Bed Joint
/BED joynt/
Also known as: bed mortar, horizontal joint, mortar bed, horizontal mortar joint
Definition
The horizontal mortar joint between successive courses of bricks or blocks in a masonry wall. The bed joint distributes loads evenly across the masonry, bonds the units together, and accommodates minor variations in unit size.
In Practice
Standard bed joints in brickwork are 10mm thick. Thinner joints (2-3mm) are used with thin-joint mortar systems for aircrete blocks. Overly thick bed joints weaken the wall and are a sign of poor workmanship. In structural masonry, joint thickness is specified by the engineer.
UK Building Regulations
Approved Document A - Structure
Eurocode 6 (BS EN 1996-1-1) governs the design of masonry structures including mortar joint requirements.