Bathroom Lighting Zones and Regulations

One of the areas of the house we get asked the most questions about is the bathroom or wet room. Around the vast majority of your home you’re free to add which ever light fittings take your fancy. However in the bathroom things become a little more complex as there are specific regulations that govern what type of lights can and can’t be used.

This guide will take you through the key points you need to be aware of when installing lighting in a bathroom. It is however not an ‘Installation Guide’ and before proceeding you should first refer to the current edition of the IEE Wiring Regulations and/or consult a qualified electrician.

When purchasing lights for a bathroom you need to ensure you select a fitting with the correct IP rating for the bathroom zone in which it is to be placed.

"Bathroom Zones?"

"IP Ratings?"

"What on earth are they?"

We’re glad you asked, read on and we’ll explain all! 

Bathroom Lighting Zones Explained

For the purpose of lighting a bathroom is broken down into zones. Each zone is determined by how exposed it is to water and therefore how much protection from water a light fitting placed their requires.

When choosing lighting for a bathroom you first need to understand what zone its intended position will be classified as and then select the appropriate fitting based on its IP rating (which we cover further on).

The diagram below illustrates the bathroom lighting zones;

Bathroom Lighting Zones Diagram


Zone 0 – This zone covers the areas inside the bath or shower tray. If you do decide to fit lights here they need to be a minimum of IP67 which means that they are safe to be fully immersed.  They also need to be low voltage.

Zone 1 – Includes the area directly above the bath or shower tray to a height of 2.25m. Lights being fitted within this area must have an IP rating of IP44 or better which means they are protected against water spray and splashing from any direction.

Zone 2 – Covers the area 0.6m outside the perimeter of the bath. This area also requires a light fitting to be IP44 of better. It’s also considered best practice to incorporate the sink into zone 2 and apply the same perimeter and light fitting requirements as you would the bath.

Zone 3 – Is everywhere else in the bathroom and covers the areas where lighting is highly unlikely to come into contact with water. There are no regulations regarding this area.

Now you are a master of the bathroom zones you now need to understand the IP rating system that governs which lights can be placed in each zone.

IP Explanation and Ratings

The IP ratings are designed to make it easier for people to understand how well protected a light fitting is. Whether they do or not is perhaps a little debateable, however with a bit of explanation they are relatively easy to follow.

An IP code consists of thee parts;

IP – All codes start with IP and this stands for Ingress Protection. This basically means how well protected the light fitting is.

Digit One – Refers to solid particle protection or how well the light fitting is protected against solid particles such as dust and dirt. The higher the number the better protected the light fitting is. See table 1 below for a complete breakdown.

Digit Two – Refers to liquid ingress protection or how well the lighting fitting is protected against water. Again the higher the number the more protection the light fitting provides. See table 2 below for a complete breakdown.

IP Ratings Tables


Summing Up

At first glance bathroom lighting zones and regulations can seem more than a little confusing. However if you spend some time understanding the zones and how they apply to your bathroom it’s just a case of choosing light fittings with an appropriate IP rating.

It is always advisable to use a properly trained expert to ensure that any bathroom light fittings are completed to the required standards.

If you need any further help or advice on this, or any other lighting topic, then our team are standing by to answer your questions. Please visit out contact us page for details of how you can get in touch.