Home Assistant: devices, automations and local control

Home Assistant connects smart home devices and lets you coordinate them through a shared set of controls and automations. It is useful when your lights, heating, sensors and cameras come from different manufacturers and their separate apps do not work well together.

Its main attractions are support for many devices, configurable automations and the option to keep more control on your own network. The result depends on the equipment and integrations you choose. Some still need a vendor's account or cloud service.

Dashboards bring selected controls and information into one place.

Connecting devices

Home Assistant is open source, and integrations connect it to devices and services. At the original publication of this article, the project listed more than 2,800 integrations. Examples included Philips Hue, Lutron, Sonos, Ring, Apple HomeKit Bridge, Google Cast and Nest.

It also supports ways to connect equipment locally, including Zigbee, Bluetooth Low Energy, Matter, ESPHome and MQTT. Check the requirements of the device and integration you intend to use rather than assuming that support always means local operation.

Once connected, a device can expose entities such as a lamp's switch, a door sensor's state or a washing machine's power reading. Labels and areas help organise them. You might group lights by room or use an area such as the ground floor to select related devices.

Building automations

An automation responds to an event, checks any conditions and runs the actions you have chosen.

For example, you could:

• Adjust heating when a room becomes cold and someone is home.
• Use soil moisture readings to decide when garden irrigation runs.
• Send a notification when an appliance's power use changes.
• Change lighting or camera settings when the household leaves.

The important part is defining the behaviour you want, including the exceptions. A heating schedule may be useful on weekdays and wrong at the weekend. A presence sensor may need a delay so lights do not turn off when someone briefly stops moving.

These terms appear throughout Home Assistant:

• A trigger starts an automation, such as sunset or a sensor changing state.
• A condition is a check that must pass before an action runs, such as someone being at home.
• An action does the work, such as turning on a light or sending a notification.
• A script holds a sequence of actions that can be reused.
• A scene describes a set of device states, such as downstairs lights at a chosen brightness.

Our first automation walkthrough uses a finished 3D print to trigger a watch notification, then turns off an extractor fan after a delay.

Selected controls and notifications can also be available on a watch.

Local control and privacy

Local control can reduce the need to send device data through a remote service. It can also reduce dependence on a provider keeping an app, account or subscription available.

This matters particularly for cameras and other devices that reveal what happens inside a home. Reported incidents involving connected devices include:

• The FTC's action concerning Ring employees and camera access.
• A reported vulnerability in Belkin Wemo smart plugs.
• Anker's acknowledgement about Eufy camera encryption.

Home Assistant does not automatically remove every cloud connection. Some integrations require vendor authentication or remote services to function. Review each one and decide whether that dependency is acceptable.

A local installation also needs maintenance, backups and appropriate access controls. If you want remote access, consider how it will be authenticated. Moving control into the home gives you more responsibility for running it.

Start with one useful routine

Choose a task that repeatedly needs your attention. Connect the relevant devices, build a small automation and test it under the conditions in which it will run.

Keep a manual way to operate the equipment and decide what should happen when a device is unavailable. Once the first routine works reliably, you can add another without having to redesign the entire home at once.

Email us if you want help connecting devices or working through an automation that is not behaving as expected.