Boat Cushions for Canadian Lakes: Marine Vinyl, Dry-Fast Foam and Measuring

Quick answer: For open boats on Canadian lakes, choose a waterproof cover, either marine vinyl such as Sunbrella Horizon or Sunbrella Rain, with dry-fast foam so any water that gets in drains straight out. Sunbrella's marine collections are waterproof too, unlike most Sunbrella upholstery fabrics, which are water-repellent. Measure straight seats with a tape and make paper templates for curved bow seats, V-berths and sun pads.

From the Muskoka lakes and Georgian Bay to the Thousand Islands, Lake of the Woods and the Okanagan, Canadian boating seasons are short and busy. Boats get used hard from May to October, then hauled out, shrink-wrapped and put away. Cushions take spray, rain, wet swimsuits, sunscreen and full sun on open water, so the wrong materials show it quickly. Here is how to choose the fabric and foam, and how to measure so the new cushions fit.

Fabric: waterproof, or water-repellent?

This is the most important choice, and the words matter.

Marine vinyl (waterproof)

Marine vinyl, such as Sunbrella Horizon, is waterproof. Spray, rain and wet swimsuits stay on the surface and wipe off. It is the standard for open cockpit seats, bow seats, sun pads and anywhere that gets hosed down. It is also the easiest to keep clean of sunscreen and fish scales.

Sunbrella Rain (waterproof)

Sunbrella Rain is a waterproof woven fabric. It feels softer and cooler than vinyl on a hot day, while still keeping water out of the foam. It is a good middle ground for seats that get rained on but not sprayed constantly.

Sunbrella marine fabrics (waterproof)

Sunbrella's marine collections are waterproof, unlike most Sunbrella upholstery fabrics, which are water-repellent. They suit open seats, cabins, seating under a Bimini or hard top, and boathouses, where you want a woven fabric with the colour and fade resistance Sunbrella is known for.

Foam: dry-fast for open boats

Even with a waterproof cover, water finds its way in at the seams and zipper. Standard foam soaks it up and holds it, which leads to heavy, soggy cushions and mildew. Dry-fast foam has an open-cell structure that lets water run straight through, so the cushion drains and dries in hours. For any cushion on an open deck, dry-fast foam is the one to choose.

For cabin berths and covered seating that stays dry, regular seat foam is more supportive and works well. Our guide to cottage and dock cushions covers the same choices for the dock and boathouse.

How to measure boat cushions

Very few boat cushions are simple rectangles. Bow seats follow the curve of the hull, V-berths taper toward the bow and helm seats often have angled sides. Measure in inches with a metal tape, and use a template for anything curved.

Straight seats: cockpit benches and helm seats

1. Length: measure along the back of the seat base and again along the front edge.
2. Depth: measure from back to front at each end and in the middle.
3. Thickness: most boat seat cushions are 3″ to 4″. Check the height against the gunwale and console before you go thicker.

If the ends are angled, give us the back length, the front length and the depth, and we will cut the taper.

Curved seats and sun pads: make a template

1. Lay kraft paper or thin cardboard over the seat base and tape it in place.
2. Trace the outline with a marker, pressing into the corners.
3. Mark the top side, the edge that faces the bow, and where any cleats, cup holders, hatches or snaps sit.
4. Cut it out and test it on the seat.
5. Photograph the template flat with a tape measure in the shot, and note the thickness you want.

Custom shapes made from a template take 5–6 weeks, compared with 2–3 weeks for standard shapes.

V-berths

Measure the length down the centre line, the width at the head (the wide end) and the width at the foot (the narrow end). A berth split down the middle is easier to lift when you need to get into the storage underneath. Our guide to measuring in inches has more on tapered shapes and templates.

Ties, snaps and fixings

Matching fabric ties come standard and work well around rails and frames. Velcro is available on request. If your boat already has snaps, mark their positions on your template so the new cushions line up with the existing hardware.

Looking after boat cushions through the season

• After every trip: wipe vinyl with fresh water and a soft cloth, especially after sunscreen or a swim. Stand fabric cushions on edge to drain.
• Weekly: clean marine vinyl with mild soap and water and rinse well. Avoid harsh solvents, which can dry vinyl out.
• When the boat is covered: make sure cushions are dry before the cover goes on. Trapped moisture under a cover is the fastest way to grow mildew.

End of season: before the shrink-wrap

Take cushions off the boat before it is wrapped or stored for the winter. Clean them, dry them completely and store them indoors, off the floor, somewhere with air around them. Our guide to storing outdoor cushions over a Canadian winter walks through the routine. In spring, check each cushion before launch, and measure any that need replacing while the boat is still on the trailer and easy to reach.

Ready to order?

Build your cushions with the boat cushion builder in Sunbrella Horizon marine vinyl, or browse the waterproof Sunbrella collection. Every cushion is cut within ±0.5″ of your measurements or template, and if we miss that, we remake it free. Orders ship with free delivery across Canada, duties and GST/HST paid. Want new cushions for launch day? Order over the winter, especially for template shapes. Outfitting a marina, rental fleet or charter? See our marine bulk enquiry page.

Frequently asked questions

What is the best fabric for boat cushions?

For open seating, a waterproof cover: Sunbrella's marine collections, including marine vinyl such as Sunbrella Horizon, or Sunbrella Rain.

Is Sunbrella marine fabric waterproof?

Yes. Sunbrella's marine collections, including marine vinyl such as Sunbrella Horizon, are waterproof, unlike most Sunbrella upholstery fabrics, which are water-repellent.

What foam should I use in boat cushions?

Dry-fast foam for any cushion on an open deck. It drains water straight through and dries in hours. Regular seat foam suits dry cabin berths.

How do I measure a curved bow seat?

Make a paper template of the seat base, mark the top side and the bow edge, and photograph it with a tape measure in the shot. Template shapes take 5–6 weeks.

How thick should boat cushions be?

Most seat cushions are 3″ to 4″. Sun pads and berths are often thicker. Check the height against the gunwale and console first.