IP40 vs IP65 Enclosures Explained

IP40 enclosures are suitable for dry indoor locations. IP65 enclosures are fully dust-tight and protected against water jets — required for outdoor installations, garages with wash-down risk, or anywhere moisture may be present. Getting this wrong creates a compliance and safety issue.

The IP (Ingress Protection) rating on an electrical enclosure tells you exactly how well it is sealed against solid particles and water. It is not a marketing specification — it is a defined test standard (BS EN 60529) with specific pass/fail criteria for each rating. Choosing the correct IP rating for the installation environment is a BS 7671 requirement and directly affects both safety and long-term reliability.

How to read an IP rating

IP code	First digit — solid particle protection	Second digit — water protection
IP20	Protected against fingers and objects >12.5mm	No water protection
IP40	Protected against solid objects >1mm (wires, screws)	No water protection
IP44	Protected against solid objects >1mm	Protected against water splashes from any direction
IP65	Fully dust-tight (no ingress permitted)	Protected against water jets from any direction
IP66	Fully dust-tight	Protected against powerful water jets
IP67	Fully dust-tight	Protected against temporary immersion to 1m

IP40 — indoor dry locations

IP40 metal consumer units and distribution boards are the standard for indoor domestic and commercial installations — inside a house, in a dry utility cupboard, on a wall in a dry plant room or office. They provide adequate protection against accidental contact with live parts and against small solid objects, but offer no protection against water ingress. The standard WCED metal consumer units (WME series) are IP40 rated.

IP40 is NOT suitable for garages that may be washed down, outbuildings with condensation risk, outdoor locations of any kind, or anywhere that water vapour, rain, or spray may reach the enclosure.

IP65 — outdoor and damp locations

IP65 provides complete dust exclusion and protection against water jets from any direction. This is the minimum requirement for any outdoor electrical enclosure and is also required for garages, car ports, outbuildings with humidity or condensation risk, and commercial environments where cleaning involves water spray.

The WCED WP series provides IP65 rated polycarbonate enclosures in sizes from 4-way to 16-way, designed for outdoor EV charging, solar, and heat pump sub-board applications. The WPEVCU32BSP is an IP65 EV connection unit with integrated SPD and Type B RCD specifically for outdoor EV charger installations.

Which IP rating do I need?

Location	IP rating required	WCED product
Inside house — dry utility room, hallway, kitchen	IP40 minimum	WME series metal consumer units
Garage — dry, not washed down	IP40 acceptable	WME series
Garage — washed down or condensation risk	IP65 recommended	WP series IP65 enclosures
Outdoor — EV charger, solar sub-board	IP65 minimum	WP series or WPEVCU
Commercial — food prep, washdown areas	IP65 minimum	WP series
Outbuilding with humidity risk	IP65 recommended	WP series IP65 enclosures

Shop WCED IP40 and IP65 Enclosures

Metal IP40 consumer units and IP65 polycarbonate enclosures — fully assembled options available. In stock.

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Frequently Asked Questions

Can I use an IP65 enclosure indoors?

Yes — IP65 can be used anywhere IP40 is specified. The higher protection level does not cause any problems indoors; it simply provides more protection than is strictly required. The main considerations for indoor use are cost (IP65 enclosures are typically more expensive) and aesthetics (polycarbonate IP65 units have a different appearance from metal IP40 boards).

Does the IP rating cover the cable entry points?

Only when correctly sealed. IP65 enclosures rely on properly fitted cable glands or conduit entries to maintain their rating. Loose or unsealed cable entries defeat the IP protection. All cable entries in an IP65 enclosure must use appropriately rated glands or fittings to maintain the enclosure's IP65 rating.

What IP rating is required for a bathroom?

In bathroom zone 1 (inside the bath or shower), IP45 minimum is required. In zone 2 (within 0.6m of the bath or shower), IP44 minimum is required. Consumer units and distribution boards are not permitted in bathroom zones — they must be located outside the defined zones, where IP40 is typically acceptable.

Further reading:
Metal vs plastic enclosures — which should you use?
Fully assembled consumer units explained
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