Some Principles for Home Automation

This complete apartment rennovation isn’t my first foray into home automation - I’ve had my rental place automated for years, and it’s given me a lot of insights into how things work in the real world.

I’m using a mishmash of Wifi, Zigbee and ESPhome gadgets. This is undestandable - landlords hate you smashing open walls to rewire things - but these wireless technologies are kinda rubbish. I seem to be changing batteries on Zigbee devices evey day, and until I complete that task, the device in question is offline. Devices in hard-to-reach areas just don’t get dealt with. Quite often the wireless spectrum in our heighbourhood gets flooded by random data ¹ and both Wifi and Zigbee networks drop out for minutes at a time. My laptop is liable to lose wifi signal if I sit at the wrong part of my desk.

And then there’s relying too much on Home Assistant itself. The software itself is hella robust. But by nature of it being a software application it is liable to go down. And when HA goes down, so does the ability to control our home, because I have it too centralised. One morning this winter we woke up to the apartment at 12C, because I’d messed up an automation and the heating relied on it to operate.

So there’s the chance to plan things better in the new place by coming up with a few guiding principles.

Principles

I’ve had these principles growing in my head ever since I started embaressing myself with home automation. They can be boiled down to:

• Start Simple, End Smart
• Use Independent Systems
• Make the Important Things Resiliant
• Open Standards, Open Formats
• Use Local Communication

I see them as guiding principles, and not absolute laws. Your milage may vary of course, and you may see these as daft overcomplications. No worries if so.

Principle 1: Start Simple, End Smart

I’ve fallen fowl of going too smart, too quickly. My worst crime was installing smart light bulbs in the ceiling and then having to tape the light switches so that no one turns them off manually. To be clear, this is absolutely unacceptable. This should never happen if you’ve planned things well.

The average home should always start off in a basic mode, with no smart features. Light switches turn on lights directly. Front doors open with keys. Devices are operated manually. ²

Perhaps I’m a paranoid, but I don’t think I trust technology. Wait, no, scratch that. I KNOW I don’t trust technology - it’s not paranoia if you know you’re right.

Technology fails. Systems go offline. Freak power surges happen. Trade wars make everything so expensive that you might not be able to afford luxury home automation kit.

No, it’s only when the basics are in place should an interface be upgraded with smart abilities. Normal light switches can be replaced with Zigbee light switches that work even when the network is down. The front door lock can be replaced with a smart lock that still has a key (or the house retains an additional “normal” door that can be accessed). A lamp can have a its switch replaced with a smart relay that works as a button and via the Zigbee network. A water pipe can have an additional smart valve installed downline, while retaining the original manual valve.

Interface devices must be able to revert back to their basic operational states in the event of system problems.

Principle 2: Use Independent Systems

As few systems as possible to be directly run by Home Assistant - it should have the role of orchestrating independent systems, not running them.

Heating, for example, should be an independant system with its regulation. HA should only be in the position of listening to the data it emits, and requesting that it changes its temperature.

Your home systems should work without relying on other systems.

Principle 3: Make the Important Things Resiliant

Some aspects of home automation will always be frivilous. Changing lighting scenes easily is a lovely feature to have, but no one is going to suffer if it doesn’t work. But other aspects will be absolutely critical - if I can’t turn on the lights on at all when there’s a fire, then that’s a threat to the life of my loved ones.

This means that there is a scale, with critical automation systems being robust, while the silly ones being ephemeral.

• Critical - Failure can impact health or finances.
• Daily - So integrated into your life they’re noticed only when gone.
• Fancy - For aesthetic purposes. Not needed, so much as wanted.

The hardiness of a system must be proportional to its importance.

Principle 4: Open Formats, Open Standards

I almost omitted this as it’s so deeply embedded in my philospohy! If your home is using closed formats, closed standards, or closed APIs, it’s at risk. Don’t rely on proprietary APIs. Don’t use systems that can’t be repaired.

Closed systems are anethema to a viable automated home.

Principle 5: Use Local Communication

At no point should you be relying on any daily or critical systems that are remotely based. It’s out of your control, and if it’s from a commercial entity then they will pull the plug at some point. Any system that you integrate into your home should be locally accessible. That doesn’t mean “don’t use commercial products”. No, it means make sure that you’re not relying on a remote endpoint that can (and will) be shut down at some point. You could be using this stuff for decades to come, but I doubt any company is interested in supporting their products for that same length of time.

In Practise

Thinking about these principles made me consider my upcoming automation work in a new light. I’m going to need several different systems, all working independently, yet together, built with the most simple implementation first.

• Security.
• Climate (heating).
• Air Quality.
• Fire, smoke, and heat detection.
• Electricity monitoring.
• Water monitoring.
• Internal blinds.
• External shutters.
• Audio Visual equipment.
• Lighting.
• Cleaning.
• Door locks.

I’ll take a look at these various systems as this whole thing progresses.