IP Ratings Explained: Which LED Driver Do You Need for Bathrooms, Kitchens & Outdoors?
Key Takeaways
- IP ratings tell you how well an LED driver is protected against dust and water — the first number is dust, the second is water.
- Bathrooms are split into legal "zones" in the UK, and each zone has a minimum IP rating you must meet.
- Kitchens generally need IP20 drivers for dry areas, but IP44 or higher near sinks and hobs.
- Fully outdoor installations need IP65 or IP67 drivers as a minimum, with IP67 needed for anything that could be submerged or exposed to jet washing.
- Using the wrong IP rated LED driver is a common cause of premature failure, electrical faults, and — in bathrooms — a building regulations breach.
Why IP Ratings Actually Matter (Not Just a Spec Sheet Number)
If you've ever shopped for an LED transformer and seen codes like IP20, IP44, IP65 or IP67 sitting in the product title, you've probably wondered whether it really matters which one you buy. It does — more than almost any other spec on the page.
An LED driver converts mains voltage into the low voltage your LED strip, bulb, or fixture actually needs to run. Like any electrical component, it has a circuit board, soldered joints, and capacitors that don't get along well with moisture or dust. The IP (Ingress Protection) rating is a standardised European test result — defined under IEC 60529 — that tells you exactly how much solid and liquid intrusion a product is built to withstand before it fails or becomes unsafe.
Get this wrong in a bathroom and you're not just risking a blown driver. You're risking a genuine safety hazard and, in the UK, a breach of Part P of the Building Regulations.
How to Read an IP Rating (IP Followed by Two Numbers)
| Position | What It Measures | Range |
|---|---|---|
| First digit | Protection against solid objects and dust | 0 (no protection) to 6 (totally dust-tight) |
| Second digit | Protection against liquid/water ingress | 0 (no protection) to 9K (high-pressure, high-temp jets) |
So IP65 means: dust-tight (6), and protected against low-pressure water jets from any direction (5). IP20 means: protected against solid objects larger than 12.5mm (like fingers) but offers no water protection at all.
This is the part people get wrong most often — a higher first number doesn't automatically mean better water protection, and vice versa. You need to check both digits separately.
Full IP Rating Comparison Table
| IP Rating | Dust Protection | Water Protection | Typical Use Case | Suitable Location |
|---|---|---|---|---|
| IP20 | Protected against objects >12.5mm (fingers, tools) | None | Standard indoor driver, dry areas only | Living rooms, bedrooms, hallways, dry kitchens |
| IP44 | Protected against objects >1mm | Splash-proof from any direction | Light moisture exposure | Kitchen worktops, covered porches, utility rooms |
| IP45 | Protected against objects >1mm | Protected against low-pressure water jets | Light rain exposure | Covered outdoor areas, garages, sheds |
| IP65 | Totally dust-tight | Protected against low-pressure water jets from any direction | General outdoor use | Garden lighting, exterior walls, car ports |
| IP67 | Totally dust-tight | Protected against temporary immersion (up to 1m, 30 mins) | Heavy rain, wet ground contact | Outdoor flowerbeds, pond edges, driveways, fully exposed installs |
| IP68 | Totally dust-tight | Protected against continuous submersion | Permanent submersion | Fountains, fully submerged pond lighting |
Which LED Driver Do You Need? Room-by-Room Breakdown
1. Bathrooms — The Strictest Rules in the House
UK bathrooms are legally divided into zones, and each zone has a minimum required IP rating for any electrical fitting, including the driver powering your lights.
| Bathroom Zone | Location | Minimum IP Rating Required |
|---|---|---|
| Zone 0 | Inside the bath or shower itself | IP67 or IP68 |
| Zone 1 | Directly above the bath/shower, up to 2.25m | IP65 |
| Zone 2 | 0.6m beyond the bath/shower edge | IP44 |
| Outside Zones | Beyond 0.6m from any water source | IP20 acceptable |
If you're fitting downlights over a shower, you need at minimum an IP65-rated driver and fitting. If the driver itself is mounted in the loft space above (outside the zone), it can often be IP20 — but the fitting in the zone still needs to meet the zone requirement. This is the single most common bathroom lighting mistake we see: people buy an IP65 light fitting but pair it with an IP20 driver mounted too close to the wet zone.
Our recommendation: for any bathroom job, default to IP65 unless you're certain the driver location is fully outside Zone 2.
2. Kitchens — Mostly Dry, But Not Everywhere
Kitchens are not legally zoned like bathrooms, but common sense (and good practice) still applies.
- General ceiling lighting, away from water: IP20 is fine.
- Under-cabinet lighting near sinks or hobs: IP44 minimum — splashes from washing up or steam from pans are a real risk.
- Outdoor kitchens or covered patio cooking areas: IP65, treated the same as outdoor installations.
3. Outdoor Lighting — Don't Underestimate British Weather
Outdoor installations need to handle rain, condensation, frost, and in some cases standing water.
- Wall-mounted, covered porch or eave lighting: IP44–IP45 is usually sufficient if it's sheltered from direct rain.
- Garden lighting, pathway lights, fully exposed wall lights: IP65 minimum.
- Anything near or in contact with soil, flower beds, or potential flooding: IP67.
- Pond, fountain, or fully submerged lighting: IP68 only.
Common Mistakes That Cause LED Driver Failure
- Using an IP20 driver outdoors "because it's in a junction box." A standard junction box isn't a substitute for a properly rated, sealed driver — water finds a way in through cable glands and seams over time.
