Indoor vs Outdoor Lighting: What's the Difference and Why Does It Matter?

When you're shopping for new light fittings, it's easy to assume that a light is a light — if it looks right, it'll work anywhere. But there's actually an important distinction between indoor and outdoor lighting, and using the wrong type in the wrong place can be dangerous, wasteful, and costly.

In this guide, we'll walk you through the key differences between indoor and outdoor lighting, explain what IP ratings mean, and help you choose the right fittings for every space in and around your home.

Why Can't You Use Indoor Lights Outside?

Indoor light fittings are designed to operate in a controlled environment — sheltered from rain, condensation, extreme temperatures, and direct sunlight. They're not built to withstand moisture, which is the biggest risk when it comes to electrical safety outdoors.

Using an indoor light fitting outside — even under a covered porch or pergola — can allow water to enter the fitting over time. This creates a serious risk of short circuits, electrical faults, and in the worst cases, fire or electric shock.

Outdoor light fittings, on the other hand, are manufactured to much stricter standards. They're built with weatherproof seals, UV-resistant materials, and corrosion-resistant finishes that allow them to perform reliably in the British climate year-round.

Understanding IP Ratings

The most important thing to look for when buying outdoor lighting is the IP rating. IP stands for Ingress Protection, and it's a two-digit code that tells you how well a fitting is protected against solids (like dust) and liquids (like rain).

How to read an IP rating:

The first digit refers to protection against solid particles, on a scale of 0–6. The second digit refers to protection against water, on a scale of 0–8.

For outdoor use in the UK, you generally want a minimum rating of IP44, which means the fitting is protected against solid objects larger than 1mm and against water splashing from any direction. For fittings in more exposed locations — like directly on an exterior wall facing the elements — IP65 or above is recommended, as this provides full dust protection and protection against low-pressure water jets.

Quick IP rating guide:

IP20 — Suitable for dry indoor use only. Not suitable for bathrooms or outdoors.

IP44 — Protected against splashing water. Suitable for covered outdoor areas like porches and pergolas.

IP65 — Fully dust-tight and protected against water jets. Suitable for exposed outdoor walls, garden posts, and driveways.

IP67/IP68 — Suitable for temporary or permanent submersion. Used for garden pond lights and in-ground fittings.

What About Indoor Lighting Near Moisture?

It's not just outdoors where IP ratings matter. Bathrooms and kitchens also require fittings with appropriate moisture protection, and the UK has specific building regulations (BS 7671) that define 'zones' within a bathroom, each with minimum IP rating requirements.

As a general rule, any light fitting within 60cm of a bath or shower must be at least IP44. Always check the IP rating when shopping for bathroom lighting, not just outdoor fittings.

Can Outdoor Lights Be Used Indoors?

Yes — and this is actually a popular interior design choice. Outdoor-rated wall lights have a robust, industrial look that works beautifully in hallways, utility rooms, and even living spaces. Because they exceed the requirements for indoor use, there's no safety concern in using them inside.

Some of our most popular wall lights blur the line between indoor and outdoor — versatile enough to work in both settings while adding serious style to any space.

Choosing Outdoor Lighting for Your Home

When selecting outdoor lighting, think about three things: function, position, and style.

Function

Are you lighting a pathway for safety? Illuminating a patio for entertaining? Adding security lighting to a driveway? Each of these calls for a different type of fitting — from low-level post lights to motion-sensor wall lights to floodlights.

Position

How exposed is the location? A light under a deep porch overhang needs less protection than one mounted on a south-facing exterior wall. Use your IP rating as a guide — the more exposed the location, the higher the rating you need.

Style

Outdoor lighting is often the first thing visitors see when they arrive at your home. It sets the tone. Whether you prefer a sleek, contemporary look or something more traditional, it's worth choosing outdoor fittings that complement your home's architecture and your indoor lighting scheme.

Explore our full range of outdoor lighting — all IP-rated and designed to perform in the UK climate while looking exceptional year-round.

Final Thoughts

The difference between indoor and outdoor lighting comes down to one thing: protection. Outdoor fittings are built to handle moisture, temperature changes, and UV exposure that would quickly damage an indoor fitting. Always check the IP rating before buying, and when in doubt, go higher rather than lower.

If you're unsure which fitting is right for your space, our team is always happy to help. Get in touch via our contact page and we'll point you in the right direction.

Looking for inspiration? Browse our wall lights collection — many of which are suitable for both indoor and outdoor use.