Bathroom Lighting Design Guide

UK wiring regulations divide bathrooms into zones based on how close a fitting is to water, and each zone has a minimum IP (Ingress Protection) rating that any electrical fitting in that zone must meet. Zone 0 is inside the bath or shower tray itself, requiring the highest protection, typically IP67 or IP68, and generally only low voltage fittings are used here. Zone 1 is the area directly above the bath or shower up to 2.25 metres, needing at least IP44 rated fittings. Zone 2 extends 0.6 metres beyond the bath or shower and around basins, needing IP44 as well in most cases.

Outside these zones, in what's sometimes called zone 3 or the general room area, standard fittings can often be used, though we'd still generally recommend a reasonable level of moisture protection anywhere in a bathroom given how much steam an average shower generates. It's a genuinely common mistake to fit a nice-looking pendant light or a non-rated fitting too close to a bath or shower, which isn't just against the regulations, it's a real safety risk.

We check zone compliance as standard on every bathroom lighting job, and we're always happy to explain why a particular fitting can or can't go in a specific spot in your room, since it's not always obvious to look at a fitting whether it's genuinely rated for a bathroom or just styled to look like it.

A single central ceiling light, however bright, tends to leave a bathroom feeling flat and leaves shadows in the corners and around the mirror, which is exactly where you need good light for shaving, applying makeup or checking your appearance before leaving the house. Layered lighting solves this by combining a few different light sources rather than relying on one.

A sensible layered approach usually includes general ceiling lighting (either a central fitting or a spread of recessed downlights) for overall illumination, dedicated lighting at the mirror or vanity area for tasks that need good, even light on the face, and sometimes a lower-level accent light, such as a strip light under a vanity unit or in a recessed niche, which adds a softer ambient glow, particularly useful for a bathroom used at night without needing the full brightness of the main lights.

This layered approach doesn't need to be expensive or complicated. Even a modest bathroom benefits from separating the mirror light from the general ceiling light onto its own switch, so you're not always forced to choose between full brightness or nothing.

Mirror lighting deserves particular attention because it's the light you'll actually use most for practical daily tasks. Light positioned above the mirror alone can cast shadows downward across the face, which isn't ideal for shaving or makeup application. Light positioned to the sides of the mirror, at roughly face height, gives more even, flattering illumination, similar to the lighting used around dressing room mirrors.

Illuminated mirrors and mirror cabinets with built-in LED lighting have become popular precisely because they solve this problem neatly, providing edge-lit or backlit illumination around the mirror itself without needing separate wall lights either side. Many also include a demister pad, which keeps the mirror clear of condensation, a genuinely useful practical feature in a small, steamy room.

Colour temperature at the mirror matters more than in general room lighting too, since it affects how accurately you can judge your own appearance before leaving the house. We'd generally recommend a neutral white light here rather than a very warm or very cool tone, for reasons covered in more detail below.

Light bulbs and LED fittings are rated in Kelvin, and this rating has a real effect on how a bathroom feels and how accurately colours and skin tones are represented. Warm white, around 2700 to 3000 Kelvin, gives a cosy, relaxing feel similar to traditional filament bulbs, which suits a bathroom used mainly for relaxing baths in the evening. Cool white or daylight, around 4000 to 5000 Kelvin, gives a crisper, brighter feel closer to natural daylight, which suits practical tasks like shaving or makeup application at the mirror.

Many bathrooms benefit from mixing these slightly, a warmer general room light for ambience alongside a cooler, more neutral light at the mirror specifically for accurate task lighting, though this obviously depends on personal preference and there's no strictly right answer here.

What we'd generally caution against is a very cool, clinical light temperature throughout the whole room, which can make a bathroom feel a bit sterile and unwelcoming, particularly in a family bathroom used for relaxing baths as well as quick practical use.

Recessed downlights set into the ceiling give a clean, unobtrusive look and work well for general room illumination, particularly in bathrooms with a reasonably flat, solid ceiling suitable for cutting the necessary holes. Fire-rated downlights are generally required in most UK homes, and IP-rated versions are needed within the relevant bathroom zones as covered above.

Surface-mounted fittings, wall lights, pendant fittings outside the wet zones, and surface ceiling fittings, suit period properties or ceilings that aren't suitable for recessing, such as ceilings with limited void space above them, or where preserving an original ceiling matters more than achieving a fully flush look.

Neither approach is inherently better, it depends on the room, the ceiling construction and the overall style you're going for. In a lot of the period properties we work on across Gloucestershire, a mix works well, recessed downlights where the ceiling allows it, and a surface fitting or wall light where an original ceiling is being preserved.

Dimmable lighting adds real flexibility to a bathroom, allowing full brightness for practical tasks and a softer setting for relaxing baths in the evening, without needing separate fittings for each. Not every LED fitting is dimmable though, so this needs specifying at the point of choosing fittings rather than assumed afterwards, since retrofitting dimming to a non-dimmable fitting generally isn't possible.

Extractor fans are often wired into the same circuit as the main light switch, so the fan runs automatically whenever the light is on, with an overrun timer keeping it running for a set period after the light is switched off to continue clearing moisture from the room. This is a sensible, low-maintenance approach for most households, though a separate switch or a humidity-sensing fan gives more control if preferred.

All of this electrical work in a bathroom needs to comply with Part P of the building regulations, and certain bathroom electrical work needs to be certified by a suitably qualified person. We handle this properly as part of any bathroom installation, so you're not left with lighting or an extractor fan that technically shouldn't have been fitted the way it was.

Lighting is easy to leave as an afterthought in a bathroom project, but it's genuinely worth thinking through at the same stage as the tiling and fittings, since ceiling access, zone positioning and switch locations all need to be planned before walls and ceilings are closed up. Retrofitting better lighting after a bathroom is finished is far more disruptive and expensive than getting it right the first time.

We handle the plumbing, tiling, fitting and electrical work for bathroom projects in house, which means lighting is planned as part of the whole room design rather than bolted on at the end, and it's properly certified as part of the finished job.

If you're planning a new bathroom or thinking about upgrading the lighting in an existing one anywhere across Gloucester, Cheltenham, Tewkesbury, Stroud, Newent or the Forest of Dean, we're happy to visit, talk through the options and provide a free written quote. Call 07927 593 585 or get in touch through /contact.