Network Repair · October 23, 2026 · ComputerKing Team

Home WiFi Dead Zones: Test First, Reposition Second, Then Choose an Extender, Mesh or Wired Access Point

Living room fast, far bedroom at one bar? Test wired first, reposition second, then choose an extender, Mesh or wired access point by whether you can run a cable.

Key Summary

Home WiFi dead zones are usually not caused by slow broadband itself, but by the signal not reaching that spot. Run a wired speed test first to separate line problems from coverage problems, then fix placement, and only then choose a solution based on whether you can run a cable.

Introduction

Have you ever had fast internet in the living room, but only one bar of signal in the farthest bedroom, with videos constantly buffering and video calls constantly dropping? That is what people generally mean by a WiFi dead zone. A dead zone does not have to mean zero signal. A signal so weak that it cannot be used, or one that keeps dropping, also counts as a dead zone.

This guide covers three things: how to tell whether the problem is the line or the coverage, how to improve coverage with free placement and settings checks, and how to choose between an extender, a Mesh system and a wired access point for your own home. This guide does not quote prices for specific equipment, because prices vary by model and supplier and require an individual quotation. It also does not ask you to open up equipment or alter the incoming line. Steps involving lines or hardware replacement should be handled by qualified people.

1. What Causes Dead Zones? Four Causes

Dead zones are usually not caused by a single factor. Several factors work together. Knowing how to separate the causes is the first step to fixing the right one.

First, distance. The farther the distance, the weaker the signal. If the router sits at one end of the living room and the farthest bedroom is at the other end of the flat, the signal has already lost a great deal by the time it arrives. Hong Kong flats are often long and narrow, with the living room at one end and the bedrooms at the other, so the far bedroom is especially likely to become a dead zone.

Second, walls and floors. The signal has to pass through walls and floors to reach its destination. The thicker the wall and the denser the floor slab, the greater the loss. Concrete walls and metal structures inside walls block the signal particularly well. Multi-storey homes add another factor: the signal also has to travel between floors, and placement that works for one floor may not be enough.

Third, interference. Some home appliances and equipment interfere with WiFi. Manufacturer guidance specifically mentions keeping the router away from microwave ovens, televisions and other high-powered appliances, as well as metal objects. A microwave oven in use interferes noticeably with the 2.4 GHz band, so a router placed near a kitchen or beside large metal appliances will have reduced coverage.

Fourth, channel congestion. When too many nearby networks use the same channel, they get in each other's way. In dense Hong Kong housing, dozens of WiFi networks on one floor are not unusual, and congestion is more noticeable on the 2.4 GHz band because it has fewer channels. Congestion does not make the signal bars disappear directly, but it slows real speeds and raises latency, so it feels like "there is signal but nothing works".

A practical rule for separating causes is to start with the cheapest and simplest checks, and not to assume at the outset that new equipment is needed. The separation test in the next section exists to narrow down the range of causes.

2. Step One: A Wired Speed Test Separates Line Problems from Coverage Problems

Before buying equipment, the most important step is separation: is the problem with the incoming line or the router itself, or is it purely a coverage problem? The method is simple. Connect a computer directly to the router with a network cable, then run a speed test. The purpose is to remove WiFi itself from the picture and see whether the incoming speed and the router itself are normal.

Two points matter before testing. First, while testing, other devices in the home should pause heavy traffic such as downloads and high-definition video, or the result will be shared with other devices. Second, test several times rather than relying on a single result, and check whether the speed is consistently slow at different times.

Table 1: Wired Speed Test Separation Table

How to use this table: fill in the first two columns with real test results, then read across to the reading column. If the wired test next to the router is already slow, buying Mesh or an extender will not help, because the problem is not coverage. This separation step is free, but it can prevent buying the wrong solution.

If the separation result confirms a coverage problem, the placement and band checks in the next section are the next step. All of these steps are free and should be tried before buying equipment.

3. Step Two: Placement and Bands, Free but Most Effective

Placement: Central, Open, Table or Shelf Height

Manufacturer placement guidance is consistent on the core principles: put the router near the centre of the home, in an open position, at about table or shelf height, not on the floor. TP-Link's official placement guidance states that a router placed near the centre of a room spreads its signal evenly in all directions, while a router against an outside wall will be noticeably weaker on the other side of the home. On height, the guidance recommends a moderate height on a table or shelf, so the signal sits at roughly the same level as most devices, not on the floor.

Work through this placement checklist item by item:

• Position: As close to the centre of the home as possible, not against an outside wall or tucked into a corner.
• Height: Table or shelf height, not on the floor, and not inside a cabinet. Cabinet doors and panels block the signal, and manufacturer guidance states explicitly that placing a router inside a cabinet greatly reduces coverage.
• Surroundings: Away from microwave ovens, televisions and large metal appliances, not beside a metal cabinet or a fish tank.
• Antennas: For a single floor, vertical antennas are generally fine. For multi-floor coverage, manufacturer guidance suggests angling the antennas at about 30 degrees so the signal travels between floors more easily. After repositioning, test again in the dead zone rather than guessing.
• Heat and sunlight: Do not place the router in direct sunlight. Prolonged overheating affects stability, and ventilation openings should stay clear.

