Why Your Wi-Fi Router Has Poor Signal in the Next Room: Technical Reasons and Fixes

Have you noticed that your internet connection is blazing fast in one room, while in the next, pages barely load, videos lag, and messaging apps refuse to send messages? The problem of a weak Wi-Fi signal through a wall is familiar to many, especially in prefabricated buildings or apartments with poor layouts. But why does this happen when the router is literally 5 meters away?

It's not always a matter of a "weak" device. More often, the culprit is physical barriers, incorrect settings, or interference from neighbors. In this article, we'll look at real reasons signal drops and we will give concrete solutions — from free (changing the Wi-Fi channel) to radical (replacing antennas or buying a repeater). Some methods will work immediately, while others will require 10 minutes of setup. Let's start with the most obvious—but often overlooked.

1. Physical barriers: how walls "eat" Wi-Fi signals

The main enemy of stable Wi-Fi is not distance, but materials through which the signal passesWaves with a frequency of 2.4 GHz (the most common range) penetrate poorly through:

• 🧱 Concrete walls (especially with reinforcement) - weaken the signal by 50-70%.
• 🪨 Brick - reduces power by 30–50% depending on thickness.
• 🚪 Metal doors - can completely block the signal (Faraday cage effect).
• 💧 Aquariums, water pipes - Water absorbs radio waves almost like metal.

For comparison, drywall or wood weaken the signal by only 5-10%. If there is a signal between the router and your device two concrete walls, power loss can reach 90% — that’s why the speed drops by 10–20 times.

How to check? Take your phone with a Wi-Fi analyzer app (for example, WiFi Analyzer (for Android) and walk around your apartment. If the signal level drops from -50 dBm to -80 dBm behind one wall, that wall is the culprit.

2. Interference from neighbors: why your router "conflicts" with other networks

In an apartment building, one Wi-Fi channel can be used dozens of routersIf they all broadcast on Channel 6 (the most popular in the 2.4 GHz range), the speed drops due to ether congestionIt's like trying to shout at a market – everyone is talking at once and you can't make anything out.

You can check the channel load in the same WiFi Analyzer or via the router's web interface (section Wireless → Channel). If the graph shows 5-10 networks on one channel, that's your problem.

Solution:

1. Go to your router settings (usually 192.168.0.1 or 192.168.1.1).
2. Search section Wireless Settings → Channel.
3. Choose the least crowded channel (in 2.4 GHz - only 1, 6 or 11).
4. Save the settings and reboot the router.

3. Router transmission power: why it may be limited

Many routers operate at a lower power level by default. Manufacturers do this to:

• 🔋 Save energy (relevant for battery-powered models).
• 📡 Comply with local regulations (in the EU and the US, restrictions are stricter than in Russia).
• 🔄 Reduce chip heating during long-term operation.

As a result, your ASUS RT-AX56U or TP-Link Archer C6 It can operate at 50% of its capacity. You can check the current level in the settings:

Advanced Settings → Wireless → Transmit Power

Optimal values:

• 2.4 GHz: 70–100% (or 20 dBm).
• 5 GHz: 50–80% (high power may overheat the chip).

What happens if I set the power to 100%?

The signal will improve briefly, but the router may begin to overheat, especially if it's in a closed cabinet. In cheaper models, this can lead to slower speeds or spontaneous reboots.

⚠️ Attention: In some countries (for example, Japan), increasing power beyond the standard values ​​is prohibited by law. There are no such restrictions in Russia, but check the documentation for your model before changing the settings.

4. Incorrect router placement: where it shouldn’t be placed

Even the most expensive router will have poor Wi-Fi performance if it's located in a "dead zone." Common mistakes:

• 🚪 Corner of the room - the signal is distributed along an arc, not uniformly.
• 🪑 Behind the furniture - cabinets, sofas and even large plants absorb waves.
• 📦 In a closed closet - metal doors block the signal.
• 🌡️ Near heat sources (batteries, stove) - overheating reduces performance.

Ideal place:

1. IN in the center of the apartment (or closer to the room where the signal is needed).
2. On height of 1–1.5 meters (on the table, shelf, not on the floor!).
3. IN open space (not behind flower pots or an aquarium).

If it is not possible to move the router (for example, the provider's cable is only in one room), use Ethernet extender or Powerline adapters (they transmit the Internet through electrical wiring).

5. Outdated firmware or hardware limitations of the router

Old routers (manufactured before 2018) often do not support modern Wi-Fi standards (802.11ac or 802.11ax), due to which:

• 📉 Speed ​​is limited 54 Mbps (instead of possible 300–1200 Mbps).
• 🔄 Frequent connection interruptions when connecting multiple devices.
• 🛑 No support MU-MIMO (simultaneous work with several clients).

How to check?

