Rain gear sorts into three buckets by construction. PVC, polyurethane-coated polyester, and breathable membrane. Each one has a use case. Buying the wrong one for your work is how guys end up wet.
PVC. Heavy plastic, fully waterproof, won't breathe at all. The yellow rain suits you've seen on construction sites for forty years. PVC is bombproof against water — you can stand in a downpour for eight hours and stay dry. It's also a sauna. Any activity heavier than walking and you're wet from the inside instead of the outside. PVC is the right answer for short, intense, stationary work in heavy rain — flagger duty, low-effort outdoor monitoring, very wet conditions where you need full coverage and don't move much.
Polyurethane-coated polyester. Lighter, somewhat breathable through seam construction and venting more than through the fabric itself. Most consumer rain jackets are PU-coated. They handle moderate rain well, breathe better than PVC, and work for short to medium activity. They wear out faster than PVC — the coating eventually cracks at flex points.
Breathable membranes — Gore-Tex and similar. Microporous fabric that lets water vapor (sweat) escape while blocking liquid water (rain) from coming in. These breathe enough that you can work hard in them without soaking yourself from the inside. They cost three to five times what PU rain gear costs. They wear out the fastest of the three because the membrane is delicate — abrasion, oils, and bad washing all break it down.
"Once your boots fill from rain running down your legs, you'll wish you'd bought the pants."
Match the construction to the work. Stationary outdoor work, hard rain, low budget — PVC. General outdoor work in moderate rain, mid-budget — PU. Active work, long hours in the rain, willing to spend — Gore-Tex or equivalent.
Seam taping matters more than the marketing on the front. Look at the seams from the inside. If they're sealed with a tape strip across the stitching, the seams are waterproof. If you see raw stitching from the inside, water comes through the needle holes within the first hour, regardless of how waterproof the fabric is. Cheap rain gear cuts this corner.
One more thing — overpants. People buy a rain jacket and skip the pants because pants seem optional. Once your boots fill from rain running down your legs, you'll wish you'd bought the pants. Bib overalls in rain gear are even better — no waist gap to leak through.
Carhartt and Helly Hansen are the two we carry most of. Helly's Impertech line is the workhorse for marine and heavy industrial. Carhartt's storm defender line covers most general construction needs.