, try powerline if the office shares the house's electrics, or an outdoor mesh unit with a clear line of sight.
Published .