What is the recommended overlap percentage between adjacent AP cells in a data WLAN design?

5% overlap is insufficient and creates coverage gaps at cell edges, causing clients to drop association before successfully roaming to the next AP.

Cisco and industry WLAN design guidelines recommend 10%-15% cell overlap for data WLANs to provide enough signal continuity for client roaming while avoiding excessive co-channel interference caused by too much overlap. This overlap ensures that a client nearing the edge of one AP's cell still has sufficient signal from an adjacent AP to roam before losing connectivity, maintaining session stability without degrading network performance.

20%-30% overlap is the recommended range for voice WLANs, which require tighter coverage continuity for real-time traffic, and is excessive for standard data designs.

50% overlap causes severe co-channel interference between APs and wastes RF resources, significantly degrading throughput for all clients in the overlapping area.