UK smart home planning: B22 or E27 lights and other considerations

I am planning a major UK house renovation including a rewire.
I want to have this as futureproof as possible including for a smart home.

Would you fit the B22 light fittings common in UK homes or have E27 fittings in line with much of the rest of the world?

Most if not all bulbs will be smart, locally controlled using Home Assistant. I’m currently using Zigbee and hope Matter over Thread will be feasible soon.

What other things would you do to make a house smart home ready if you could start from scratch?

I’d not fit any “stupid bulbs” as they are at best a stop-gap workaround to a problem that simply should not exist in a new property.


  • Fit triple-and-cpc to the switch-plate and use 35mm back boxes to allow easy installation of any variety of controllable light switch (with local dumb control in case HASS fails)
    This is likely to be understandable to a “normal” elec eng.
  • Wire lighting with “home runs” back to a central sub-main DB fitted with DIN-rail mounted controllable light switch
    More cable needed, but very future proof

The type of ceiling rose / fitting is a decoration issue, not a technology one.

Just remember - if you have to do something, it’s not “smart”. In my home, pressing a light switch or app is an issue that needs to be fixed!

My traditional wired retrofit home uses controllable light modules behind the ceiling rose (with secondary insulation as per BS7671) only as this is a convenient way to pick up phase, neutral, switch, and load in one location.

For different thoughts on UK automation infra, try:



Oh, and MK (and Ashley)make 4-conductor plugable ceiling rose fittings, so the pendant type is irrelevant - just unplug it with a twist.

I would use dumb “dim2warm” bulbs rather than smart bulbs where I could and use in-wall dimmers to control them.

Thanks both, interesting thoughts.

I certainly want to use faceplates or backbox modules so anyone can walk in, press a light switch, and get the expected result.

I hadn’t considered using a different wiring solution to standard, I suppose I’d thought that wireless protocols would make KNX etc redundant, but I will look into this further

If you’re after some architectural thoughts on wireless protocols, this thought piece might be of interest:

Wired systems are still relevant, however the install costs and generally higher prices mean they are more pro than consumer. The general difference is distributed control sensor direct to actuator, rather than sensor → hub → actuator. The direct approach is more often used in large commercial Building Management Systems where one hub would collapse under the load (think a tower block like the Shard).

Some only sell to accredited pro installers, but KNX is still out there. If I were self-building, I’d definitely look at installing data cabling like Mat Smith “just in case” but suspect flexible plastic duct might be better long-term than Cat5e/Cat6 for at least main service areas.

The Cat5e in the walls will last my lifetime, but runs like from the telecoms demarcation point (e.g. Openreach NTE) would be better as duct. Openreach is already not installing copper to homes, the analogue PSTN is off in 2025, and full fibre everywhere (except remote hill farms) might happen before 2035.

I’ve already pulled out CT100 coax for Cat5e behind dry-lining dot-and-dab - easy with ducting; still possible with careful plasterers and lots of 1st fix photos.

Simple is also still useful - a dumb £25 ceiling PIR switch can still work well, and LED fittings with microwave motion sensors are also pretty good for corridors (£35ish, £60 with emergency light battery back up). Dumb is great for fire escape routes!

Thanks James, the video was a great watch