Bathroom Lighting Zones and IP Ratings Explained

Read this first: who does the wiring

This is an explainer, not an installation guide. Fixed wiring in a bathroom, including lights, must be designed, installed and tested by a qualified electrician. Nothing here tells you how to connect, move or replace mains wiring or fittings. Use it to understand the zones and ratings so that you can choose fittings, plan a scheme and ask the right questions.

In England, electrical work in dwellings is covered by Building Regulations Approved Document P. It says installations should be designed and installed in accordance with BS 7671, that notifiable work includes a new circuit, a consumer unit replacement and "any addition or alteration to existing circuits in a special location", and that a special location includes a room with a bath or shower.^[1] Because the document is dated 2013, check with your electrician or local building control for what applies today.^[2]

What the zones are

Bathrooms have electrical zones because water and electricity are a dangerous mix. The zones in the wiring standard BS 7671 (Section 701, "locations containing a bath or shower") are defined by SELECT, a trade body, in its pocket guide to BS 7671:2018+A2:2022 as follows.^[3]

• Zone 0: the inside of the bath tub or shower basin.
• Zone 1: the space above the bath or basin, up to 2.25 m from the floor or the highest fixed shower head, whichever is higher.
• Zone 2: the area beyond zone 1 for 0.6 m horizontally, up to 2.25 m high.
• Outside the zones: the rest of the room, where sockets (other than very low voltage ones) are not allowed within 2.5 m horizontally of the zone 1 boundary.^[3]

Screwfix and Downlights Direct describe the same layout in simpler terms, and Screwfix adds that "zone 3" is not officially recognised in the 18th Edition.^[4][5] Treat "zone 3" as an informal name for everywhere else.

What an IP rating means

An IP rating (Ingress Protection) says how well a product's enclosure keeps out solids and water. The code is defined by the international standard IEC 60529, published in Europe as EN 60529.^[6] It has two digits.

• First digit (solids), 0 to 6. 2 protects against fingers; 4 against wires over 1 mm; 5 is dust protected; 6 is dust-tight.^[6]
• Second digit (water), 0 to 9. 4 means splashing from any direction; 5 means jets from a 6.3 mm nozzle; 7 means immersion, with one example being a phone rated IP67 immersed in 1 m of fresh water for up to 30 minutes.^[6]
• X means no rating has been assigned for that digit, so "IPX4" says nothing about solids.^[6]

Ideal Home sums it up: the higher the number, the more resistant the product.^[7] Two cautions. Tests use fresh water, so ratings say nothing about salt water or chemicals.^[6] And an IP rating describes the enclosure when the product is correctly installed, so it is not a licence to fit a product anywhere.

What the ratings need to be, zone by zone

SELECT's guide gives these minimums: IPX7 in zone 0, IPX4 in zone 1 and IPX4 in zone 2. It also says that in zone 0 only fixed, permanently connected equipment is allowed, supplied by very low voltage (SELV) not exceeding 12 V AC or 30 V DC. Zone 1 may contain electric showers, pumps, ventilation, towel rails, water heaters and luminaires; zone 2 may contain shaver supply units complying with BS EN 61558-2-5 where direct spray is unlikely, and other IPX4 equipment.^[3]

Ideal Home gives the same minimums and adds that IPX5 is required in zones 1 and 2 where water jets are present, such as a power shower.^[7] Screwfix also gives IPX5 where jets are present.^[4] Crosswater says zone 0 needs IP67 and zones 1 and 2 need IP44, naming BS 7671:2018+A2:2022 as the standard.^[8] These differences are real (see the comparison diagram). They exist because retailers simplify, so the fitting's label and your electrician's judgement are what count.

Worked example: a 2.4 m × 1.9 m bathroom with a 2.4 m ceiling

Take a bathroom 2.4 m long and 1.9 m wide, with a 1.7 m × 0.7 m bath in the top-left corner and a basin by the door. The bath is zone 0 inside and zone 1 above it, up to 2.25 m. Zone 2 extends 0.6 m beyond the bath's open edges, so along the 2.4 m wall it reaches 1.7 + 0.6 = 2.3 m, and across the room it reaches 0.7 + 0.6 = 1.3 m. Only a strip 0.6 m deep (1.9 − 1.3) along the door wall is clear of the zones across most of the room.

Now the lights. The ceiling is 2.4 m, which is above the 2.25 m limit, so a surface ceiling light sits above the zones. Ideal Home reports that Electrical Safety First still recommends IP44 above 2.25 m.^[7] In a bathroom that is a sensible choice. A wall light on the wall above the bath, below 2.25 m, would be in zone 1 and would need at least IPX4. Your electrician will confirm the zones, choose the circuit and protection, and certify the work. Do not move a light without that check, and do not assume the ceiling height matches the 2.25 m limit in your house.