- Mismatching the fitting's IP rating with the driver's IP rating. Your weakest link determines your overall protection — an IP65 fitting wired to an IP20 driver in the same wet zone is still an IP20 system.
- Ignoring dust in commercial or workshop environments. The first digit matters too — a dusty workshop or garage needs at least IP54 even with zero water exposure.
- Overlooking heat buildup. Higher IP-rated, sealed drivers run hotter because they can't "breathe" — always check the wattage headroom and avoid running a driver at 100% of its rated load in an enclosed, weatherproof housing.
Constant Voltage vs Constant Current: Does IP Rating Work the Same Way for Both?
It's worth clarifying a related point of confusion before we go further: IP rating and driver type (constant voltage vs constant current) are two completely separate specifications, and you'll need to get both right.
- Constant Voltage (CV) drivers output a fixed voltage (commonly 12V or 24V) and are used for most LED strips, modules, and standard fittings where multiple LEDs are wired in parallel.
- Constant Current (CC) drivers output a fixed current (measured in mA) and are typically used for single high-power LEDs or COB modules wired in series, such as some downlights and floodlights.
Both CV and CC drivers are manufactured across the full range of IP ratings, from IP20 right through to IP68. So when you're specifying a driver, you actually need to answer two questions at once: "What type of LED am I driving?" and "What environment will this driver sit in?" Getting the IP rating right but the driver type wrong is just as likely to cause a failure — usually a much faster one, as mismatched current can burn out LEDs within hours.
Wattage, Headroom and Why Sealed Drivers Need Extra Care
One detail that's easy to overlook once you've picked the correct IP rating is wattage headroom. Sealed, weatherproof drivers (IP65 and above) are housed in fully enclosed casings, often filled with a potting compound for extra protection. This makes them excellent at keeping water and dust out, but it also means they can't dissipate heat as efficiently as a ventilated IP20 driver sitting in open air.
As a rule of thumb:
- For IP20 drivers in well-ventilated indoor locations, running at up to 80% of the rated wattage is generally safe.
- For IP65–IP67 outdoor or bathroom drivers, we recommend keeping the load to around 70-75% of the maximum rated wattage, particularly if the driver will be mounted in direct sunlight or a poorly ventilated enclosure (such as inside a garden wall cavity).
- Always check the manufacturer's derating chart if one is provided — ambient temperature has a real effect on how much load a sealed driver can safely handle long-term.
Running a sealed driver consistently at its absolute maximum rating shortens its working life considerably, even if the IP rating itself is correct for the environment. This is one of the most common reasons customers report "premature" driver failure when, in fact, the IP rating wasn't the problem — overloading was.
Step-by-Step: How to Choose the Right IP Rated LED Driver
If you're still not sure which driver to order, run through this checklist before you buy:
- Identify the exact location. Is it fully indoors and dry, occasionally damp, fully exposed to weather, or potentially submerged?
- If it's a bathroom, confirm the zone. Measure the distance from the nearest bath, shower, or basin and check it against the zone table above. When in doubt, treat it as the more demanding zone.
- Check both digits of the IP rating, not just the headline number. A driver advertised as "IP44" with no further detail should still list both the solid and liquid protection figures in the spec sheet.
- Match the driver type to your LED fitting. Confirm whether your strip, bulb, or module needs constant voltage or constant current, and at what voltage/current.
- Calculate your wattage requirement, then add headroom. Add up the wattage of everything the driver will power, then choose a driver rated at least 20-25% above that total — more if it will be sealed and outdoors.
- Confirm dimming compatibility if needed. Not all IP rated drivers support dimming, and dimmable drivers often need a matching dimmer switch type (leading-edge vs trailing-edge) to function correctly.
- 7.Plan the cable route and connections. Even a correctly IP-rated driver can fail if connectors and cable glands in the wet zone aren't also rated to match — the whole chain needs to meet the standard, not just the driver itself.
- If it's bathroom or fixed outdoor wiring, get it signed off by a qualified electrician. This is a legal requirement under UK Building Regulations Part P for most bathroom and many outdoor electrical installations.
Maintenance Tips to Extend the Life of Your LED Driver
Even a correctly specified, properly installed driver benefits from a bit of ongoing attention:
- Check seals and gaskets annually on outdoor IP65+ drivers, particularly after extreme weather, as UV exposure and temperature swings can degrade rubber seals over several years.
- Keep vents clear on IP20 indoor drivers — dust buildup around ventilation slots is one of the most common (and easily preventable) causes of overheating indoors.
- Inspect cable entry points where wires enter a sealed outdoor driver housing; this is the single most common failure point for water ingress, even on a correctly rated unit, if the gland wasn't tightened or sealed properly during installation.
- Avoid painting or covering vented drivers, which can trap heat and cause early failure even if the IP rating itself is appropriate.
- Keep your receipt and note the IP rating and wattage of every driver you install — if a fitting needs replacing in a few years, this saves time matching specifications again.
A Note on UK Weather and Real-World IP Performance
It's worth being realistic about UK conditions specifically. Manufacturers' IP ratings are tested under controlled laboratory conditions, not years of freeze-thaw cycles, prolonged damp, or driving rain at an angle into a wall-mounted fitting. In practice, many UK installers recommend specifying one IP level higher than the legal minimum for genuinely exposed, north or west-facing outdoor installations, simply because real-world weather exposure over several British winters is harsher than a single lab test. This is a judgement call rather than a regulation, but it's a pattern worth knowing if you want a driver that lasts a decade rather than two or three years.












