Guide - How many Access Points should be installed in a home?

Peppino

Designing reliable home Wi-Fi is no longer as simple as placing a single router in the middle of the house and hoping for the best. Modern homes—filled with mesh devices, IoT sensors, smartphones, streaming, and videoconferencing—demand a structured and predictable wireless design. The goal is always the same: deliver strong, consistent, and interference-free Wi-Fi.

But how many APs does a home really need?
Why is one usually not enough—and why can too many actually make things worse?

This article provides practical guidance, real-world examples, and professional deployment tips based on years of field experience and countless site surveys.

Why a single AP is often not enough

In a typical European home—especially a multi-floor house with concrete walls—a single AP will struggle for several reasons:

Wi-Fi is a two-way conversation

Even if the AP transmits at high power, your client devices (smartphones, tablets, IoT) do not.
A phone or a laptop transmits at a fraction of the AP’s power.
This results in the classic phenomenon:

The client “hears” the AP, but the AP does not “hear” the client. 

This leads to dropped packets, reduced throughput, sticky clients unable to roam and surprisingly poor performance far before “signal bars” drop to zero

Floors and walls are the enemy

Concrete slabs and brick walls attenuate signal heavily, especially on 5 GHz and even more on 6 GHz.
If the AP is on the ground floor, the second floor may receive only marginal coverage, causing low MCS rates and constant retransmissions. Even a single-pane glass could drop the signal with as much as 50%. Here is a representation of some typical attenuations:

How to read % loss

• –3 dB ≈ 50% power loss
• –6 dB ≈ 75% power loss
• –10 dB ≈ 90% power loss
• –20 dB ≈ 99% power loss
• –30 dB ≈ 99.9% power loss

Glass Type	2.4 GHz Loss	5 GHz Loss	Effect Summary

Standard single-pane glass	–1 to –3 dB → 20–50% loss	–3 to –4 dB → 50–60% loss	Very small effect; normal window.

Double-pane / insulated glass	–2 to –4 dB → 35–60% loss	–4 to –6 dB → 60–75% loss	Still acceptable; better than a wall.

Low-E coated glass (metallic coating)	–10 to –15 dB → 90–97% loss	–15 to –25 dB → 97–99.7% loss	Nearly blocks Wi-Fi; behaves like metal.

Metallic-tinted or IR/UV reflective film glass	–15 to –30 dB → 97–99.9% loss	–15 to –30 dB → 97–99.9% loss	Practically a Faraday cage; extremely high attenuation.

The home’s layout isn’t Wi-Fi-friendly

Rooms, corners, kitchen appliances, even under-floor heating can create dead zones.
One AP simply cannot overcome these physical barriers.

Why too many APs is not only wasteful—it is harmful

Many users assume that “more APs = better Wi-Fi.” Unfortunately, the opposite is often true.

Wi-Fi is like a big, very crowded room

Imagine a room full of people. If everyone speaks loudly at the same time, nobody can understand anyone, even if they stand next to each other. 

Access points and clients share a common medium, and only one can talk at a time.

When you install too many APs, three problems immediately appear.

APs begin interfering with each other. Whether 2.4 GHz, 5 GHz, or 6 GHz, radios must share the air. Extra APs create co-channel interference (same channel overlaps), adjacent channel interference (wide channels overlapping), constant backoff and collision avoidance and poor roaming because clients see “too many” AP candidates

The result will be capacity decreases instead of increasing, beacon overhead increases dramatically. Each SSID must transmit beacons. More APs × more SSIDs = less airtime for real traffic.

For example 3 APs × 4 SSIDs = 12 sets of beacons blasting every 100 ms. This can easily consume 10–25% of usable airtime.

When APs are too close and at high power, coverage cells overlap excessively.
Clients stick to far APs, roam too late, experience unstable MCS rates or suffer unnecessary retransmissions. Proper Wi-Fi requires balanced AP power and spaced-out cells, not brute-force saturation.

Channel width, frequency choices & real-world problems

2.4 GHz

• Use only 20 MHz channels
• Use a maximum of ONE SSID if possible
• Avoid multiple APs on this band unless required for IoT

5 GHz

• Use 20 or 40 MHz in dense environments
• Avoid 80 MHz unless you are in a low-interference suburban home
• DFS channels are usually beneficial but may be problematic in airport-dense areas

Apartments: the worst-case scenario

In most European apartment buildings, there are: dozens of neighboring APs, extremely loud 2.4 GHz environment, 5 GHz is only partially usable and 6 GHz is often the savior (if supported by clients)

Even if your voice is loud, in a crowded room with 50 people shouting, you can barely hear anything.

In such apartments 2.4 GHz is mostly unusable, 5 GHz must use 20 MHz channels, high-power operation makes things worse and multiple APs may not help at all if channels cannot be isolated

Absolute best practices for apartments:

• Use the minimum number of APs (often only 1 or 2)
• Turn down transmit power
• Use 20 MHz or 40 MHz channels
• Prefer 6 GHz whenever possible
• Disable unused SSIDs
• Do NOT use “maximum power” unless you absolutely know you need it

So how many APs do you actually need?

Small apartment (40–70 m²):

• 1 AP is enough (preferably ceiling-mounted, central location)

Medium apartment (70–120 m²):

• 1 AP, maybe 2 APs if walls are thick or layout is L-shaped

Two-story home (120–200 m²):

• 2 APs, one per floor
• Low transmit power
• 5 GHz or 6 GHz-focused design

Large house (200+ m², multiple floors):

• 2–3 APs depending on internal layout
• Avoid more unless rooms are isolated or SSIDs differ per floor

Smart home with many IoT devices:

• Use one dedicated IoT SSID, low bandwidth
• Use 2.4 GHz sparingly
• Keep IoT on the AP closest to the devices

Professional deployment tips for Zyxel AX Series APs

Always mount on the ceiling for best propagation. Keep AP count low unless you can separate channels cleanly. Lower transmit power instead of raising it.

Use:

1. 20 MHz channels in dense apartments
2. 40 MHz in low-density homes
3. 80 MHz only in larger homes with minimal neighbors

Avoid more than 2–3 SSIDs on any AP.

Place APs:

1. away from corners
2. away from TVs or metal cabinets
3. centrally on each floor

For multi-AP homes:

1. Ensure non-overlapping channels
2. Keep 5 GHz power medium/low
3. Allow clients to roam properly