Custom-size mattress: how to measure your bed and get it right

A custom-size mattress is made to the inside dimensions of the bed — the space it will actually lie in — not to the outside of the frame. Measure at several points and take the smallest value. Our factory's mattress care rules prohibit using a mattress that is more than 1.5 cm larger than the inside of the bed in length or width — and they warn that a mattress that is too small also deforms. A custom size adds 1–2 days to the usual production time of 3–5 working days.

Below is how to measure so that the mattress fits the first time, and what to check in the bed before you order.

When a standard size will not fit

We make eight standard sizes: 80×200, 90×200, 100×200, 120×200, 140×200, 160×200, 180×200 and 200×200. A custom size is needed if your bed matches none of them. Most often that means:

• a bed 190 cm long — a 200 cm mattress simply will not go in;
• a made-to-order bed or one built to an old design, with a width between the standard sizes;
• a bed with an unusual headboard or footboard that takes up part of the length.

If you are not sure whether your bed is standard, measure it first using the steps below. It often turns out that a bed that is "160 by eye" is actually 155 or 158, and a standard mattress would sit badly in it.

How to measure correctly

Measure the inside, not the frame. You need the size of the space the mattress lies in: from the inner side of one rail to the inner side of the other. The outside dimensions of the bed mean nothing for the mattress.

Measure at three points. Length along the left edge, the centre and the right edge. Width at the head, the middle and the foot. Frames are almost never perfect rectangles, and a difference of a centimetre between points is normal.

Take the smallest measurement. If the width at three points is 158, 159 and 158.5 cm, the order goes in at 158. A mattress made to the larger value will press against the frame at its narrowest point.

Use a metal tape measure, not a tailor's tape. A soft tape stretches and sags, and over two metres that adds up to a noticeable error.

Account for anything that sticks out inwards. Legs, corner brackets, slat fixings, headboard projections — anything that enters the space reduces the size the mattress has to fit into.

The 1.5 centimetre rule

Our factory's care rules contain two points that deal directly with size.

The first: it is prohibited to use a mattress that is more than 1.5 cm larger than the inside of the bed in length or width. A mattress squeezed by the frame bends, and the layers inside stop working as designed.

The second: the size of the bed must match the size of the mattress — if the mattress turns out smaller or larger, it deforms and cannot do its job properly. In other words, "let's take a bit bigger, just in case" and "let's take a bit smaller so it definitely fits" are equally bad ideas.

That is why an accurate measurement is not a formality. A one-centimetre error in a custom size cannot be fixed: the mattress has already been made for you.

What else to check in the bed before ordering

Size is not the only thing that decides how long a mattress lasts. The factory's care rules also set requirements for the base:

• A solid, flat surface or an orthopedic base with flexible slats. The gap between slats should be no more than 3.5 cm.
• For a mattress wider than 120 cm, a base with an extra fifth leg is recommended.
• Do not put the mattress on a bed with a wire-mesh base, on a sofa, or on any surface that sags like a hammock.
• For adjustable bases (with a raising head section), only mattresses designed for such bases are suitable. If you have one, mention it when ordering.

And one thing worth knowing in advance: on a base with flexible slats the mattress will feel slightly softer than stated because of the springiness of the slats themselves. This is also in the care rules.

If your bed has a lifting mechanism, there is also a limit on the mattress weight for the gas lift; see the article on beds with a lifting mechanism.

Spring or springless: it matters for delivery

If the mattress has to be carried up a narrow staircase or into a small lift, take that into account before choosing a model. The factory's care rules allow rolling and folding only springless mattresses made of latex or PU foam. A spring mattress must not be rolled or folded — neither during delivery nor afterwards: it damages the comfort layers and the spring unit.

How long it takes and how to order

Production takes 3–5 working days, and a custom size adds 1–2 days. The price of a custom mattress is calculated by a manager — it depends on the model and the size.

To order, send a manager on WhatsApp, or tell them by phone:

1. The inside length and width — the smallest of your measurements.
2. The model you liked in the mattress catalogue, or your weight and sleeping position if you have not chosen a model yet.
3. The type of base: slats, solid, or adjustable.

If you are unsure about your measurement, send a photo of the bed with the tape measure against it — it shows exactly where you measured from and to.

In short

1. Measure the inside of the bed, not the frame from the outside.
2. Length and width at three points; the smallest value goes in the order.
3. Factory rules: the mattress must not be more than 1.5 cm larger than the inside of the bed; one that is too small also deforms.
4. Base — slats with gaps of no more than 3.5 cm, or solid; for widths over 120 cm, with a fifth leg; not a wire mesh and not a sofa.
5. A spring mattress must not be rolled — keep this in mind if the staircase is narrow.
6. Production takes 3–5 working days plus 1–2 days for a custom size; a manager calculates the price.