1. Check your router model (usually on the sticker on the bottom).
2. Find its specifications on the manufacturer's website (for example, tp-link.com).
3. Compare with the table:

If your router is older than 5 years, update its firmware (instructions are usually available on the brand's website). If this doesn't help, consider purchasing a new model with support. Wi-Fi 6 (For example, Xiaomi AX3600 or Keenetic Hero).

6. External interference: microwaves, baby monitors, and other Wi-Fi "enemies"

Wi-Fi operates on the same frequencies as other household appliances. The main signal thieves are:

• 🍳 Microwave ovens — work on 2.45 GHz, which coincides with Wi-Fi channels 11–14. A microwave oven turned on can completely jam the network.
• 📞 DECT cordless phones - use the range 1.8–1.9 GHz, but create background noise.
• 👶 Baby monitors - many models work on 2.4 GHz and constantly "clog" the airwaves.
• 🚗 Wi-Fi dash cams — may create local interference if located near a router.

How to fight:

• Turn off unnecessary devices during the test (e.g. baby monitor).
• Move the router away from the microwave (at least 2 meters).
• Move sensitive devices (such as IP cameras) to 5 GHz, if they support this range.

⚠️ Attention: If you have smart home with sensors on 2.4 GHz (For example, Xiaomi Aqara), their signals can also conflict with Wi-Fi. In this case, separating the networks will help: one for smart home devices, another for laptops and phones.

7. Signal Boosting Solutions: From Free to Radical

If all the above methods do not help, it is time to consider hardware improvementsHere are the options from cheapest to most expensive:

1. Changing antennas (500–1500 ₽).

   Many routers come with weak antennas. 3–5 dBiReplace them with 7–9 dBi (For example, TP-Link TL-ANT2409A). This will increase the signal by 20-40%.

2. Wi-Fi repeater (1000–3000 ₽).

   A "repeater" device connects to your network and rebroadcasts the signal further. Cons: Speed ​​drops by 30-50% due to double data transfer.

3. Mesh system (5000–15000 ₽).

   A set of 2-3 access points (eg Tenda Nova MW6), which create a unified network without speed loss. Ideal for large apartments.

4. Cable installation + additional router (2000–5000 ₽).

   The most reliable solution: pull Ethernet cable into the far room and connect the second router in mode Access Point.

Advice: Please check your router before purchasing. WDS (wireless connection with a repeater) or MeshSome budget models (for example, D-Link DIR-300) do not know how to work in such networks.

FAQ: Frequently asked questions about weak Wi-Fi signals

Is it possible to boost the signal without buying new equipment?

Yes! To begin with:

1. Change the Wi-Fi channel to a free one (section 2 of the article).
2. Change the location of the router (section 4).
3. Update the firmware (section 5).
4. Increase the transmit power in the settings (section 3).

These actions solve the problem in 70% of cases.

Why is there a signal on my phone but not on my laptop?

Possible reasons:

• The laptop only works on 2.4 GHz, and the router is configured to 5 GHz (or vice versa).
• An outdated Wi-Fi adapter in the laptop (for example, 802.11n against 802.11ac router).
• The adapter driver has not been updated for years (check in Device Manager).

Solution: Enable it in your router settings. compatibility mode (Legacy Mode) or update the driver on your laptop.

Does putting foil behind the router help boost the signal?

Partially. Foil works as reflector — it redirects the signal in one direction, but does not amplify it. Effect:

• ✅ The signal will become stronger in one side (for example, into the corridor).
• ❌ In other directions, coverage will deteriorate.

It is better to use specialized ones reflectors (For example, Wi-Fi Blaster), but their effect is also limited.

Which router is best for a large apartment?

Optimal options in terms of price/quality ratio (2026):

Model	Ranges	Max. speed	Price (≈)	Peculiarities
Xiaomi AX3600	2.4 + 5 GHz	2976 Mbps	5000 ₽	6 antennas, Mesh, Wi-Fi 6
TP-Link Archer AX23	2.4 + 5 GHz	1800 Mbps	3500 ₽	Budget Wi-Fi 6, good for a 3-room apartment
Keenetic Hero	2.4 + 5 GHz	3000 Mbps	8000 ₽	Yota and Mesh support, built-in antivirus

For apartments >100 m² it is better to consider Mesh systems (For example, Tenda MW6 or ASUS ZenWiFi XD4).

Why is the speed so different between cable and Wi-Fi?

This is normal! Speed ​​losses during wireless transmission are associated with:

• Interference (section 2 of the article).
• Distance (every 3 meters - -10% speed).
• Number of devices (the router shares the channel between all clients).
• Protocol (For example, 802.11n the maximum will be 300 Mbit/s, even if the cable is 1 Gbit/s).

To reduce the difference:

1. Connect critical devices (PC, Smart TV) via Ethernet.
2. Use range 5 GHz for high-speed tasks (it is less loaded).
3. Limit bandwidth-hungry devices (such as torrent clients) QoS in the router settings.