How to plan WiFi in a multi-storey home?

The floor slab is often a bigger problem than the walls

A reinforced-concrete slab between the ground floor and the upper floor attenuates the WiFi signal about as much as a load-bearing wall — sometimes more, depending on the reinforcement and thickness. If the router sits on the ground floor and the bedroom upstairs is also offset to one side, the signal has to cross both the slab and horizontal distance at once — the most common cause of “WiFi that barely works upstairs.”

Where to put the router in a multi-storey home

A good starting point is a spot as central as possible both horizontally and vertically — for example near the staircase on the ground floor, so the signal has the shortest path both to rooms on the same floor and up through the slab to the floor above. Placing the router in the basement or garage, even if that's where the provider's connection happens to end, usually means the weakest possible coverage on the upper floors.

When one router isn't enough for a multi-storey home

In a home with more than two usable floors (e.g. basement, ground floor, upper floor, attic), a single router often leaves dead zones on the outer floors. This is a case where mesh, with a separate node on each floor, works noticeably better than searching for one perfect spot for the whole house.

Garage, basement, and laundry room — typical dead zones

These rooms often have thicker walls (sometimes for structural or insulation reasons) and sit further away from the rest of the house. If you need WiFi in the garage or laundry room — say, to control a gate or IoT devices — it's worth marking it as a separate point at the planning stage, rather than hoping it “somehow catches a signal.”

Multi-storey planning, step by step

A sensible order is: plan each floor separately on the plan, mark the spots that matter most to you on each one, then check whether a single router is enough or whether you'll need an extra node with a good backhaul link.

Perfect WiFi supports multiple floors within a single project — you add a plan for each floor, and the app calculates the recommendation accounting for slab attenuation between them, instead of planning each floor separately and by eye.