What is a Flap Stay? Differences from Gas Struts
A flap stay is a mechanical furniture fitting that holds upward- or downward-opening cabinet flaps in a defined position and decelerates their movement. A gas strut, on the other hand, uses a nitrogen-filled cylinder to actively push the flap upwards using pneumatic force and gently cushion it upon closing.
What exactly is a flap stay?
A flap stay (often also referred to as a friction flap stay) is a purely mechanical component within flap fittings. It usually consists of a metal articulated arm featuring an integrated friction brake. This brake ensures that the cabinet door does not fall down unchecked when opened, or that it remains in the desired position when lifted upwards. On many models, the braking force can be adjusted precisely to the weight of the front via an adjustment screw.
The difference: flap stay vs gas strut
Although both terms are often used interchangeably in everyday installation, they differ fundamentally in their mode of operation:
- Mechanical flap stay: Works using frictional resistance. It supports the flap and cushions the falling movement. The installer must manually move the flap to its end position. This mechanism is ideal for downward-opening fronts (drinks cabinets, secretaires).
- Pneumatic gas strut: Works using compressed gas. Much like a car tailgate, the cylinder takes over the lifting work beyond a certain opening angle and pushes the front upwards automatically. It is primarily suited to upward-opening wall units.
Types and variants for furniture assembly
Depending on the carcass construction and the weight of the front, different components are utilised:
- Lift-up fittings: For standard wall cabinets. Here, the gas strut is the most common solution for cabinetmakers, as it makes operation significantly easier.
- Heavy-duty fittings: Large MDF or solid wood fronts require considerable supporting force. For these applications, gas struts for heavy flaps are installed, which are calibrated precisely to high door weights.
- Flap supports for downward-opening doors: Classic flap stays with a hinged joint that stop the front from dropping down and hold it horizontally at a 90-degree angle.
Dimensions, standards, and typical values
When selecting gas springs, the nominal force rating is crucial. This is specified in Newtons (N). Incorrect dimensioning means the flap will either fail to stay open (strut too weak) or will be very difficult to close (strut too strong).
- Lightweight fronts: 50 N - 80 N
- Medium-weight fronts: 100 N - 150 N
- Heavy fronts: 200 N - 350 N
- Installation length: Typical cylinders feature an overall extended length of approximately 268 mm.
Calculation note: As a rule of thumb for installation, 10 N corresponds to a lifting force of approximately 1 kg. A flap with a weight of 3.5 kg therefore requires a supporting force of at least 40 N. In practice, installers typically fit a 50 N model or mount two struts (left and right) rated at 20 N - 30 N each to prevent warping of the front.
Application and visual integration
Alongside pure lifting capacity, interior aesthetics play a vital role in modern furniture. Fittings are selected to harmonise with the carcass decor. For dark wood decors or anthracite interiors, installers choose a black gas strut. For bright, melamine-faced chipboard, a white gas strut blends in discreetly. For universal, technical accents, classic silver gas struts are typically installed.