Unveiling Aesthetics: Brushed vs Smooth Mortar Joints

December 4th 2023 in Design


The difference in appearance between a smooth finished mortar joint and a brushed finish, is primarily due to the way light interacts with the surface texture and the exposed aggregate.



With our carefully graded aggregate, you can achieve different aesthetics by brushing (opening) the joint. The more the joint is brushed, the more aggregate is exposed.



When you point a joint with a smooth finish, you push the aggregate into the joint. The smoother finish gives the impression of a lighter shade of mortar.

Here's why the smooth finish often appears lighter in appearance compared to the brushed finish...

Surface Texture: A brushed finish has a textured surface with variations in depth and direction, causing light to scatter and create shadows. In contrast, a smooth finish has a flat and even surface, which reflects light more uniformly. When light hits a smooth surface, it bounces off in a consistent direction, resulting in a brighter appearance.  

Exposure of Aggregate: In a brushed finish, as the mortar is brushed back, some of the mortar is removed, exposing the aggregate within. We use carefully graded aggregate which varies in complementary colors and texture, creating a speckled or mottled appearance. 

The contrasting colors and textures of the aggregate withing the mortar can make the brushed finish appear darker and more visually complex, compared to the smooth finish.

Shadow and Depth: The textured surface of a brushed finish creates areas of shadow and depth where light is absorbed or scattered. These variations in lighting contribute to the perception of a darker appearance as compared to a uniform and well-lit smooth finish.

Visual Contrast: The exposed aggregate in a brushed finish can create visual contrast with the surrounding mortar, making it stand out and appear darker in comparison. This contrast can be especially pronounced when the aggregate is a different colour or texture.

Angle of Light: The angle at which light strikes the surface can also affect its appearance. In a smooth finish, light may reflect more directly off the surface, resulting in a brighter appearance when viewed from certain angles. In contrast, the textured surface of a brushed finish can scatter light differently, making it appear darker depending on the viewing angle.


Overall, the difference in appearance between a smooth mortar joint and a brushed one is a result of the interplay between surface texture, exposed aggregate, and how light interacts with these elements. 

While the smooth finish may appear lighter due to its even and reflective surface, the brushed finish offers a more complex and visually intriguing appearance, often appreciated for its depth and character.

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