---
title: "Large Bay Window Cushions: Where to Split a Seat Over 9 Feet"
url: "https://cushionguide.com/concepts/large-bay-window-cushions/"
section: "Concept Sketches"
author: "Nate Kowalski, The Pattern Engineer of Detroit"
author_url: "https://cushionguide.com/masters/nate/"
published: "2026-08-28"
updated: "2026-09-24"
keywords: "large bay window cushion, bay window seat cushion in two pieces, long window seat cushion, trapezoid bay window cushion, split window seat cushion, custom bay window cushion, vacuum packed cushion recovery"
---

# Big bays, long seats: where to split a large bay window cushion

*Eight of the biggest bays from past orders, ranging from a 107.5 in back edge to a 14 ft 10.5 in bottom run: where one piece still works, where the seam lands, and why nobody measures a long cushion on day one.*

> **The quick answer:** A large bay window cushion longer than about 7.5 ft (2.3 m) is usually best made in two or more pieces, joined at a bay corner or at the midpoint. Pieces are easier to make, ship, lift out and clean. One piece is still possible on request. Measure every edge separately, and give a vacuum-packed cushion 48-72 hours to recover before checking its size.

![Charcoal textured box cushion with light gray piping on a white drawer window seat facing a clipped garden, marble side table](https://cushionguide.com/media/window-seat-cushions/charcoal-window-seat-cushion-light-gray-piping-garden-1536.webp "Pale gray piping outlines a charcoal cushion like a pencil line, keeping a dark seat crisp against white cabinetry.")

## Past 7.5 feet, the seam becomes the design

The longest bay in this series runs 14 ft 10.5 in (453 cm) along its bottom edge. Nobody should have to carry that as one cushion.

Past about 7.5 ft (2.3 m), a single **large bay window cushion** gets hard to make, ship and lift out for cleaning. For trapezoids around 6.5 ft (2 m) or more on the long side, the workshop may suggest two pieces; for straight seats of roughly 8 to 10 ft (2.5 to 3 m), it recommends equal pieces.

So the working question is where the seam lands: at a bay corner, where each piece follows one run of the angle, or at the midpoint, where a straight seat splits into twins. Angles are just lengths in disguise.

Eight big bays from past orders follow, sizes kept exact. Run yours through the [bay window calculator](https://cushionguide.com/studio/bay-window-calculator/) or the [trapezoid cushion calculator](https://cushionguide.com/studio/trapezoid-cushion-calculator/), and browse the [bay window cushions](https://cushionguide.com/cushions/bay-window-cushions/) and [trapezoid cushions](https://cushionguide.com/cushions/trapezoid-cushions/) hubs. What does your longest edge measure, partner?

## Eight big bays and where each one split

### 01. 14 ft 10.5 in of trapezoid, split where the bay turns

![Navy corduroy box cushion on a cream plinth under a large picture window, with oak cube shelves and terracotta floor](https://cushionguide.com/media/window-seat-cushions/navy-corduroy-plinth-seat-picture-window-1600.webp "A dark, low seat that frames a picture window; the view above is left completely clear.")

One buyer wrote in with a trapezoid bay 8 ft 7 in (262 cm) along the top, 14 ft 10.5 in (453 cm) along the bottom and 29 in (74 cm) deep, with 2 ft 6 in (76 cm) sides and angled corners of 11 in (28 cm) and 5.5 in (14 cm), in 5 in (13 cm) linen. The workshop recommended two pieces, joined at a corner or the midpoint, and asked for a sketch or photo to confirm the angles.

**The takeaway:** A corner seam lets each piece follow one run of the bay; a midpoint seam gives two pieces closer in size.

> **Tailor's margin:** A 14 ft 10.5 in trapezoid bay cushion goes in two pieces, joined at a corner or the midpoint.

### 02. 154 5/16 in, kept in one piece on purpose

![Cream and black zebra-stripe window seat cushion on shaker kitchen drawers with black cup handles under a white window](https://cushionguide.com/media/window-seat-cushions/zebra-window-seat-cushion-shaker-kitchen-drawers-1600.webp "Kitchen base units become a window seat, and the zebra cushion softens a run of cream cabinetry.")

A buyer in the US asked whether a wide angled seat could be one piece, in a wipe-clean fabric. The lettered drawing gave a 154 5/16 in (392 cm) front, a 108 in (274 cm) back and only 15 in (38 cm) of depth. The workshop drew a template from those letters, confirmed the one-piece build and suggested velvet.

**The takeaway:** One piece stays an option on request; have the template drawn and confirmed before you order it.

> **Tailor's margin:** A 154 5/16 in angled window seat cushion was confirmed as one piece from a lettered template.