Residual current protection and sockets

SELECT's guide says additional protection by 30 mA RCDs is required for all low-voltage circuits serving the room, and that 13 A socket-outlets are only permitted outside the 2.5 m boundary.^[3] Screwfix recommends RCD protection for all bathroom electrical installations.^[4] Shaver supply units are a special case: SELECT says shaver supply units complying with BS EN 61558-2-5 may be used in zone 2 where direct spray is unlikely.^[3] All of this is for the electrician to design and test.

Is it notifiable? Approved Document P

Approved Document P (2013 edition) lists three notifiable categories: installing a new circuit, replacing a consumer unit, and any addition or alteration to existing circuits in a special location, which includes a room with a bath or shower. It also says installations should be designed, installed, inspected and tested in accordance with BS 7671.^[1] In practice, a registered electrician will handle any notification and give you a certificate. Ask for it, and keep it with your house papers.

Choosing fittings you will not regret

• Read the label, not just the listing. Look for the IP code on the product and in the instructions.
• Match the fitting to the zone, not the other way round.
• Plan for steam. Bathrooms are humid even outside the zones, so IP44 is a sensible floor for most fixtures.^[7]
• Choose warm, dimmable light for relaxing and brighter light near the mirror.
• Keep decorative plaster outside the wet areas. See our guide to ceiling roses in a bathroom or kitchen for what plaster can and cannot do in steamy rooms.

Quick reference: zones and minimum ratings

From SELECT's guide unless stated. Confirm with a qualified electrician.

Common mistakes

• Buying by looks first. Check the IP rating and zone before you fall in love with a fitting.
• Trusting a single website. Sources differ in detail.
• Forgetting the shower head height. Zones are measured to the highest fixed shower head if it is higher than 2.25 m.^[3]
• DIY wiring. It must be a qualified electrician.^[1]
• Ignoring steam outside the zones.

Glossary

• BS 7671: the UK wiring standard (the IET Wiring Regulations); Section 701 covers bath and shower rooms.^[3]
• IP rating: a two-digit code for protection against solids and water.^[6]
• SELV: separated extra-low voltage, such as 12 V, from a safety source outside the zones.^[3]
• RCD: residual current device that cuts power quickly when it detects a fault.
• Luminaire: a light fitting.
• Special location: in Approved Document P, a room with a bath or shower, among others.^[1]

What to do next

Draw your plan, shade the zones and list the lights you want, then book a qualified electrician. If you are tiling the walls, our guide to choosing a tile layout helps with the finish, and our what bulb to use in a plaster wall light explains bulb choices for dry rooms.

Keep reading

• Can you put a ceiling rose in a bathroom or kitchen?
• How to choose a tile layout
• What bulb for a plaster wall light
• How to layer lighting in a living room
• Wall light height and spacing

Shop the look

Bedside Wall LightDuchess Ceiling RoseAcanthus Overdoor Pediment — 35 in

Frequently asked questions

What are the bathroom lighting zones?

Zone 0 is inside the bath or shower tray. Zone 1 is above it up to 2.25 m. Zone 2 extends 0.6 m beyond zone 1, also up to 2.25 m. Everything else is outside the zones. A qualified electrician confirms the zones in your room.

What IP rating do I need for bathroom lights?

SELECT's guide to BS 7671 gives IPX7 for zone 0 and IPX4 for zones 1 and 2. Some guides recommend IPX5 where jets are used, and IP44 is often advised for ceiling lights. Your electrician confirms what applies.

What does IP44 mean?

The first 4 means protection against objects over 1 mm. The second 4 means protection against splashing water from any direction.

Can I install a bathroom light myself?

No. Fixed wiring in a bathroom must be done by a qualified electrician. This guide only explains the zones and ratings so you can plan and choose fittings.

Do ceiling lights in a bathroom need an IP rating?

Ideal Home reports that Electrical Safety First still recommends IP44 for lights above 2.25 m. Ask your electrician.

Is bathroom electrical work notifiable?

Under Approved Document P, a new circuit, a consumer unit replacement and any addition or alteration to existing circuits in a room with a bath or shower are notifiable. A registered electrician can handle this.

Can I put a wall light above a bath?

Only if it is rated for the zone (at least IPX4 in zone 1) and installed by a qualified electrician. Decorative plaster fittings without an IP rating should stay out of wet areas.

What is the difference between IPX4 and IP44?

IPX4 gives a water rating only; IP44 also guarantees protection against objects over 1 mm. IP44 is therefore a slightly stronger claim.