The short answer
Put the extender roughly halfway between your router and the dead zone, at the last point where the router’s own signal is still strong (about -65 dBm or three bars). Not in the dead zone. Not next to the router. Elevated, out in the open, and at least a metre away from microwaves, TVs, fish tanks and metal shelving.
Almost every complaint that starts with “my extender did nothing” ends in the same place: the extender is plugged into a socket in the room that had the problem. It feels like the obvious spot, and it is the one spot that cannot work. An extender does not create signal. It listens to whatever your router sends it and rebroadcasts that. If it can barely hear the router, it rebroadcasts a weak, lossy copy, and you end up with full bars and nothing loading, which is more frustrating than no signal at all.
How an extender actually splits your bandwidth
A single-band extender talks to the router and to your laptop on the same radio, taking turns. That halves throughput before anything else goes wrong. A dual-band or tri-band extender keeps one band as a dedicated backhaul to the router, so the penalty is much smaller. This matters for placement: on a cheap single-band unit, every bit of signal loss between the router and the extender gets doubled down the line. On a tri-band unit you have more room for error, but the same rule still applies.
Find the halfway point properly
Install a signal meter on your phone
On Android, WiFiman, Network Analyzer or WiFi Analyzer all show signal strength in dBm. On iOS, Apple restricts Wi-Fi scanning, so use AirPort Utility with Wi-Fi Scanner enabled in Settings, or borrow an Android phone for ten minutes. You want the number in dBm, not the bar graphic, because bars hide a huge range.
Walk the route from router to dead zone
Stand still for five seconds at each point and note the reading. Signal strength is negative: -40 dBm is excellent, -60 dBm is good, -70 dBm is marginal, -80 dBm is unusable. Walk the natural path the signal takes, through doorways rather than through the thickest walls.
Mark the last good spot
Find the furthest point where you still read about -65 dBm or better. That is your extender location. It will usually feel too close to the router. It is not.
Check there is a socket there
If the only mains socket at that point is behind a sofa or inside a cabinet, move to the nearest open socket that still reads better than -67 dBm. A short extension lead to get the extender out into the open is worth more than the ideal spot behind furniture.
Set it up and re-measure in the dead zone
Connect the extender, then walk back to the problem room and measure the extender’s network. If you are not seeing at least a 15 dBm improvement over the old reading, move the extender one room closer to the router and try again.
Run a real speed test, not just a signal check
Signal strength and throughput are different things. Run a speed test on a phone in the dead zone before and after. A good result is roughly 40 to 60 percent of what you get standing next to the router. Much less than that means the backhaul link is struggling.
Most extenders have a signal indicator LED that tells you whether the link to the router is good, fair or poor. It is not as precise as a dBm reading, but if it is amber or red where you have placed the unit, you already have your answer: move it closer.
Placements that quietly ruin performance
- On the floor. Radio waves spread outward and downward from an antenna; floor level wastes half the pattern into the concrete. Chest height or above is the target, which usually means an upper socket or a shelf.
- Behind or beside a TV. A large screen is a sheet of metal and shielding, and the surrounding kit throws off interference. This is the single most common bad spot because it is where the free socket usually is.
- In the kitchen near the microwave. Microwaves leak in the 2.4 GHz band by design. Every time someone reheats a coffee, the link drops.
- Inside a media cabinet or cupboard. Enclosed wood is tolerable, enclosed metal is fatal.
- Next to a mirror, fish tank or radiator. Water and metal both absorb 5 GHz aggressively. A large aquarium between two rooms can cost you 20 dBm on its own.
- Directly beside the router. It will show a perfect link and extend your coverage by almost nothing.
The wall-thickness problem nobody mentions
The reason the halfway rule needs adjusting in older houses is that walls are not equal. A stud wall with plasterboard costs you around 3 to 5 dBm. A solid brick internal wall costs 8 to 15 dBm. Reinforced concrete, foil-backed insulation and old lath-and-plaster with metal mesh can cost 20 dBm or more, which is enough to kill a 5 GHz link outright. If your dead zone is behind one of those, the halfway point is not geometric halfway, it is wherever the signal actually survives, and that may be right at the doorway.
Where possible, place the extender so that it has line of sight through a doorway to the router rather than through the wall. Open plan is your friend here. Going up or down a floor is usually easier than going through two brick walls, because floors are often timber.
Band settings that make placement easier
If your extender lets you choose which band to use for the backhaul, pick 5 GHz for the link to the router when the extender is close enough to hold it, and rebroadcast on both bands. 5 GHz carries much more data but passes through walls poorly, so it is the right choice for a short, clean backhaul and the wrong choice for a long one. If your extender is two brick walls away, force the backhaul to 2.4 GHz and accept the lower ceiling, because a reliable slow link beats an intermittent fast one.
Also give the extended network the same SSID and password as the main network if the extender supports it, so devices roam between them. If it insists on creating a separate network name, phones will cling to the weaker original network long after you have walked into the extended zone, and you will blame the extender for a problem it is not causing.
If your broadband is faster than about 200 Mbps, a single-band extender will become the bottleneck no matter where you put it. At that point a mesh system or a powerline adapter with a wired backhaul is the honest answer rather than better placement.
When placement is not the problem
Move the extender twice, measure properly, and if the numbers barely change, the fault is somewhere else. Check whether the router itself is in a cupboard by the front door, which is where installers love to put them and where they perform worst. Check whether the router firmware is current. Check the channel: in a block of flats, 2.4 GHz is often so congested that no amount of repeating helps, and switching the router to channel 1, 6 or 11 with the least neighbours on it does more than any extender.
And check how many devices you are actually running. Cheap extenders often cap out at around 20 to 30 connected clients, and a modern home with smart bulbs, plugs, cameras and speakers hits that number faster than people expect.
Should the extender go halfway by distance or halfway by signal?
By signal, always. Distance is only a rough proxy. Two rooms of open hallway cost far less than one reinforced wall, so measure in dBm and put the extender at the last point that still reads about -65 dBm or better.
Can I use two extenders in a chain to reach further?
You can, but daisy-chaining halves throughput again at each hop and adds latency, so the second extender usually delivers a connection too slow to be useful. If one extender does not reach, a mesh system with a dedicated backhaul is the better spend.
Why do I get full bars but nothing loads?
That is the classic sign of an extender placed too far from the router. Your phone sees a strong signal from the extender, but the extender itself has a poor link back to the router, so packets are being lost upstream. Move the extender closer to the router.
Is an extender better than a powerline adapter?
If your walls are thick or the dead zone is far away, a powerline adapter is usually better because it carries the data over your mains wiring instead of through the walls. It struggles on old wiring and across separate consumer units, but when it works it is more stable than a long radio hop.
Does the extender need to be on the same floor as the router?
No. Signal often travels better between floors than through masonry walls, especially with timber floors. Try the spot directly above or below the router before ruling it out.
The five-minute version
Measure with a dBm app, walk from the router towards the dead zone, and plug the extender in at the last point where you still read about -65 dBm. Get it up off the floor and away from metal, glass, water and the microwave. Match the network name to the main network so devices roam properly. Then re-test in the dead zone. If the improvement is under 15 dBm, move one room closer to the router and repeat. That is the whole method, and it fixes the overwhelming majority of extenders that “did nothing”.
