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Most dimmers in older homes are leading edge , designed for filament lamps. LEDs generally need a trailing edge dimmer, and the dimmer's minimum load has to be met — five 5W LEDs may total less than the dimmer needs to work.
9 questions in this topic. General UK guidance, not advice about a specific property.
Most dimmers in older homes are leading edge, designed for filament lamps. LEDs generally need a trailing edge dimmer, and the dimmer's minimum load has to be met — five 5W LEDs may total less than the dimmer needs to work.
Check the lamps are marked dimmable, then match the dimmer to them. Mixing brands of LED on one circuit also causes uneven dimming.
Usually yes, provided the dimmer suits the lamps and the load, and that two-way switching is handled correctly — a two-way circuit normally needs a matching dimmer at one end and a special switch at the other.
It is non-notifiable work outside a bathroom, but it should still be tested and certified, and the switch should not be worked on live.
Two-way switching lets one light be controlled from two points — the classic stairs and landing arrangement. Adding a third or fourth point uses an intermediate switch between the two.
It needs the right cabling between the switch positions, so adding a second switch point to an existing single switch normally means running new cable, not just changing the plate.
Three practical points: they should be fire rated where they cut through a fire-resisting ceiling, they need clearance from loft insulation unless designed to be covered, and they must not be positioned where joists or pipework run.
Fixed integrated LED units are now more common than replaceable-lamp fittings — worth knowing, because when the LED fails the whole unit is replaced.
There is no fixed rule, and more is not better — evenly spaced ceiling lights produce flat, unflattering light. Good design usually mixes a general layer with task lighting over worktops and desks, and accent lighting for atmosphere.
Tell us the room size, ceiling height, what happens in the room and whether you want it dimmable, and the layout can be planned around that rather than a grid.
Usually yes, by extending the existing lighting circuit. The practical questions are the cable route — whether a ceiling can be accessed from a loft or has to be chased — and the condition of the existing circuit, which should be tested before more is added to it.
An addition to an existing circuit is an alteration, so a Minor Works Certificate should be issued for it.
The key question is whether you want smart lamps (simple, no wiring change, but the wall switch must stay on) or smart switches (better for how people actually use rooms). Many smart switches need a neutral conductor at the switch, which older lighting wiring often does not have.
Deciding this before first fix on a renovation saves a lot of trouble — running the extra conductor later means opening walls.
Bathroom fittings are chosen by zone and IP rating. Inside a bath or shower (Zone 0) only low-voltage SELV fittings rated IPX7 are permitted; directly above and around it (Zone 1) needs at least IPX4; the area adjacent (Zone 2) also needs at least IPX4.
All of it requires RCD protection, and work in a bathroom is notifiable under Part P in England.
Yes — PIR sensors, photocells and timers are all straightforward to incorporate, indoors or outdoors. The usual pitfalls are siting a sensor where it triggers on passing traffic, and pairing a sensor with LEDs it cannot switch reliably.
Outdoor sensor lighting should be weather-rated and RCD protected, and aimed to avoid nuisance to neighbours.