Architraves Explained for Shutter Measuring

An architrave is the trim that frames the inside of a window or doorway. For plantation shutters, its shape matters because it can influence whether the shutter is fitted inside the recess or mounted onto the front of the trim.

In this article

• What kind of architrave do I have?
• How does each frame type work with an architrave?
• Why is an architrave necessary?

What is an architrave?

Architraves provide a finished border around a window and conceal the joint where the window opening meets the wall lining. Not every window has one, but where an architrave is present its shape and available flat surface should be checked before selecting the shutter frame.

What kind of architrave do I have?

For shutter planning, most architraves can be grouped into three practical categories.

Bullnose architrave

A bullnose architrave has a relatively flat front face with a rounded outer edge. It normally works well with both inside and outside shutter mounting where sufficient clear surface is available.

Decorative architrave

For the order, decorative trim contains grooves, steps or moulded profiles. An inside L-frame can be particularly useful because it leaves the decorative front face visible.

Square architrave

A square architrave has straight edges and a broad flat face. Its simple shape makes it one of the easiest architraves to work with for shutter installation.

How does each frame type work with an architrave?

Z-frame with architraves

For this step, a Z-frame sits inside the recess and overlaps the front edge of the opening. It works particularly neatly with square and bullnose trim. With decorative architraves, check where the lip will land so it does not cover a moulded detail.

Inside L-frame with architraves

An inside L-frame stays within the recess, so it can work with virtually any architrave provided the recess has enough depth. It is especially useful when you want decorative trim to remain completely visible.

Outside L-frame with architraves

For the order, an outside L-frame fixes to the front face of the architrave. You therefore need a continuous flat band wide enough for secure fixing. Decorative trim can still be suitable if there is a flat central section.

Why is an architrave necessary?

The architrave is primarily a finishing element rather than a structural part of the window. It hides joints around the opening and gives the wall-to-window transition a deliberate, finished appearance.

For shutters, its practical importance is the surface it provides around the opening and how that surface interacts with the selected frame.