---
title: "Back Cushion Filling: Shredded Foam Backs, Solid Foam Seats"
url: "https://cushionguide.com/answers/back-cushion-filling-shredded-vs-solid-foam/"
section: "The Cutting Table"
author: "Hana Lindqvist, The Quiet Geometer of Seattle"
author_url: "https://cushionguide.com/masters/hana/"
published: "2026-09-04"
updated: "2026-09-04"
keywords: "back cushion filling, shredded foam back cushions, backrest cushion foam, solid foam vs shredded foam, back pillow thickness"
---

# Are the back cushions the same foam as the seat?

*They are not. The seat holds you up. The back receives you. Two jobs, two fillings.*

Also asked as: Different foam for the back cushion?; Solid foam or shredded for the backrest?

> **The quick answer:** Back cushions are not the same foam as the seat: seats are firm solid foam at 32 density (32 kg/m³, about 2.0 lb/ft³), while back pillows are usually shredded foam or fiber, softer to lean on. Filled back pillows come out about 4-6 in (10-15 cm) thick, so you give only width and height. A solid-foam backrest is available if you prefer.

![Close-up of a black and cream geometric jacquard back cushion resting on a terracotta bouclé seat cushion by arched windows](https://cushionguide.com/media/backrest-cushions/geometric-backrest-terracotta-boucle-seat-closeup-1600.webp "Two fabrics, one seat: a crisp geometric back cushion lifts a warm terracotta bouclé base.")

## Key facts

- Seat cushions use firm solid foam at 32 density (32 kg/m³, about 2.0 lb/ft³).
- Back pillows are filled with shredded foam or fiber for a softer lean.
- The shredded foam is broken into small pieces on the shop's own machine.
- Filled back pillows come out about 4-6 in (10-15 cm) thick; only width and height are needed.
- A solid-foam backrest is available, and the shop confirms the filling before production.
- The filling is a separate insert; the zippered cover washes at 86°F (30°C) on a gentle cycle.

## Seat and back pillow, side by side

| Detail | Seat cushion | Back pillow |
|---|---|---|
| Filling | Solid foam, 32 density (about 2.0 lb/ft³) | Shredded foam or fiber |
| Feel | Firm, holds its shape under weight | Soft and pillow-like, still holds against a rail |
| Thickness | The number you order | About 4-6 in (10-15 cm), set by the fill |
| What you measure | Width, depth and thickness | Width and height only |
| Other option | Stays high-density foam | Solid foam like the seat, on request |

## Why the back gets the softer fill

A seat carries your weight for hours. It needs a solid block that stays level. That is the work of the 32-density foam.

A back does something gentler. You lean, shift, lean again. [Shredded foam](https://cushionguide.com/glossary/#shredded-foam), broken into small pieces on the shop's own machine, lets the pillow shape itself around you and still hold its form against a rail. Fiber does the same, a little softer.

Because a filled pillow has no fixed thickness, you do not choose one. It comes out about 4-6 in (10-15 cm) deep. Give width and height and let the fill decide the rest. The [back cushion fill Pattern](https://cushionguide.com/guides/back-cushion-fill-shredded-foam-vs-wedge/) sets this beside a solid wedge, and the [backrest cushions](https://cushionguide.com/cushions/backrest-cushions/) page shows the shapes.

## What to send for a backrest

- ✓ Width and height of each back pillow.
- ✓ The seat cushion size and thickness, listed separately.
- ✓ Your filling choice: shredded foam, fiber, or solid foam like the seat.
- ✓ A reply to the shop's filling check before production starts.

## Nothing is sewn shut

The filling sits in its own insert. The cover closes with a zipper and comes off for washing at 86°F (30°C) on a gentle cycle. On a [banquette](https://cushionguide.com/cushions/banquette-cushions/) where coffee and elbows meet, that matters more than any foam number.

Which do you use more, the back or the seat?

The seat holds.
The back receives.
Each gets the filling for its job.

> **Tailor's margin:** Back cushion filling is usually shredded foam, not the seat's solid 32-density block, so a filled back pillow lands about 4-6 in thick.

