Wi-Fi in the garden: how to get signal outside

Wi-Fi in the garden seems like it should be the easy case. Outside there are no walls, no furniture, no fridges. And yet the connection often dies a step past the back door. The problem isn't the garden: it's getting the signal out of the house.

Why the signal stops at the door

Outer walls are the heaviest in the house. They're thicker than interior walls and often brick, stone or concrete with insulation. In NIST's laboratory measurements, brick cost about 6 dB at 2.4 GHz and 15 dB at 5 GHz, and concrete much more.

Windows can be worse than walls. Modern double and triple glazing often has a low-emissivity coating, a thin metallic layer that keeps heat in. It reflects Wi-Fi in the same way. An open door or an old single-glazed window lets the signal through; a new insulated window may not.

The router is usually on the other side. The line comes in at the front of the house, the garden is at the back, and the signal crosses the whole building before it even reaches the outer wall.

Distance outside adds up fast. Once it's out, the signal fades with every metre, and devices outdoors, a phone, a speaker, a camera, have small antennas.

Decide what you actually need

Covering the whole garden is rarely necessary. Most people need two or three places: the terrace table, a bench, a hammock, a garden office or shed at the end. Walk to each one with your phone and take a reading. On an iPhone, AirPort Utility's Wi-Fi scanner shows the signal in dBm; see how to check Wi-Fi signal strength on iPhone.

Then take the same reading just inside each window and door on the garden side. The one where the signal is strongest is where the signal leaves the house most easily, and where anything you add should go.

Covering a terrace or a patio

If the spots you need are close to the house, the simplest fix is a mesh node inside, by the garden-side door or window where the signal leaves best. It has to receive the router well where it stands, just like any node; where to put a mesh node explains how to find the spot.

On 2.4 GHz, the signal carries further outdoors than on 5 GHz, so a phone or speaker at the far end of the terrace may be steadier on 2.4 GHz.

Don't put an indoor node or extender outside. Rain, condensation, frost and direct sun will damage it.

Covering the garden properly

For a large garden, or spots far from the house, an outdoor access point is the reliable answer. These are built for the weather, with a rating such as IP65 or higher, and are usually powered and connected through a single Ethernet cable, using a technique called Power over Ethernet. Mount it high on the outside wall facing the garden, or under the eaves, and run the cable through the wall to the router or to a switch.

Many mesh systems sell an outdoor unit that joins the same network, so phones move between inside and outside without changing networks.

A garden office or a shed

A room at the end of the garden is a small building of its own, often with its own walls and windows between you and the signal. Three ways to connect it:

A cable. Outdoor-rated Ethernet in a buried conduit gives the office a proper connection, with an access point inside. If you're building or renovating the office, this is the time to lay it.

A point-to-point wireless bridge. Two small outdoor antennas, one on the house and one on the office, pointed at each other, carry the network across the garden. They need a clear line of sight but work over long distances.

Powerline, if the office is on the same electrical supply as the house. It's quick to try; results vary with the wiring and distance, so buy it where you can return it.