Custom Shape Cushion — Parallelogram, Angled & Irregular, Any Angle & Size

Old houses, attic rooms, and boat cockpits are rarely square. A bench under a sloped ceiling, a seat that follows a staircase, or a built-in that leans off-angle has four sides and not one right angle — so a rectangular cushion sits crooked and never fills the space.

A Custom Parallelogram Cushion — an angled, slanted, four-sided cushion — is built for exactly that. You give us all four edge lengths plus one diagonal, which locks the true shape, and we cut the foam and cover to match your angles.

Why customers choose us:

• Exact fit: four edges and a diagonal define the real shape, so the cushion matches an out-of-square, angled seat with no gaps
• Seat and back together: order matching pieces so the whole bench lines up
• Foam that lasts: choose the density for light seating or daily use
• YKK zipper covers: removable covers that unzip for easy cleaning
• Indoor or outdoor: upholstery fabric for an attic nook, marine-grade fabric for a boat cockpit

How to Measure a Parallelogram (Angled) Cushion

Measure all four edges: top, bottom, left, and right. Then measure one diagonal, from the bottom-left corner to the top-right corner. That diagonal is what locks a slanted four-sided shape, since four edges alone can still flex. Add the thickness you want. If the shape is unusual, trace it on kraft paper and send us the template.

You May Also Like:

• custom clipped-corner cushion
• custom hexagon bay window cushion
• custom bench cushion

A Custom Quadrilateral Cushion is a four-sided cushion where none of the corners are square. It fits the out-of-square seats that show up in older homes, attics, and boats, where every edge is a different length. You give us the four edges and one diagonal, and we cut the exact shape.

Perfect for:

• Attic and knee wall benches, where the sloped ceiling leaves no square corner
• Under-stair bench cushions cut to the angle of the staircase
• Sloped ceiling window seats in bedrooms and lofts
• Boat cockpit cushions and other marine seats with irregular angles
• RV slide-out cushions where the seat meets the wall on a slant
• Any built-in bench in an old house where the walls are out of square

Order it as a seat, a back, or both. Send the four edges and the diagonal, and we cut the foam to fit the first time.

This cushion fits any four-sided seat where the corners are not square, including parallelograms, trapezoids, and fully irregular shapes. If a rectangle sits crooked in your seat or leaves a wedge-shaped gap along one edge, a quadrilateral cushion is what you need. To confirm the fit, measure all four edges and one diagonal from the bottom-left corner to the top-right corner, then send those five numbers. It can be made as a seat, a back, or both, indoors or outdoors depending on the fabric.

A quadrilateral cushion turns up in attics, lofts, and boats, so the fabric catalogue spans indoor and marine. The right cloth depends on where the seat lives.

All fabrics are:

• Fade and UV resistant, for lofts and boats that get strong, direct light
• Easy to wipe clean, for high-traffic under-stair and entry benches
• Moisture and mildew resistant, which matters on boats and in damp basements
• Built to take daily sitting without thinning at the angled edges
• Offered in a wide range of solids and patterns to match any room

For a boat cockpit or open-air seat, choose solution-dyed acrylic or marine-grade fabric. For an indoor attic or under-stair nook, soft upholstery weaves give a warmer, tailored look.