The short answer
Move the router first, because height and position change vertical coverage more than anything else you can do for free. Routers radiate outwards rather than upwards, so a router on the ground floor at one end of the house leaves the opposite upstairs corner in shadow. If that is not enough, one mesh node upstairs, ideally wired, fixes it properly.
Wi-Fi antennas produce a doughnut-shaped pattern: strong outwards, weak directly above and below. Combine that with a floor made of timber, plaster and sometimes foil-backed insulation, and the upstairs of a house is genuinely harder to cover than the same distance horizontally.
Step 1: move the router
Get it out of the cupboard
The cupboard by the front door is where installers put routers and where they perform worst. A short extension of the incoming line lets you move it.
Raise it off the floor
To at least desk height, and higher if you can. A router on the floor wastes a large part of its pattern into the ground.
Move it towards the centre of the house
Both horizontally and, if possible, upwards. A router on a high shelf in a central room covers two floors far better than one in a corner.
Adjust the antennas if it has them
A mix of vertical and angled antennas covers both floors better than all vertical, which favours the floor it is on.
Move it away from metal, mirrors and water
Radiators, fish tanks and large mirrors all attenuate the signal noticeably.
These cost nothing and frequently resolve the problem entirely. Measure with a Wi-Fi analyser app upstairs before and after so you know whether it helped rather than guessing.
Step 2: understand what the floor is made of
- Timber floors with plasterboard ceilings: the easy case, and signal passes reasonably well.
- Concrete floors: common in flats and newer houses, and they attenuate heavily.
- Foil-backed insulation between floors, which is close to a solid barrier for Wi-Fi.
- Underfloor heating, where metal pipes or heating mats form a partial screen.
- Metal ductwork or steel joists, which create sharp shadows.
If the upstairs signal is poor in a way that no repositioning improves, the construction is probably the reason, and the answer is a device upstairs rather than a stronger signal from downstairs.
The stairwell is usually the best path between floors, because it is the one place with no floor in the way. A router positioned so that the stairwell is in its line of sight covers upstairs far better than one on the other side of the house, and this is worth experimenting with.
Step 3: band and channel
5GHz carries more data and passes through floors poorly. Upstairs, a device may be clinging to a weak 5GHz signal when a strong 2.4GHz one would serve it better.
Splitting the bands into separate network names and joining upstairs devices to the 2.4GHz one is a useful test. It trades speed for stability, which for a phone or a television upstairs is usually the right trade.
Also check the 2.4GHz channel is one of 1, 6 or 11, with the fewest neighbours on it, and set the channel width to 20MHz. In a crowded area that matters more than transmit power.
Step 4: add a device upstairs
When placement has been exhausted, the answer is hardware upstairs. In increasing order of effectiveness:
- A Wi-Fi extender, placed at the top of the stairs where the downstairs signal is still decent. Cheap and adequate for one or two devices.
- A powerline adapter with a Wi-Fi access point, which carries the signal over the mains and creates a proper access point upstairs. Performance depends on the wiring and it is often good.
- A mesh node, which handles roaming properly and is the right answer for whole-house coverage.
- A wired access point or mesh node, connected by an Ethernet cable run up the stairs. This is the best possible outcome and, with flat cable along the skirting, more achievable than people expect.
The single Ethernet cable is worth emphasising. A wired node upstairs performs like the router itself, and one cable transforms a house’s coverage in a way no amount of wireless repeating can match.
If you have coaxial television cabling running upstairs, adapters exist that carry network data over it. That is a genuine alternative to running new Ethernet in houses where the coax is already where you need it, and it performs far better than a wireless hop.
Step 5: check what is actually slow
Before rebuilding the network, confirm the problem is coverage. Test the speed standing next to the router, then upstairs, using the same device. If the router itself is delivering poor speeds, no amount of coverage work will help, and the issue is the connection or the router rather than the floor between you.
Also check whether one device is the problem rather than the location. A laptop with an old wireless adapter will be slow upstairs while a modern phone is fine in the same spot.
Why is Wi-Fi so much worse upstairs?
Router antennas radiate outwards rather than upwards, and floors attenuate the signal. A router on the ground floor in a corner leaves the opposite upstairs corner in the weakest part of its pattern.
Will moving the router really help?
Frequently, and it costs nothing. Getting it out of a cupboard, off the floor and towards the centre of the house, ideally with the stairwell in view, often resolves the problem entirely.
Should upstairs devices use 2.4GHz?
Often yes. 5GHz passes through floors poorly, and a stable 2.4GHz connection beats an intermittent 5GHz one for phones and televisions.
Extender or mesh for upstairs?
An extender for one room on a budget. A mesh node for proper coverage and roaming. A wired mesh node is best of all and needs one Ethernet cable up the stairs.
Can foil insulation block Wi-Fi?
Yes, substantially. Foil-backed insulation between floors acts close to a solid barrier, and in that case no repositioning downstairs will fix upstairs coverage.
The order
Move the router up, out and towards the centre, ideally with the stairwell in view, and measure before and after. Split the bands and put upstairs devices on 2.4GHz if 5GHz is marginal. Then add a device upstairs, preferring a mesh node over an extender, and wire it if you possibly can, because one cable up the stairs does more than any amount of wireless tuning.
