The thickness of a modern external wall typically ranges from 23cm (9 inches) to 30cm (11.5 inches), plus any internal plastering and external rendering. The exact thickness depends on whether the wall is a solid wall or a cavity wall.
Here's a breakdown:
-
Solid Wall: A solid wall will generally be around 23cm (9 inches) thick before the application of internal plaster and any external rendering.
-
Cavity Wall: A cavity wall, which is more common in modern construction, tends to be about 30cm (11.5 inches) thick, excluding plastering and rendering. The cavity itself is an important factor in insulation and damp prevention.
Therefore, to determine the total thickness of a modern external wall, you would need to measure from the outside face of the exterior finish (rendering, brick, etc.) to the inside face of the interior finish (plasterboard, plaster).
