Short answer
Wifi is weakened mainly by walls, floors and insulation with a metal layer. A more powerful router does not fix that, because the problem lies between the transmitter and the receiver. What does work is a second point closer by, preferably fed by a cable. A network cable to the loft or the shed is the most lasting solution.
Who this article is for Anyone whose wifi does not reach everywhere. You can measure it yourself with your phone; running cables is work I do.
Why the signal drops out
Wifi is radio, and radio gets weaker because of what is in between. What costs the most:
| What is in between | Effect on the signal |
|---|---|
| Plasterboard wall | small |
| Brick wall | noticeable |
| Reinforced concrete floor | large |
| Insulation with foil or a metal layer | very large, acts like a mirror |
| Underfloor heating in the floor | large |
| Large mirror or metal cabinet | large locally |
That is why a modern, well insulated home often has worse wifi than a draughty house from 1930.
Why a more powerful router rarely helps
The router may transmit more strongly, but your phone does not transmit back any more strongly. A connection has two sides, and the weaker one decides the result. That is why a more expensive router in the same position rarely makes a noticeable difference.
What does work
A second point closer by. An access point where the signal is needed.
An access point fed over wifi halves the speed; with a cable it does not.
Feed that point with a cable. An access point that is itself connected over wifi halves the speed and makes the dropouts worse. With a network cable to it, the problem is solved for good.
The router in a better place. Not in the meter cupboard under the stairs, but central in the home and not on the floor.
What works so-so
Plug-in wifi extenders. They double the coverage but halve the speed, and devices often stay stuck to the wrong point.
Powerline over the mains wiring. Sometimes works surprisingly well and sometimes not at all, depending on how the circuits run. Across different phases it usually works badly.
Mesh without a cable. Better than a single extender, but it is still wifi over wifi.
Measuring with your phone
Walk through your house with an app that shows the signal strength in dBm. Rule of thumb: down to about minus 65 dBm is fine, around 75 it gets slow, below 80 it is unusable. Then you know exactly where the point needs to go.
During a renovation
Run a cable to every floor and to the shed. During the build it costs next to nothing. See running network cable and when the electrician comes in.
From my own work
In a home in Beek the wifi in the loft did not work, despite two plug-in extenders. The floor between the first floor and the loft had been done with foil insulation, and for wifi that foil is more or less a mirror. A network cable to the loft with an access point on it, and it worked everywhere, including the back garden.
When to call an electrician
- Wifi drops out in the loft, in the shed or in the garden
- You have tried extenders and it keeps dropping out
- A cable needs to go to another floor
Running a cable is usually half a day and then it is done. Request a quote.
Frequently asked questions
Does a stronger router help against poor wifi?
Rarely. Your phone does not transmit back any more strongly, and the problem lies between the transmitter and the receiver.
Do plug-in wifi extenders work?
They increase the coverage but halve the speed, and devices often stay stuck to the wrong point.
Why is wifi often worse in a new house?
Because of insulation with a foil or metal layer. For wifi it acts like a mirror.
Further reading
Access point or mesh: which to choose
Mesh is quick to set up and works reasonably well. Wired access points work better and last longer.
Fibre at home: what happens and what you need to arrange yourself
The provider brings the fibre into the meter cupboard. From there it is your network, and that is where there is most to gain.
A camera by the door or on the front of the house: what is allowed and what works
A camera on your wall may film your own property. The neighbours and the pavement are another matter.
Questions and comments
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