Nominal Force in Newtons (N): What Does the Rating on a Gas Strut Mean?

June 13, 2026

The nominal force in Newtons (N) indicates how much force a gas strut cylinder exerts when extending, in order to lift a furniture flap and hold it open. Ten Newtons roughly correspond to a lifting force of one kilogram, which is why the N rating must be matched precisely to the weight and height of the flap.

What Exactly Is Nominal Force?

A gas strut (often also called a gas spring) is a hydropneumatic adjustment fitting. High-pressure nitrogen gas is contained inside the cylinder. Similar to a heavily preloaded bicycle pump, the compressed gas pushes the piston outwards. The force with which this occurs is called the nominal force and is measured in the physical unit Newtons (N).

In furniture making, these components take on the active lifting of upward-opening cabinet flaps. They must be strictly distinguished from a passive door damper (soft-close), which merely decelerates the closing speed but does not generate any lifting force of its own.

Typical Values and Dimensions in Furniture Construction

Choosing the correct force rating is crucial for the smooth operation of the flap. If the strut is too weak, the door will drop down. If it is too strong, the cabinet can only be closed with great effort, and the hinges will be overloaded.

Standard values for wall units in kitchens or living room furniture are typically:

50 N / 60 N / 80 N (for lightweight flaps)
100 N / 120 N / 150 N (for standard MDF or chipboard panels)

For large-format fronts or solid wood fronts, dedicated gas struts for heavy flaps are used. Here, the range often extends from 200 N up to 400 N or 500 N.

In addition to force, installation dimensions are relevant. A typical standard strut has an overall length of around 268 mm when extended. The stroke — the maximum extension travel of the piston rod — is usually about 90 mm.

Calculating Gas Springs: How to Determine Your Requirements

To determine the required nominal force for a furniture flap, two core factors must be known:

The exact weight of the flap in kilograms (including fittings and furniture handle).
The height of the flap in millimetres.

Because leverage plays a major role during opening, a generic conversion (1 kg = 10 N) is not sufficient for the mounting position. Fitters use the following rule of thumb to calculate flap fittings for a 90° opening angle:

(Flap height in mm ÷ 2) × Flap weight in kg × 0.11 = Required force in N

Example: A flap is 400 mm high and weighs 4 kg. (400 ÷ 2) = 200. 200 × 4 = 800. 800 × 0.11 = 88 N.

Since struts should always be fitted in pairs (left and right) to prevent warping of the front, this value is divided by two. In this case, two struts rated at 50 N each would be the technically correct choice.

Installation Notes

Mounting is generally carried out using screw-on brackets on the cabinet carcass and front panel. For a permanently secure fit in chipboard, suitable wood screws and furniture screws (usually 3.5 mm or 4 mm diameter) should be used. The exact drilling dimensions and distances from the hinge depend on the desired opening angle (usually 75°, 90°, or 110°) and can be found in the manufacturer dimension sheets.

Related Terms

Stroke: The usable length over which the piston rod travels out of the cylinder.
Flap stay: A purely mechanical flap stay operates without gas pressure, relying instead on friction or spring force to hold a flap in position.
Damping: Usually refers to the soft-close mechanism in the hinge, rather than the lifting force of the gas strut cylinder.