Wi-Fi connectivity has become an essential part of our lives. We rely on Wi-Fi networks at home, work, and in public places to access the internet and stay connected. However, sometimes you may find yourself in a Wi-Fi “dead zone” where the signal is weak or nonexistent. There are many factors that can interfere with or block Wi-Fi signals.
How Wi-Fi Signals Travel
To understand what can disrupt a Wi-Fi connection, it helps to first understand how Wi-Fi signals travel. Wi-Fi devices like routers or modems broadcast wireless signals using radio frequency (RF) waves. These waves travel through the air and can pass through walls and other solid objects to reach Wi-Fi enabled devices like laptops, smartphones, and more. The further the signal travels from the router, the weaker it becomes. Wi-Fi networks operate on specific frequency bands such as 2.4GHz and 5GHz. On these bands, there are multiple Wi-Fi channels that keep signals separated.
Obstacles and Interference
As Wi-Fi signals radiate outward from the router, they encounter obstacles that cause interference or degrade the signal. Common culprits that can block or weaken Wi-Fi networks include:
- Thick walls and floors: Dense materials like concrete, brick, and metal can absorb and dissipate Wi-Fi signals. The signal has to pass through fewer walls and ceilings for the best coverage.
- Large appliances: Items with electric motors or heavy shielding like refrigerators, stoves, microwaves, aquariums, and even desktop computers can block Wi-Fi signals.
- Distance: Wi-Fi range is limited, often to about 100 feet indoors. Placing the router in a central location will maximize coverage area.
- Interference from other electronics: Other wireless signals and electronics operating on the 2.4GHz or 5GHz bands can cause interference with Wi-Fi networks.
- Physical obstructions: Mountains, hills, thick foliage, buildings, and other physical barriers between the router and connected device will degrade or block the Wi-Fi signal.
- Weak router antenna: If the Wi-Fi router has small antennas or is placed in a poor location or orientation, the broadcast coverage area will be smaller.
Common Household Obstacles
Even in a typical household, there are many common items that can accidentally block you from getting the best Wi-Fi signal in certain areas. Some top obstructions found in homes include:
- Refrigerators and stoves
- Microwaves
- Aquariums
- Mirrors
- Filing cabinets
- Desktop computers
- Concrete walls or floors
Positioning the Wi-Fi router in a central, elevated location can help minimize obstructions between it and connected devices throughout the home. Avoid putting the router on the floor or in closets, surrounded by electronics and thick walls. Hardwired Ethernet connections can also bypass interference by delivering wired internet to devices. Extenders and mesh networks can also improve Wi-Fi coverage by creating a larger network of access points.
Materials that Block Wi-Fi Signals
Wi-Fi signals have varying ability to pass through different building materials. Dense, thick materials will severely attenuate and degrade Wi-Fi signals while thinner materials have less impact. Here is an overview of how well Wi-Fi can penetrate different materials:
Low Signal Penetration
- Concrete
- Brick
- Stone
- Marble
- Mirrors
- Bulletproof glass
- Sheet metal
- Foil insulation
Medium Signal Penetration
- Stucco
- Drywall
- Plywood
- OSB (oriented strand board)
- Glass
- Plastics
- Clear glass
High Signal Penetration
- Furniture
- Wood
- Plaster
- Synthetic materials
- Papers
- Fabrics
- Doors
As you can see, metal, concrete, and mirrors especially impede Wi-Fi signals. If these materials are between your router and connected device, you’ll likely experience a poorer connection. Consider placing the router and computers/phones on the same side of concrete walls when possible.
Sources of Electromagnetic Interference
Wi-Fi networks are susceptible to electromagnetic interference (EMI) from electronics and devices operating on the same radio frequency bands. Common sources of EMI include:
- Microwaves
- Cordless phones
- Wireless video cameras
- Garage door openers
- Outdoor lighting
- Wireless speakers
- Baby monitors
- Bluetooth devices
These devices can potentially transmit signals over 2.4GHz or 5GHz while in use, crowding and interfering with Wi-Fi data signals. Microwaves are one of the biggest interferers since they operate at 2.4GHz regardless if in use or not. Turning off or moving these electronics farther away from the router can help reduce EMI effects.
Other Factors that Impact Wi-Fi Signals
Beyond physical barriers and electromagnetic interference, there are some other factors that can influence Wi-Fi signal strength and coverage:
- Distance and area size – As the distance and coverage area grows, signal weakens. Large homes may need multiple access points.
- Bandwidth overload – Too many users/devices can crowd Wi-Fi channels and slow the network.
- Old Wi-Fi standards – 802.11b is limited to 11Mbps, 802.11g to 54Mbps. Newer 802.11n and ac allow much higher throughput.
- Obstructed antennas – Keep the router antennas straight and perpendicular to maximize directional coverage.
- Interference from networks – Neighboring Wi-Fi networks, especially on crowded channels, can interfere with your network.
- Physical router location – Elevated, central locations are best to spread coverage.
Adjusting factors like Wi-Fi router placement, removing congestion, and upgrading to newer networking equipment can often resolve these issues.
Tips for Improving Wi-Fi Signals
If your Wi-Fi network has dead zones or poor signals in parts of your home or office, there are some steps you can take to troubleshoot and improve wireless coverage:
- Move the router to a centralized location away from potential sources of interference.
- Adjust the router antenna orientation for best directional coverage.
- Upgrade routers or access points to newer standards like 802.11ac Wave 2 for performance gains.
- Use Ethernet cables to connect nearby stationary devices like desktop PCs or smart TVs.
- Set devices like cordless phones to avoid Wi-Fi channels in use.
- Upgrade modems and internet plans for more bandwidth to reduce congestion.
- Install Wi-Fi extenders or a mesh network system to expand coverage.
- Replace any old coaxial cable in the home with new RG6 or RG11 coax.
Running a Wi-Fi analyzer can also help you identify congested wireless channels and sources of interference in your environment. With some strategic adjustments and upgrades, you can extend strong Wi-Fi coverage to every corner of your home or office.
Conclusion
Reliable Wi-Fi connectivity is vital in homes and offices, but sometimes the wireless signals encounter obstacles. Concrete and metal barriers, distance, interference from electronics, and other factors can all block or degrade Wi-Fi networks. Identifying these obstructions and sources of interference is the first step toward troubleshooting and enhancing your wireless coverage. With a good understanding of what affects Wi-Fi signal strength, you can optimize the network for the best possible speeds and connectivity anywhere.