### 03. About 160 in of black, sun-resistant cloth

![Deep ivory window seat cushion with near-black pinstripes, an oatmeal pillow, sheer curtains and a pothos in a cream urn](https://cushionguide.com/media/window-seat-cushions/deep-pinstripe-window-seat-pothos-sheer-curtains-1600.webp "A tall, crisp box edge lets the pinstripe show on the front face, while sheers and a trailing pothos keep the corner soft.")

A buyer in the US wanted a trapezoid bay cushion about 160 x 24 in (406 x 61 cm) in a black, sun-resistant fabric, and specifically not corduroy or velvet. The workshop confirmed sun-resistant fabrics are in stock and suggested two pieces because of the length.

**The takeaway:** Choose the cloth for the sun and the split for the length.

> **Tailor's margin:** A 160 x 24 in bay window cushion is easier to make and handle as two sections than as one.

### 04. A 14 ft nook, still being framed

![Light gray corduroy cushion on a cream paneled window seat against a navy wall, with a walnut desk and rush chair](https://cushionguide.com/media/window-seat-cushions/gray-corduroy-window-seat-navy-wall-walnut-desk-1600.webp "Pale gray corduroy lifts a navy study and gives the desk a softer neighbor for reading breaks.")

A family in the US was still building their window nook: 14 ft (4.3 m) wide in total and 36 in (91 cm) deep, with cushions in smoke. They were happy to split the run, so the full length was quoted as several sections that butt together.

**The takeaway:** Settle the section count while the nook is open; send final sizes from the finished build.

> **Tailor's margin:** A 14 ft window nook 36 in deep is made as several cushion sections that butt together.

### 05. 154.5 in, halved into 77.25 in twins

![Anthracite corduroy box cushion on a white built-in window seat in a blush pink room with an oak side table and fern](https://cushionguide.com/media/window-seat-cushions/anthracite-corduroy-window-seat-blush-room-1600.webp "Charcoal against blush: the dark cushion keeps a pink room from feeling too soft.")

A buyer in the US had a straight 154.5 x 22 in (392 x 56 cm) window seat and wanted corduroy. It became two identical 77.25 x 22 in (196 x 56 cm) cushions, ordered through the closest menu size with the exact size in the personalization box. They fit, but the knife that opened the tight shrink-wrap also cut the covers; the workshop offered replacements, and the buyer later came back for other benches.

**The takeaway:** On a straight seat, a midpoint split gives identical halves: one size, written twice.

> **Tailor's margin:** Open vacuum-packed cushions by cutting only the outer plastic; a blade that goes deeper cuts the cover too.

### 06. About 9 ft wide, four thicknesses on offer

![Front view of a mustard corduroy box cushion with self piping on top and bottom edges, a navy pillow leaning on the wall](https://cushionguide.com/media/window-seat-cushions/mustard-corduroy-cushion-double-piping-front-detail-1600.webp "Straight on, the cushion shows piping on both the top and bottom seams and a ribbed side panel. A navy linen pillow leans into the reveal as a backrest.")

A buyer messaged the workshop with a bay about 9 ft (2.7 m) wide: 107.5 in (273 cm) back, 55 in (140 cm) front, two 32.5 in (83 cm) sides, 23 in (58 cm) deep. Priced as a custom shape, it could be 2, 3, 4 or 5 in (5 to 13 cm) thick, with piping in any color and a removable cover washable at 86°F (30°C), no dryer. The quote came in above their budget.

**The takeaway:** Get the custom-shape quote before you design the room around one big piece.

> **Tailor's margin:** A 107.5 in bay cushion can be 2, 3, 4 or 5 in thick, cover washable at 86°F (30°C).

### 07. 2.5 in short on arrival, full size two days later

![Dusty rose woven box cushion on a cream paneled storage chest beneath an arched window, olive tree and faded pink rug](https://cushionguide.com/media/window-seat-cushions/dusty-rose-cushion-paneled-chest-arched-window-1600.webp "A slim dusty rose cushion dresses a paneled chest beneath an arched window. The rug's faded pink makes the color choice feel inevitable.")

A buyer messaged the workshop about a wide bay: 95 in (241 cm) front, 47.5 in (121 cm) back, 34 in (86 cm) angled ends, 24 in (61 cm) deep, 3 in (7.6 cm) thick. After a lettered template and one corrected edge, the geometry added up. The cushion arrived at 92.5 in (235 cm) and reached full size after 48 hours of foam recovery, no remake.

**The takeaway:** Give a vacuum-packed cushion 48-72 hours before the tape measure comes out; long pieces recover by inches.

