Window and door frames (joinery)

Window and door joinery covers every opening or fixed element that closes the window and door openings of a building. The frame fixed to the wall, the opening sash, the glass, the seals and hardware such as hinges and handles together form a joinery system. By material, systems are described as uPVC, aluminium, timber or timber-aluminium composite. The Turkish trade term is doğrama.

Types by material

uPVC frames are common in housing for their good insulation and reasonable cost. Aluminium allows slim profiles and large openings, though thermally broken profiles with an insulating barrier should be the default. Timber gives warmth and is often required on historic buildings, but it needs regular maintenance. Composite systems combine the warmth of timber inside with the durability of aluminium outside.

What to check when choosing

• Energy performance depends as much on the glazing and the quality of installation as on the profile.
• If the junction between wall and frame is not sealed properly, even the best window will leak air and water.
• The opening type, whether side-hung, sliding or tilt, is chosen together with furniture layout and ease of cleaning.

Joinery sets the rhythm of a facade and the light inside. When profile widths, sash divisions and glass reflections in a render match the real product, a building immediately looks more convincing.