The four measurements that decide it
- Opening height. The tallest fixed point wins: usually the rocket launcher, a folded bimini, the anchor light or the outboard tilted. Tape from the slab to that point with the trailer hooked up level, then remember the door's own tracks and seals steal a little from the raw opening. If it's tight on paper, it's stuck in practice.
- Opening width. Trailer mudguards and mirror-to-mirror beam, not the hull, set the number. A wide-beam tinny on a braked trailer wants more air each side than the brochure suggests.
- Headroom inside. A standard sectional needs roughly 300 to 400 mm of clear ceiling above the opening for its tracks; a roller drum wants around 200 to 250 mm at the lintel. High-lift track configurations can buy a taller opening in a tall garage, and that's often the trick that gets a big rig inside.
- The straight run. A boat backs in on a line. Side access doors, the pier between double openings, and where the jockey wheel swings all matter. One wide opening often beats two narrow ones for a boat household, and that's a structural conversation we're happy to have honestly.
Sectional or roller, when there's a hull involved
A sectional door slides back overhead, which is exactly where a rocket launcher wants to be, so track layout gets planned around the boat's height, not just the ceiling. A roller stays compact in its drum at the lintel and leaves the ceiling clear, which can win in a tall, shallow garage. Neither is "the boat door"; the measure decides, which is why the measure is the first visit and it's free.
While we're talking boats and doors
- A garage that opens for the boat every weekend cycles its door far more than a commuter's, in the saltiest air in the region. That's the exact profile the coastal service exists for.
- Safety beams earn their keep in a boat household: trailers, drawbars and kids' feet spend a lot of time exactly where the door closes. We test the beams as part of every service.
- Washing the boat down after a run? Give the door tracks the last thirty seconds of the hose. Salt that doesn't sit can't pit.
What to have ready at the enquiry: slab-to-highest-point height, trailer width at its widest, and roughly how tall the garage ceiling is. Three numbers, and the measure visit arrives already knowing the shape of the answer.