After changing the placement, test it properly in the dead zone: open web pages, watch a video, and make a video call, and check whether things really improved. Signal bars are only a reference. Whether real use feels smooth is the real test.

Bands: 2.4 GHz for Far Rooms, 5 GHz for Fast Use Nearby

Many routers offer both 2.4 GHz and 5 GHz bands, and the two bands have opposite characteristics. The 2.4 GHz band reaches farther and penetrates walls better, but it is slower and more congested. The 5 GHz band is faster and less interfered with, but its range is shorter and it penetrates walls worse. The 6 GHz band offers higher capacity but even shorter range, and not every device supports it.

Practical rules for choosing a band:

• Far rooms, or spots separated by several walls: Use 2.4 GHz. Stability comes first. It is slower, but at least it connects.
• Near the router, for high-speed use: Use 5 GHz, for example watching high-definition video or making video calls next to the router.
• Devices that move around the home: Watch whether they drop when switching bands. Seamless roaming in a Mesh system exists to handle exactly this case.

On channels, the usual practice for 2.4 GHz is to use channels 1, 6 and 11, the three non-overlapping channels, to avoid colliding with neighbours' networks. If there are many networks nearby, a WiFi analyser app on a phone can show which channel is least used, and the channel can then be set manually in the router's management page. Before changing a channel, note the original setting so it can be restored if something goes wrong. On firmware, check regularly for new firmware, follow the manufacturer's instructions when updating, and do not cut the power during an update.

4. Step Three: Extender, Mesh or Wired Access Point

Once placement and band checks have been tried and the dead zone remains, it is time to consider buying equipment. Before choosing, answer one decision question first: can an Ethernet cable be run to the dead zone? The answer to this question largely decides which solution fits best.

A signal extender suits a single small dead zone. An extender is simple and needs no cabling, but two limits matter. First, because an extender transmits and receives on the same radio in turn, throughput roughly halves and latency rises. Second, placement matters a great deal. It must sit between the router and the dead zone, not inside the dead zone itself. If the extender itself cannot receive a good signal, what it amplifies will not be good either.

A Mesh system suits homes where several rooms or several floors have dead zones. Mesh uses several nodes working together under one network name, so devices can roam seamlessly as they move around the home. Mesh can run in AP or bridge mode together with the broadband provider's router. Before installation, decide which unit acts as the router, and put the other in AP or bridge mode, to avoid two units acting as routers at once. That situation creates double NAT, which can affect port forwarding, games consoles and some smart home devices.

A wired access point suits cases where an Ethernet cable can be run to the dead zone. A wired access point uses a wired backbone, so there is no wireless relay speed loss, and it is the more stable of the three approaches. The drawback is that an Ethernet cable must be run first, and in a finished flat the cable route may need separate planning.

Table 2: Three-Solution Decision Table

How to use this table: answer "can a cable be run?" and "how many dead zones are there?", then read across to the suggested direction. On prices, different models and suppliers differ greatly. This guide does not quote specific prices. Actual charges require an individual quotation and are subject to the supplier's published terms.

5. Common Mistakes: Five Things Not to Do

Mistake 1: Buying equipment before separating the fault. Buying Mesh or an extender straight away, then discovering that the wired test next to the router is already slow, means the problem was never coverage. What to do instead: run the wired speed test separation in Section 2 first, and only choose a solution once a coverage problem is confirmed.

Mistake 2: Putting the router inside a cabinet. Hiding the router in a TV cabinet or a metal cabinet for tidiness lets the cabinet doors and panels block the signal. What to do instead: take it out, place it in an open spot at table height, and test again in the dead zone.

Mistake 3: Putting an extender inside the dead zone. An extender that cannot itself receive a signal cannot amplify anything useful. What to do instead: place it between the router and the dead zone, at a middle point that still receives a reasonable signal, to act as a relay.

Mistake 4: Two units acting as routers at once. When the broadband provider's router and a Mesh system both act as routers, double NAT results, affecting port forwarding, games consoles and some smart home devices. What to do instead: decide before installation which unit acts as the router, and put the other in AP or bridge mode.

Mistake 5: Judging by signal bars alone, not by real use. Signal bars may be full while web pages still load slowly, because the cause may be channel congestion or interference. What to do instead: judge by real use: opening web pages, watching video, and making video calls, and checking whether they really run smoothly.

6. Prevention and Regular Checks: Keeping Dead Zones Away

Once a dead zone is fixed, the following habits reduce the chance of it returning. They fall into two groups: things to do right away, and things to do regularly.

Do right away:

• Once the router's position is fixed, do not put it back inside a cabinet for tidiness.
• After adding large metal appliances or large furniture, check whether anything now blocks the straight path between the router and the dead zone.
• When a new device joins the home, check which band it connects to: far-room devices on 2.4 GHz, nearby high-speed devices on 5 GHz.

