If your team works outdoors in the UK, wet-weather kit isn't optional. But "waterproof" gets used loosely, and two jackets that both claim it can perform very differently. Understanding a few simple terms takes the guesswork out of choosing.
Water-resistant vs waterproof: not the same thing
This is the distinction that trips people up most:
- Water-resistant (or water-repellent) — sheds light rain and showers for a while, then eventually wets through. Think softshells and many everyday jackets.
- Waterproof — built to keep water out in sustained, heavy rain, usually with a coated or membrane fabric and sealed seams.
If people are out in real weather for hours, water-resistant won't cut it — you need a genuine waterproof.
The hydrostatic head (that "mm" number)
Waterproofing is often measured as a hydrostatic head, given in millimetres (mm). In simple terms, it's how tall a column of water the fabric can hold back before it leaks. A higher number means more waterproof. As a rough guide:
| Rating | Roughly means |
|---|---|
| 1,500–5,000mm | Handles light-to-moderate rain; fine for short exposure |
| 5,000–10,000mm | Stands up to steady rain and general outdoor work |
| 10,000mm+ | Copes with heavy, prolonged rain and pressure points like shoulders and seat |
These are general guides, not hard rules — always check the specific garment's stated rating.
Breathability: staying dry from the inside too
A jacket that keeps rain out but traps sweat leaves you damp anyway. Breathability is how well a fabric lets moisture vapour escape, often given as a g/m²/24hr figure (higher = more breathable). For active outdoor work, breathability matters almost as much as the waterproof rating — it's the difference between comfortable and clammy.
The details that make a jacket actually waterproof
The fabric rating is only half the story. Look for:
- Taped or welded seams — stitching makes holes; sealing the seams stops water sneaking through them.
- Storm flaps over zips — zips are a common leak point without a covering flap.
- A DWR finish — a durable water-repellent coating that makes rain bead and roll off the surface.
- Adjustable cuffs and hem — to seal out driving rain at the openings.
Matching the kit to the work
- Occasional light showers, mostly sheltered — a water-resistant softshell is usually enough.
- Regular outdoor work in changeable weather — a breathable waterproof with taped seams.
- All-day exposure in heavy rain — a higher-rated waterproof, ideally with a hood and sealed openings.
Not sure where a softshell fits into all this? Our softshell vs fleece guide covers how those layers compare.
Brand it and it still performs
Embroidery puts small needle holes through the fabric, so on a fully waterproof shell we'll advise on logo placement and backing, or suggest print or heat-applied branding, to protect the waterproofing while still giving your team a smart, recognisable look. Weighing your options? See our embroidery vs print guide.
Ready to sort your team's wet-weather kit? Browse workwear for business or tell us the conditions your team faces and we'll recommend the right level.
