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How to perform architectural grooves "Ashlar"cuts finish with Monocouche




Ashlar masonry

Ashlar masonry is a type of building construction that uses primarily rectangular blocks of stone. Using techniques dating back thousands of years, ‘ashlar’ masons can create walls, arches and buildings through correct placement and varied sizes of rectangular blocks.

Ashlar masonry is seen in many ancient buildings, and still plays a major part in construction in some parts of the world.



Ashlar in modern buildings

In modern buildings, depending on the building architecture, it is possible to perform the\same ancient ‘ashlar’ effect, when using a colored render like Monocouche.


Ashlar effect using weber.pral F, weber.pral K

Apply weber.pral F or weber.pral K to the minimum thickness of the render with regard to the exposure conditions. In most exposure conditions the depth of profile of the ‘ashlar’ will be varied between 5 and 10 mm. Which cut is chosen it is important to maintain at least 15 mm of render at the lowest point. In areas of severe exposure the recommended minimum coverage at any point should be increased to 20 mm. The total finished thickness of render should not exceed 25 mm in any application.

While the render is still green (i.e. set but not yet full hardened) immediately after scraping finishing mark out ‘ashlar’ cuts using chalk line.

Place tomber battens so the point of the ‘ashlar’ cutting tool TK 11, TK 20 or TAT (see tools page.125 ) will remove the chalk line.

Run the ‘ashlar’ cutting tool along the batten until the specified depth of the cut is achieved.

Immediately after cutting, brush using a clean soft bristle brush to remove dust.



Using this ‘ashlar’ technique the traditional stone masonry effect can be achieved without using the expensive and difficult stonework.

Solution with the following weber products


weberpral F

One-coat mineral decorative rendering mortar


weberpral K

Decorative single layer render


webercal palm

Decorative arabian render for internal and external use