Do regularly:

• Check for firmware updates from time to time, follow the manufacturer's instructions when updating, and do not cut the power during an update.
• When neighbours' networks change a great deal, or many new networks appear nearby, check channel congestion again.
• After moving home, renovating, or changing the router, repeat the separation and placement checks rather than assuming the old settings still apply.

Table 3: Regular Check Checklist

Frequently Asked Questions

Q: What most commonly causes home WiFi dead zones?

A: Distance, thick walls and floors, appliance interference, and channel congestion are all common causes. Layout and building materials worsen coverage, and two flats that look similar can have completely different dead zones. Start with a wired speed test next to the router to separate a line problem from a coverage problem, then decide the next step.

Q: How do I tell whether it is a line problem or a coverage problem?

A: Connect a computer directly to the router with a network cable and run a speed test next to it. If it is slow there too, it is a line or router problem. If it is fast there but slow in other rooms, it is a coverage problem. Pause other devices' heavy traffic while testing, and test several times before deciding rather than relying on a single result.

Q: Where should the router be placed?

A: Near the centre of the home, in an open position, at about table or shelf height, not on the floor, and not inside a cabinet. Keep it away from microwave ovens, televisions and large metal appliances. For a single floor, keep the antennas vertical. For multiple floors, the antennas can be angled at about 30 degrees. After repositioning, test again in the dead zone.

Q: Should a far room use 2.4 GHz or 5 GHz?

A: A far room should use 2.4 GHz, because it reaches farther and penetrates walls better, even though it is slower and more congested. Nearby high-speed use should use 5 GHz, because it is faster and less interfered with, but its range is shorter and it penetrates walls worse. The usual practice for 2.4 GHz is to use channels 1, 6 and 11, the three non-overlapping channels, to avoid colliding with neighbours' networks.

Q: Where should an extender be placed?

A: An extender must sit between the router and the dead zone, not inside the dead zone itself. An extender suits only a single small dead zone, and because it transmits and receives on the same radio in turn, it roughly halves throughput and raises latency. After placing it correctly, test with real use in the dead zone to check whether things really improved.

Q: When should I use Mesh, and when a wired access point?

A: Ask first whether an Ethernet cable can be run to the dead zone. If it can, use a wired access point, with a wired backbone and no wireless relay speed loss. If it cannot, use Mesh, which suits homes where several rooms or several floors have dead zones. With Mesh, avoid two units acting as routers at once, or double NAT will result.

Q: What free steps can I try before buying equipment?

A: Try moving the router, restarting equipment, updating firmware, and switching to a less congested channel. Placement is the free first step, and band and channel checks cost nothing either. Only after all of these steps, with the dead zone still present, should a solution be chosen using the decision table in Section 4. Prices vary by model and supplier and require an individual quotation.

Q: Why is the internet still slow when the signal bars are full?

A: Signal bars show signal strength only, not real speed. Channel congestion, interference, and many devices sharing one network can all make a full-bar signal feel slow. Judge by real use: opening web pages, watching video, and making video calls. If a full-bar signal is still slow, check channel congestion, or run a wired speed test next to the router for comparison.

Summary

For home WiFi dead zones, the order of work matters. First, separate the fault: run a wired speed test next to the router. If it is slow there too, it is a line or router problem. If it is fast there but slow in other rooms, it is a coverage problem. Second, fix placement: central, open, table height, not inside a cabinet, away from large metal appliances. On bands, far rooms use 2.4 GHz and nearby high-speed use uses 5 GHz. Third, choose a solution: a wired access point if an Ethernet cable can be run, Mesh if it cannot, and an extender only for a single small dead zone on a tight budget, placed in the middle, not inside the dead zone itself.

When to stop and ask someone qualified to look: when the wired test next to the router is already slow, when the incoming line is suspected, or when cabling or hardware replacement is needed. Do not open equipment or alter lines yourself in those cases. On prices, actual charges require an individual quotation and are subject to the supplier's published terms.

Sources

• TP-Link official placement guidance: central position, table height, antenna angles, distance from appliances, not inside a cabinet (https://www.tp-link.com/es/support/faq/455/, checked 2026-10-23)
• TP-Link official placement article: consider placement before buying Mesh or an extender, and how walls and interference affect coverage (https://www.tp-link.com/us/blog/87/6-tips-on-where-to-place-your-wireless-router-for-the-best-signal-coverage/, checked 2026-10-23)
• ComputerKing internal article: Home WiFi Keeps Dropping? Router Placement + Settings Complete Guide (/blog/wifi-network-optimization-guide)
• ComputerKing internal article: How to Choose a Home Router? 2026 Hong Kong Broadband Router Buying Guide (/blog/router-buying-guide-hong-kong-2026)

Related Articles

• Home WiFi Keeps Dropping? Router Placement + Settings Complete Guide (/blog/wifi-network-optimization-guide)
• How to Choose a Home Router? 2026 Hong Kong Broadband Router Buying Guide (/blog/router-buying-guide-hong-kong-2026)