Metal enclosures are a common choice for outdoor electrical and electronics installations because they hold up well against sun exposure, weather, and physical impact — you don't have to worry about a metal enclosure warping or degrading under UV exposure the way some plastics can.
But 'metal' isn't one material — steel and stainless steel behave very differently outdoors, and the right choice depends on your environment, budget, and required protection rating.
What to Consider Before Choosing an Outdoor Metal Enclosure
A few factors decide what “right” looks like for your installation:
● Weather and moisture exposure — rain, humidity, and washdown all call for different levels of water protection.
● Corrosion risk — coastal air, chemical exposure, and frequent cleaning put more demand on the material.
● Internal heat buildup — direct sun exposure can raise internal temperatures enough to affect sensitive components.
● Security — tamper-resistant hardware and locking covers matter for equipment installed in accessible outdoor locations.
Matching the right protection level to your environment is covered in more depth in our NEMA enclosure ratings guide and our IP65 vs IP66 enclosures comparison.
Metal Enclosure Material Options for Outdoor Use
Steel Enclosures
Steel is a practical, cost-effective option for outdoor installations, especially when it's powder-coated for added surface protection. It offers the rigidity and impact resistance you'd expect from a metal enclosure, at a lower cost than stainless steel — a good fit when the environment isn't especially corrosive.
If you're curious how steel actually holds up mechanically, our How Strong Is Carbon Steel guide breaks down yield strength, tensile strength, and what those numbers actually mean for an enclosure.
Stainless Steel Enclosures
Stainless steel is the step up when corrosion resistance matters more — coastal sites, chemical exposure, and frequent washdown are all places where stainless earns its higher price tag.
Worth noting: stainless steel construction doesn't automatically mean an enclosure meets a specific NEMA or IP rating. That protection depends on the complete enclosure — gasket, door design, cable entries, and construction — not the material alone.
See What Is 304 Stainless Steel for the properties and grades, including when the extra cost of 316 over 304 is actually worth it.
Metal vs. Other Materials for Outdoor Use
If you're still deciding between a metal enclosure and a non-metallic alternative, our Metal vs Plastic Electrical Enclosure comparison covers that decision in more detail. Fiberglass is worth a look too — it's non-conductive and holds up well in wet or chemically aggressive environments where metal would otherwise need heavier corrosion protection. Our Fiberglass vs Stainless Steel Enclosures comparison walks through when that trade-off makes sense.
Benefits of Metal Enclosures for Outdoor Use
● Resists UV degradation — won't warp, crack, or fade the way some plastics can under prolonged sun exposure
● Impact and tamper resistant — holds up better against accidental knocks, tools, and casual vandalism
● Naturally blocks RFI/EMI — a side benefit for equipment sensitive to electrical interference
● Corrosion resistant when material and coating are matched to the environment
Find the Right Outdoor Metal Enclosure
Ready to find the right enclosure for your outdoor application? Explore Saipwell's metal and stainless steel enclosures, available in multiple sizes and configurations for outdoor industrial and commercial use.