> Order back pillows by width and height only; a shredded-foam filling sets the thickness at about 4-6 in (10-15 cm).
>
> — Hana

## Buyer questions

**A common question:** Should my backrest be solid foam like the seat, or something softer?

**The workshop's answer:** Either works. The backrest can be solid foam like the seat cushion, or filled with shredded foam, which is softer and more pillow-like. Throw pillows get the same shredded foam for a soft, plump feel.

**A common question:** Is the back cushion cut from the seat foam, and how thick will it be?

**The workshop's answer:** No. The seat uses firm 32-density foam; back cushions are shredded foam or fiber, softer to lean on. As filled pillows they have no fixed thickness and come out roughly 4-6 in (10-15 cm), so only width and height are needed.

**A common question:** What filling would you put in the back cushions of a banquette?

**The workshop's answer:** Shredded foam, which is softer than the solid foam used in the seats. The seat cushions stay high-density foam.

**A common question:** What's inside the back pillows, and can the covers come off to be washed?

**The workshop's answer:** Shredded foam, broken into small pieces on the shop's own machine: soft, but supportive enough to hold its shape against a pillow rail. The filling is a separate insert and the cover zips off for washing at 86°F (30°C) on a gentle cycle. Nothing is sewn shut.

**A common question:** Can I buy only the foam inserts, without covers?

**The workshop's answer:** Yes. Pillow fillings, foam-only L-shaped backrest inserts and full sofa foam sets are sold without covers through a dedicated link, quoted per set.

## Questions buyers ask next

### Do shredded foam back pillows get lumpy?

The pieces can shift with use. A lump usually means the filling has moved, and it can be worked back into shape by hand through the cover. That flexibility is why backrests use pieces instead of one rigid block.

### Who decides the backrest filling on a custom order?

You choose, and the shop checks. Shredded foam is the usual pick, solid foam like the seat is available, and the workshop confirms the backrest filling with you before production so nothing is assumed.

### How firm is 32-density seat foam in US terms?

32 kg/m³ is about 2.0 lb/ft³, a solid everyday seat foam. Density speaks to durability more than softness, which is why the seat stays firm while the back pillows are left softer on purpose.

## Related at the atelier

- [Back cushion filling compared: shredded foam, a solid wedge or fiber](https://cushionguide.com/guides/back-cushion-fill-shredded-foam-vs-wedge/): For most benches and banquettes, a shredded-foam back pillow over a firm foam seat is the right default: soft to lean on, yet it keeps its shape against a wall.
- [For a bolster or a very thick backrest, should I choose foam or silicone ball fill?](https://cushionguide.com/answers/bolster-thick-backrest-foam-vs-fiber-fill/): Choose foam for a non-tufted backrest 12-14 in (30-35 cm) thick, often cut as a wedge, and silicone ball fill for round arm bolsters, because silicone balls can't hold a backrest that thick.
- [Can I buy just the foam inserts, without the covers?](https://cushionguide.com/answers/buy-foam-inserts-without-covers/): Yes, foam inserts and fillings are sold on their own, without covers.
- [Can the back cushion be thinner than the seat cushion?](https://cushionguide.com/answers/back-cushion-thinner-than-seat-cushion-2/): Yes, a back cushion can be thinner than its seat cushion when you order each cushion separately and write its thickness in personalization: a 4 in (10 cm) seat with a 2 or 3 in (5 or 7.5 cm) back is…
- [Bench Seat and Back Cushion in Jacquard and Terracotta Bouclé](https://cushionguide.com/readings/geometric-backrest-terracotta-boucle-seat-closeup/): For a bench seat and back cushion in two fabrics, put the forgiving cloth on the seat and the pattern on the back.
- [How to keep back cushions upright on benches and banquettes](https://cushionguide.com/guides/back-cushions-staying-upright/): To keep back cushions in place, match the fix to what's behind them: ties for slats or a rail, a non-slip backing for a flat wall, a wedge shape for a lean.
- [How tall should a back cushion be? Sizing backrests to your seat](https://cushionguide.com/guides/back-cushion-height-sizing/)

*— Hana*

---

Written by Hana Lindqvist (https://cushionguide.com/masters/hana/) 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/answers/back-cushion-filling-shredded-vs-solid-foam/