Twenty-five people walk into the large meeting room for a quarterly review. Every laptop shows full Wi-Fi bars, yet the video call freezes, the shared presentation will not load and someone starts tethering to their phone. The signal is fine. The network was simply never designed for twenty-five people in one room at the same time.
This is the most common Wi-Fi misunderstanding in offices: designing for coverage — a signal everywhere — instead of capacity — enough airtime for everyone, where they actually sit and meet.
Coverage answers 'can I connect?'; capacity answers 'can we all work?'
A Wi-Fi channel is a shared medium: only one device can transmit on it at a time, and all devices connected to an access point share its airtime. A device with a weak signal or an older Wi-Fi standard transmits slowly and uses more airtime for the same amount of data, slowing everyone else down.
So one powerful access point in the middle of the floor may cover the whole office and still fail at ten in the morning, when fifty laptops, fifty phones and several video calls compete for the same channel. Capacity comes from the number of channels in use at the same time — in other words, from more access points, well placed, on different channels.
Start from people, devices and applications
Before anyone talks about access point models, describe how the space is used:
- How many people sit or meet in each zone at peak — not on average.
- How many devices per person: usually a laptop and a phone, sometimes more.
- Which applications matter: video calls, cloud applications, large file transfers, voice over Wi-Fi.
- High-density areas: meeting rooms, training rooms, canteens, reception.
- Special devices: scanners, label printers, IoT sensors that may support only 2.4 GHz.
- Construction: concrete walls, glass partitions, elevator shafts, metal shelving.
Choose bands and channels deliberately
- 2.4 GHz: longer range, but only three non-overlapping 20 MHz channels in most regions and plenty of interference. Keep it for legacy and IoT devices, not as the main band.
- 5 GHz: many more channels — the workhorse of office Wi-Fi.
- 6 GHz (Wi-Fi 6E and Wi-Fi 7): plenty of clean spectrum but shorter range; useful where devices support it and local regulations permit its use.
Wider channels promise higher peak speeds, but they reduce the number of channels you can reuse across the floor. In dense offices, 20 or 40 MHz channels on 5 GHz often deliver better overall performance than 80 MHz or wider, because neighboring access points interfere with each other less.
More access points at lower power
The intuitive fix — turning up the transmit power — usually makes things worse. At high power each access point's signal spreads over a larger area, more access points interfere with each other on the same channel, and devices cling to a distant access point instead of roaming to a nearer one. A better design uses more access points at moderate power, mounted on or near the ceiling in the rooms where people actually are — not in corridors.
The wired side: cabling, PoE and switches
Every access point needs a cable. Copper Ethernet runs are limited to a 90 m permanent link (100 m channel), access points are usually powered over PoE, and the switches feeding them need enough PoE budget and uplink capacity. Newer access points may benefit from multi-gigabit ports. Planning access point positions together with the structured cabling and switching avoids the classic compromise of putting an access point where a cable happens to be, rather than where the users are.
Survey, install, then validate
- Predictive design based on floor plans, construction materials and the capacity requirements above.
- On-site check of critical areas, especially where materials are unknown.
- Installation and configuration: channels, power levels, a small number of SSIDs, roaming settings.
- Post-installation validation survey: signal, interference and channel overlap measured on site.
- Load test in high-density rooms — for example, a real meeting with video calls.
- Documentation: access point locations, channels and settings as installed.
Keep the number of SSIDs low — each one adds overhead on every channel — and separate the guest network from the internal one. Spaces such as classrooms or hotel conference halls follow the same logic, only at even higher density.
Questions to ask a Wi-Fi contractor
- What capacity assumptions — people, devices, applications — is the design based on?
- Which bands and channel widths do you plan to use, and why?
- How will you validate coverage and capacity after installation?
- How are the guest and internal networks separated?
- What documentation will we receive?
Wi-Fi that looks fine on paper but struggles in practice? Tell us where it hurts — we can help assess the current design and plan improvements.