Hinges, latches and hardware
The parts nobody photographs, and the parts that decide whether the door still closes properly in two years.
Range being built
How many hinges
Three hinges is the usual answer for an internal door: two carries the weight badly and lets the door twist over time, particularly on solid timber. Heavier doors and fire doors have their own requirements, and on a fire door the number and specification of hinges is part of what was tested.
[VERIFY: manufacturer installation instructions] before deviating on any certified door.
Hinge size follows door weight
A standard butt hinge suits most internal doors. Once you are into solid oak or a 44mm fire door, the leaf weight climbs steeply — a 44mm door is roughly 40% heavier per square metre than a 35mm one — and the hinge has to be sized for it. Our product pages carry an estimated leaf weight for exactly this reason.
Intumescent strips and smoke seals
On a fire door, intumescent strips expand in heat to seal the gap between door and frame. A separate brush or fin seal handles cold smoke, which is what the S in a rating like FD30S refers to. They are not interchangeable and not optional where they were part of the tested assembly.