> **Tailor's margin:** A vacuum-packed 95 in bay cushion measured 92.5 in on arrival and reached full size after 48 hours.

### 08. Left 33.75 in, right 33 in, both correct

![Dusty blue bouclé window seat cushion on a cream paneled storage box beside leaded windows, with a book and mug](https://cushionguide.com/media/window-seat-cushions/dusty-blue-boucle-window-seat-leaded-glass-928.webp "Dusty blue bouclé brings gentle color to a cream window seat framed by old leaded glass.")

A buyer in the US sent four numbers for an angled bay: 68.25 in (173 cm) at the back against the wall, 113.75 in (289 cm) at the front, 33.75 in (86 cm) on the left and 33 in (84 cm) on the right. The sides differ by 3/4 in (2 cm), which is normal for real walls, and the workshop quoted it as a custom shape.

**The takeaway:** Measure both slants separately, even when you expect them to match.

> **Tailor's margin:** On a trapezoid window seat, the left and right sides are rarely identical; measure and label each one.

## One piece, twins or segments: choosing the split for a long cushion

Pick the build first, then draw each piece. [One piece or two](https://cushionguide.com/guides/long-bench-cushion-one-piece-or-two/) covers straight benches, [trapezoid cushion measurements](https://cushionguide.com/guides/trapezoid-cushion-measurements/) covers angles, and [Victorian bay window seat cushions](https://cushionguide.com/concepts/victorian-bay-window-seat-cushions/) is the sister series. Fabric comes last: the 14 ft bay chose [linen](https://cushionguide.com/fabrics/linen-and-cotton-linen/), the twins [corduroy](https://cushionguide.com/fabrics/corduroy/).

| Build | Where the seam lands | Fits best | from past orders |
|---|---|---|---|
| One piece | Nowhere | Any length, on request, once the template is confirmed | 154 5/16 x 15 in (392 x 38 cm) angled seat; a 103.5 in (263 cm) cushion |
| Identical halves | The midpoint | Straight runs, where both pieces share one size | 154.5 x 22 in seat as two 77.25 x 22 in (196 x 56 cm) cushions |
| Segments that follow the angles | A bay corner | Trapezoids and three-sided bays | 14 ft 10.5 in trapezoid, joined at a corner or the midpoint |
| Several butting sections | Wherever you choose | Very wide nooks | 14 ft x 36 in (4.3 m x 91 cm) nook; a 197 in (500 cm) nook in three pieces |
| Two over a radiator | The midpoint | Ledges above a radiator, so heat escapes | 106 x 15 in (269 x 38 cm) ledge as two 53 x 15 in (135 x 38 cm) cushions |

## Unpacking a long cushion: the first 72 hours

1. Unpack within a few days. Foam shouldn't stay vacuum-packed more than 2-3 weeks, never more than a month.
2. Cut only the outer plastic, blade shallow and pointed away from the cover.
3. Take the cover off; shake, pull, knead or stretch the foam.
4. Sit on the cushion if you like; it can be used while it finishes expanding.
5. Measure at 48-72 hours, edge by edge against your drawing.

> A bay window cushion longer than about 7.5 ft (2.3 m) is easier to make, ship and lift out as two pieces, joined at a corner or the midpoint.
>
> — Nate

## Long-seat and bay questions

**A common question:** My window seat is really long. Should the cushion be one piece or split into sections?

**The workshop's answer:** For seats around 8 to 10 ft (2.5-3 m) and longer, the workshop recommends equal pieces: they fit better, last longer and are easier to handle. A 92 in (234 cm) seat was suggested as two 46 in (117 cm) cushions, and a 197 in (500 cm) nook was made in three pieces. Each piece is ordered at its own size, usually by adding two or more cushions to the cart. Long soft back pillows sag, so an 88 in back works better as two 44 in pillows. It's still your call: one piece can be made on request, and a photo with measurements gets you the workshop's advice.

**A common question:** What exactly do you need me to measure on a trapezoid bay seat?

**The workshop's answer:** Every edge: the front, the back along the window, both angled sides, any small clipped corners or short straight ends, plus the depth and thickness. Measure the depth straight from the highest point down to the base line, and measure each angled side on its own, corner to corner, because those sides are not the same as the depth. Mark every break in the bay and any cut-out, such as a window handle, and send a labeled drawing (A, B, C, D) with a photo of the space. If a side is missing, the workshop asks for it before quoting, and very long trapezoids may come back with a two-piece suggestion.

