What Is Termowat (Thermobonded) Felt, and How Does It Differ from Standard Felt?

Felt is not a woven fabric. There is no warp and no weft: a web of loose fibres is consolidated into a single sheet. The raw material is predominantly reclaimed textile fibre, carded into a thin, evenly spread web before anything holds it together.

There are two ways to turn that web into a sheet. The first is mechanical: the web passes under a board of barbed needles that punch in and out repeatedly, dragging bundles of fibre up and down through the thickness until they lock into each other. That is needle-punched felt — no heat and no adhesive are involved.

The second is thermal: the web runs through a heated zone, some of the fibres soften and fuse where they touch, and the web is then cooled to set. The bond forms at the points where fibres cross — a weld rather than an entanglement. Termowat felt is made this way. In the Turkish market the same material also sells written termovat and thermowat; the spelling differs, the product does not.

One thing worth saying up front: YAYLA does not manufacture felt, it sources and supplies it. The site labels each of its four products as either made in-house or sourced — rebonded foam and pocket springs are manufactured, felt and roll foam are supplied. Saying so plainly makes clear which questions belong to a supply chain.

In needle-punched felt the bond is purely mechanical, which leaves the method free as to fibre type. The result is usually softer and drapes better: it wraps a profile, stretches over a frame or settles into a corner easily. The trade is the cut edge, which is left loose — with nothing holding the surface fibres, shedding along a cut is normal.

In Termowat felt the bond points give the sheet coherence in its own plane. It does not stretch as it comes off the roll, it holds the dimension it was cut to, and the cut edge stays clean, so no adhesive or tape is needed to stabilise it. Against that, the sheet is stiffer: where a tight fold or a narrow corner is wanted, it is less obliging than needle-punched felt.

So the question of which is better has no general answer. For a hidden interlayer trimmed in place, whose edge is never seen, needle-punched felt is more than adequate. For a panel cut to size, handled repeatedly along an assembly line and with a visible edge, working with Termowat means less waste and less correcting.

In a sprung mattress the layers run, from the bottom up, spring unit, felt, foam, quilted panel. Felt has two jobs in that order: it separates, and it spreads load.

Without it the foam rests directly on the coil ends. Those ends are not a continuous surface but discrete points of steel contact. Under load the foam is compressed locally over each point, pushed down into the gaps between them, and abraded against the wire over time. As the layer thins, the coil pattern starts to telegraph to the surface.

With felt in between, what the foam meets is a continuous plane rather than a field of points. A load pressing on one spot is passed up to the layer above spread across a wider area, and the foam is kept from being drawn into the coil cavities. That is the separator role, and it cannot be thought about apart from the load-spreading one.

The same reasoning applies over a pocket spring unit. There each coil sits in its own fabric pocket, so the top plane of the unit is a field of individual coil ends. A felt layer laid over it turns that field into the single continuous surface the foam can sit on.

The first thing to state is thickness. It directly affects how much the felt separates and how widely it spreads a load, and because it sets the height left for the layers above, it enters the total dimension of the build. Felt is supplied in various thicknesses; the figure that suits your application is best settled against the options on the product page.

The second is format: roll or sheet. If you have your own cutting line, roll is more flexible and feeds a continuous line better. If you are not cutting, sheet cut to size reduces both offcut and labour.

The third is roll width, and it is the one most often left out. If the width does not divide into the piece you cut, the remainder comes back as waste on every wrap. Stating your piece dimensions up front lets the width be chosen against them. If you are buying sheet, give finished length and width instead.

The fourth is quantity and the unit it is counted in: metres, rolls, sheets or pieces. Alongside it, say which type you want — standard needle-punched or Termowat. With those four together, a quotation can be settled in one round.