Glass blocks are a building component which allow sunlight but obscure view. They are typically not load bearing unit and should not be used as such. Glass blocks are typically laid with Type S or Type N mortar with joints ranging from 1/4″ to 3/8″ thick. The most common dimensions manufactured are 6×6, 8×8, 12×12, and 4×8 with a standard thickness of 4″ or 3″ for thin units. There are several surface textures available and also different inserts and coatings that can control brightness, heat gain, and glare.
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