It’s tempting to work out access points from floor area: so many square feet per access point, round up, done. The result is often an office with strong signal and poor performance, because coverage is only half of wireless design. The other half is capacity.
Coverage versus capacity
Coverage is whether a device can hear the network at a usable signal level everywhere it’s needed. It’s shaped by distance and by what the signal passes through — drywall costs little, but concrete block, brick, glass with metallic coatings, elevators and metal shelving can cost a lot.
Capacity is how many devices, doing how much, each access point has to serve. A conference room with twenty people on a video call needs far more capacity than a hallway, even though both need coverage. Every phone, laptop, tablet, VoIP handset, printer and scanner shares the airtime of the access point it’s connected to.
An office designed only for coverage typically works in the morning and slows down when everyone is in.
Why more access points can make it worse
Access points near each other on the same channel compete for airtime. Adding units without planning channels and transmit power can increase interference, especially on the crowded 2.4 GHz band. Well-designed networks use enough access points, placed deliberately, at sensible power levels, with channels planned so neighbours don’t interfere.
What actually determines the number
- Floor plan and building materials
- Number of people and devices in each area, and what they’re doing
- Applications: video calls and voice need consistent performance; email is forgiving
- Client devices: older devices and IoT equipment can slow the network for everyone
- Interference from neighbouring networks in shared buildings
- Outdoor or warehouse areas with high ceilings and racking
Is mesh good enough for a business?
Consumer mesh systems that relay traffic wirelessly between units lose throughput at every hop and offer limited management and segmentation. For most businesses, access points cabled back to a managed PoE switch, with centrally managed settings, deliver more consistent performance and allow business, guest and device traffic to be separated securely. Wireless backhaul still has a place where cabling is impractical.
When is a site survey worth it?
- Any multi-room office, clinic or warehouse
- Buildings with concrete, block or metal construction
- Spaces with high device density such as training rooms
- When VoIP over Wi-Fi or wireless scanners must roam without dropping
- Before replacing a network that already underperforms
A survey measures signal and interference in the actual building so access-point placement is based on data. After installation, a validation survey confirms the design goals were met.
Struggling with dead zones or slow Wi-Fi? Ask us about a wireless assessment.