One of the Parts of the building regulations limited flood light size without planning permission, however when I hunted for it, I couldn't find it, so maybe it has been dropped, but I think unlikely, I did find guides to regulations which seem to say 2000 lumen is the limit. But of course one can apply for permission so there is no limit of what can be bought, and back in the 90's I was fitting 500W and 1500W floods as if not tomorrow, then the 500W tube seemed to vanish and dropped to 300W then the mini flood arrived at 150W which I assumed to to comply with the new building regulations?
So I bought a quartz tube flood and replaced the tube with LED, seem to remember around 8W which was plenty to light dark areas of our small drive, seem to remember in mothers house used a 10W again LED but built into light, longer drive and still ample, around twice length of house, however it did not have the controls on the PIR in the same way and ended up with tape over part of the PIR to reduce how sensitive.
The same problem in this house, having a carriage lamp light up when cat passes is OK, likely a 10W bulb non directional, however having a 20W flood lights come on with a PIR it is rather bright and you don't want it lighting when wind moves a tree or cat walks by, not sure why a tree should trigger a PIR but in high winds it does. Must be some thing hot beyond it.
The lights do have switches at the door to turn them off, but the switches will not turn them on unless the PIR is activated, nothing as annoying as walking from car with an arm full of stuff walking up the steps and the light goes off, so I have on my to do list replace PIR with a wifi unit so I can select when it lights using my phone. Likely use simple plug and socket with wifi socket, it is also good for isolation should water get in lamp.
