Seat cushion constructions compared: foam, wrap, feather and spring

At a glance

A qualitative comparison from trade practice and our published pages, to be confirmed by the partner upholsterer for the builds they make. Foam density and hardness are on the foam sheet. No fire pass level is stated here: the Responsible Person sets the hazard category.

Five builds in section

The drawing shows the five builds as a box cushion cut vertically. The differences are in what sits between the cover and the core:

• 1 Foam only. One block, or a few layers of different grades. Nothing to shift, so nothing to plump. It reads crisp, even with a softer top layer, which is why it is the usual choice where the seat has to look the same all day.
• 2 Foam with fibre wrap. A polyester fibre layer around the foam softens the edge and the first touch without any feather. The fibre settles with use, so it is lifted and turned now and then.
• 3 Foam with feather wrap. A feather and down layer, held in chambers inside a down-proof inner case, sits around a foam core. The foam keeps the shape between dressings and the wrap gives the soft, slightly crushed look. It needs plumping.
• 4 Feather and down fill. No core: the whole cushion is fill in chambers. It is the softest and sinks deepest, and it depends most on being dressed. Back cushions are often built this way because they carry no weight.
• 5 Spring interior. A unit of pocket springs sits between foam layers, with a wrap over the top and round the sides. The springs add give and resilience; the surface feel comes from the layers above them. This is a cushion core, not the seat suspension under the cushion: see seat suspension systems compared.

A chambered casing matters in 3 and 4: it is stitched into compartments so that the fill cannot slump to one end. How the fill is labelled and the ticking that holds it are on feather and down in upholstery.

Choosing by use

No build is best for everything. The table is our reading of where each build is put forward first; the partner upholsterer confirms it for the pieces they make, and the hazard category the Responsible Person has set for the premises comes first. It matches the position on our upholstery fills page: solid foam for the hardest-worked seating, wrapped builds where someone will dress them.

The feel is only part of the answer. Seat geometry, suspension and cover tightness change how a seat sits as much as the fill does, which is why the formal versus relaxed matrix sets them together. For private use the choice is largely taste and willingness to plump; for contract use it is duty, housekeeping and the fire certificate.

Fire: what has to sit inside the tested build

The FIRA and British Furniture Confederation guide (2010, updated 2011) says that each different upholstery composite, the combination of cover and filling in an item of upholstered seating, must satisfy the ignition requirements, and that a seat, back and arms with different fillings are separate composites. It also says that BS 7176 requires filling materials in every hazard category to satisfy the ignition tests in its annexes separately (urethane foam must satisfy Annex A).

That is why the build matters. A fabric supplier's certificate usually comes from testing over a 35 kg/m3 combustion modified foam, and the guide says the behaviour of "distinctly different filling types is difficult to equate" and that testing the actual fabric and filling composites is advised. The guide does not name feather or fibre wraps. Our reading is that builds 3, 4 and 5 are such cases, and 2 may be: ask the test house, and do not assume a certificate for a foam-only seat carries over to a wrapped one.

• Ask for the certificate for the build as supplied, naming every layer: cover, interliner, wrap, ticking and foam.
• Treat any change as a new model: the guide says a change of filling or of component supplier needs re-testing, and that enforcement authorities normally expect a UKAS accredited test certificate less than a year old.
• Do not match a build to a hazard category here. The Responsible Person sets it, and the project's fire consultant says what it needs: see BS 7176 hazard categories and the fire documentation matrix.

What to ask the workshop to put in writing

• A build-up drawing for the seat and back cushions with every layer named and its thickness stated: cover, interliner, ticking, wrap, each foam and, for build 5, the spring unit.
• For a wrap or fill, the material and its declaration: fibre type, or feather and down composition (see the feather and down sheet).
• The foam grade, measured density with tolerance and hardness with method for each foam layer, as on the foam sheet.
• The composite fire certificate for the build as supplied, from a UKAS accredited laboratory, dated within a year, for the hazard category set for the premises.
• A care and plumping routine for the build, and who will carry it out.
• Whether the cushion can be refilled or re-cased without replacing the foam.
• A full-size mock-up approved by sit test before production.

Seat cushion: [foam only]. Foam [grade] [ ] mm thick, density [ ] kg/m3 (ISO 845), hardness [ ] N at [40] % indentation (ISO 2439, method [ ]). Cover [ ], interliner [as the fire certificate requires]. Foam data sheet, foam ignition certificate and a composite certificate for the build as supplied to be provided with the shop drawings.

Seat cushion: foam core [grade] [ ] mm with [polyester fibre] wrap [ ] mm thick on the top and sides, cover [ ], interliner [as the fire certificate requires]. Wrap and interliner to be inside the tested composite. Composite certificate for the build as supplied.

Seat cushion: foam core [grade] [ ] mm with a feather and down wrap [ ] mm thick in chambered down-proof ticking, composition [ ] % feather, [ ] % down by weight, declared to [EN 12934:2025]. Composite certificate for the build as supplied, not a foam-only certificate. Plumping instructions to be supplied.

Seat cushion: feather and down fill, no core, [ ] % feather, [ ] % down by weight declared to [EN 12934:2025], [ ] g per cushion, in down-proof ticking with [ ] chambers. Composite certificate for the build as supplied. Plumping and turning routine to be supplied.

Seat cushion: spring interior. Pocket-spring unit [ ] mm high between foam layers [ ] mm above and [ ] mm below, wrapped in [fibre / feather and down], cover [ ]. Supplier to state the spring unit and its base support. Composite certificate for the build as supplied.

Standards and sources

• FIRA and the British Furniture Confederation, Fire safety of furniture and furnishings in the contract and non-domestic sectors (2010, updated 2011): composites, filling annexes, re-testing; the guide does not name feather or fibre wraps.
• BS EN 12934:2025: feather and down composition labelling; contents list and foreword read in a free preview, clauses not read.
• BS 7176 and BS 5852: as described in the FIRA guide; not read. Confirm against the current editions.
• Make Bespoke Studio: upholstery fills and technical sheets: the fill families and care notes this sheet compares.

Questions we are asked

What is the difference between a feather-wrapped foam cushion and an all-feather cushion?

A feather-wrapped cushion has a foam core with a feather and down layer around it, so the foam keeps the shape and the wrap gives the soft surface. An all-feather cushion is fill in chambers with no core: softer, and dependent on daily plumping.

Which seat cushion construction suits a restaurant or hotel?

There is no single answer. For heavy daily use, foam alone or foam with a thin fibre wrap holds its shape without a plumping routine, which is why we put those forward first. Wrapped builds suit seats that someone will dress. The hazard category set for the premises and the certificate for the exact build come first.

Does a feather-filled cushion meet the fire requirements?

It can be tested like any other build, but a certificate applies to the composite that was tested. The FIRA guide advises testing the actual composite for distinctly different filling types, so do not assume a foam-only certificate carries over. The Responsible Person sets the hazard category for the premises.

What is a spring-interior cushion?

A cushion with a pocket-spring unit as its core, between foam layers and under a wrap. The springs add give and resilience. It is separate from the seat suspension under the cushion, such as eight-way hand-tied or sinuous springs.

How often do feather and down cushions need plumping?

Our fills guide says daily on primary seating and every few weeks for turning the casing, with a foam-cored wrap needing less. For contract seating, agree the routine and who carries it out with the workshop and housekeeping before you choose the build.

Can a feather cushion be refilled?

Often, yes: a cushion can be re-filled or re-cased rather than replaced, as our fills guide says. Whether a specific build can be depends on its construction, so ask the workshop.