Boat and Yacht Mattresses Cut to Size
Nothing on a boat is square. A V-berth is a triangle with the point cut off, a quarter berth narrows into the hull, and the mattress usually has to come out through a hatch smaller than it is.
Template it, do not measure it
For a berth with any curve in it, measurements are not enough. Make a template:
- Lay cardboard or thick paper over the whole berth base.
- Push it firmly into every edge and crease the paper against the hull.
- Cut along the crease.
- Test-fit the template. It should drop in with a couple of millimetres to spare all round.
- Mark which edge is the head, which is the bow side, and which face is up.
- Photograph it flat, with a tape measure laid across it in both directions.
A template answers every question at once. A list of four numbers for a curved berth never does.
Common berth shapes
- V-berth. Tapered, often with a filler cushion between the two halves. Say whether you want one piece or two — two is usual, because one will not come through the hatch.
- Quarter berth. Narrows towards the foot and usually has one curved side following the hull.
- Pilot berth. Long, narrow, shallow headroom above it. Depth matters more than anything else.
- Island bed. Nearly rectangular, usually with two radiused corners at the foot.
Get it through the hatch
Measure the companionway and the hatch before you order, not after. A 15 cm foam mattress will flex through a surprisingly small opening; a 20 cm latex one will not bend at all. If the opening is tight, a two-piece build with a zipped joining cover solves it and you will not feel the seam through a topper.
Damp is the whole problem
A boat mattress lives in a cold, humid, poorly ventilated box, often against a hull that is colder than the air. Moisture condenses on the underside and stays there. Without ventilation you will find mould on the base of the mattress inside one winter, and no mattress warranty in the industry covers it.
What actually works:
- A spacer mat under the mattress. A few millimetres of open mesh that lets air move. This is the single most effective thing you can do, and it costs less than the mattress cover.
- Open-cell fillings. Latex and natural fibres breathe; memory foam is the worst choice for a berth precisely because it is dense.
- Lift it when you leave. Stand the mattress on edge whenever the boat is unattended for more than a few days.
Depth and firmness afloat
Berths are shallow, so 10 to 15 cm is normal. Go slightly firmer than you would at home: a boat mattress usually sits on a solid GRP or ply base with no give at all, so the mattress is doing all the work and a soft build bottoms out.
Common questions
Can you work from a template I post?
A clear photograph with a tape in shot is enough for almost every berth. Get in touch before you post anything physical.
Will you make it in two pieces?
Yes, and for most V-berths we would recommend it.
Is it fire certified?
Yes — BS 7177 Low Hazard with a permanent Schedule 7 label, the same as every mattress we sell.