**A common question:** Can I order my angled bay seat cushion on the regular rectangle listing?

**The workshop's answer:** No. Angled and three-sided bays go on the custom-shape (trapezoid) listing. Choose the size by the depth and overall length, then upload a drawing with every edge, any cut-ins and the depth, plus a photo of the seat; a hand sketch on paper is enough. Asymmetric bays can be sketched or traced onto a paper template, and the workshop may ask for a few extra measurements before quoting. When an angled shape landed on the rectangle listing in past orders, it was canceled and refunded so the buyer could reorder on the right one.

**A common question:** Can you really make a cushion to my exact size, even something longer than 79 in?

**The workshop's answer:** Yes. Every cushion is made to order, so any length, width and thickness can be made, including lengths over 79 in (200 cm), and inches, centimeters or millimeters are all accepted. Send the length, depth and thickness, plus a drawing for anything that isn't a rectangle, and the workshop replies with a quote. You then pick the nearest listed size and write your exact size in the personalization note, or the workshop adds your size to the listing or sends a private custom order link. Trapezoids go through the custom-shape listing, with the longest edge as the length.

## Questions buyers ask next

### How long should I wait before measuring a vacuum-packed bay cushion?

Wait 48 to 72 hours. One 95 in (241 cm) bay cushion measured 92.5 in (235 cm) on arrival and reached full size after 48 hours, no remake needed. Unpack within a few days, take the cover off and knead the foam. The [first 72 hours](https://cushionguide.com/guides/vacuum-packed-cushion-first-72-hours/) Pattern has the full routine, and the glossary explains [foam recovery](https://cushionguide.com/glossary/#foam-recovery).

### Why are the left and right sides of my bay seat different lengths?

Because real walls are rarely square. One buyer in the US measured 33.75 in (86 cm) on the left and 33 in (84 cm) on the right of the same bay, which is normal. Measure and label each slant separately rather than repeating one number; the cushion is cut to your drawing, not to an assumed symmetry.

### What if my angled side doesn't match what the math says it should be?

Re-measure before anything is cut. If a measured slant and a calculated slant differ by more than about 1 in (2.5 cm), one number is off. On one US bay the drawing said 31 in slants and the math said 32.5 in; a re-measure confirmed 32.5 in, and the cushion went ahead at 4 in (10 cm) thick. See [tolerance](https://cushionguide.com/glossary/#tolerance).

### If I split a bay cushion, do I order the pieces separately?

Yes. Each piece is its own cart item at its own size. Rectangular pieces go on the normal listing, and each angled piece goes on the custom-shape listing with its own drawing, since every distinct shape is a separate order. You can ask for photos of the finished pieces, with measurements, before they ship.

## Related at the atelier

- [Bay Window Cushion in Flax Linen: Wine Piping in Changing Light](https://cushionguide.com/readings/flax-bay-window-cushion-wine-piping-striped-lumbar/): Check a bay window cushion fabric in the bay itself at three times of day, because a three-panel bay lights the seat from several directions and the color shifts with them.
- [Craftsman window seat cushions for shallow bays and short returns](https://cushionguide.com/concepts/craftsman-bungalow-window-seat-cushions/): A craftsman window seat cushion is usually a clipped trapezoid: a long front edge, a shorter back edge, and a short straight return at each end before the angled sides begin.
- [My window seat has lift-up lids. Should the cushion be split?](https://cushionguide.com/answers/storage-bench-lift-up-lid-cushion-sections/): Yes: split a storage bench cushion at the lid lines, so each section lifts with its own lid; three lids get three cushions.
- [5-sided bay window cushions: working out angles, sections and seams](https://cushionguide.com/guides/5-sided-bay-window-cushion-calculator/): Measure a 5-sided bay window cushion edge by edge: every back segment, the short end returns, the front and the depth at each break, each with its own letter.
- [Bay Window Cushion in Olive with Ivory Piping over a Radiator](https://cushionguide.com/readings/olive-trapezoid-bay-cushion-over-radiator-sitting-room/): Contrast piping is the right call on a bay window cushion when the fabric sits close in tone to the wall behind it.
- [Bay Window Cushion in Olive Gold Velvet: The Daily-Life Test](https://cushionguide.com/readings/olive-gold-velvet-trapezoid-dining-bay-seat/): A velvet bay window cushion beside a dining table ages well when it is specified for daily loads.
- [Measuring a 3-sided bay window seat cushion, panel by panel](https://cushionguide.com/guides/bay-window-seat-cushion-3-sided/)

*± 1/4 in — Nate*

---

Written by Nate Kowalski (https://cushionguide.com/masters/nate/) for CushionGuide (https://cushionguide.com/about/). The site explains made-to-measure cushions and the partner workshop makes them; measurements are in inches first. This Markdown mirrors the page at https://cushionguide.com/concepts/large-bay-window-cushions/