- Question: The Brick Industry Association recommends that only concave, V or grapevine tool joints be used. There are many other joint styles, such as extruded, beaded, raked, struck, weathered and flush, which all provide interesting aesthetic effects. Are architects limited to using only the three joints recommended by the BIA? I understand that these joints can be compacted and will presumably have less leakage. Is water penetration a problem in cavity walls that are well-designed? Can't other joints be experimented with to provide interesting architectural features?
Answer: The concave-tooled, V-tooled and grapevine-tooled joints do provide compaction, allowing less water to penetrate than some other joints. There are many other joints used in masonry construction, even in severe climates and freeze-thaw environments. Most of these joints, however, are used in residential construction where large overhangs protect them. Many joints, such as struck and raked joints, will permit additional water penetration, not only because of the lack of compaction but also due to ledges that are created that may direct water into the walls. While these joints have performed reasonably well in some buildings, there is a risk with using them. There may be increased efflorescence or reduced durability of the wall system.Selection of joints noncompacted should be done with caution to make certain that provisions are made either to limit the amount of water reaching the wall's face or to help the masonry dry, by providing vents and cavities within the wall system.