Control joints have which type of flanges?

Control joints have which type of flanges?

• A. Plain
• B. Perforated
• C. Expanded
• D. All of the above

Answer: (D)

Control joints are placed to accommodate movement in plaster and stucco so cracks form along the joint rather than across the surface. The flange on a control joint is the part that sits against the plaster edge and helps anchor and key the joint to the substrate. Different flange styles are used to achieve different levels of adhesion and grip: plain flanges provide a simple edge, perforated flanges have holes to allow plaster to key through and improve bonding, and expanded flanges offer more surface area and a stronger mechanical grip to distribute stresses. Because engineering and substrate conditions vary, any of these flange types can be used on control joints, so the best practice is that control joints can have plain, perforated, or expanded flanges.

Control joints are placed to accommodate movement in plaster and stucco so cracks form along the joint rather than across the surface. The flange on a control joint is the part that sits against the plaster edge and helps anchor and key the joint to the substrate. Different flange styles are used to achieve different levels of adhesion and grip: plain flanges provide a simple edge, perforated flanges have holes to allow plaster to key through and improve bonding, and expanded flanges offer more surface area and a stronger mechanical grip to distribute stresses. Because engineering and substrate conditions vary, any of these flange types can be used on control joints, so the best practice is that control joints can have plain, perforated, or expanded flanges.