## Lock in Boards and Seal Joints to Enhance Cement Board Siding's Performance Installing cement board siding requires securing the boards firmly in place and sealing the joints to prevent water infiltration. Here's a comprehensive guide on locking in boards and sealing joints for optimal performance: ### Locking in Boards * **Stagger Board Joints:** Offset the joints between adjacent boards horizontally and vertically to distribute the load and enhance stability. * **Nail or Screw Boards Securely:** Use galvanized nails or screws to fasten boards directly to the studs at regular intervals. * **Drive Fasteners Flush:** Sink the nails or screws slightly below the board surface to prevent protruding heads that could compromise the siding's integrity. * **Use Correct Fasteners:** Select fasteners specifically designed for cement board siding that will not corrode or weaken over time. ### Sealing Joints * **Apply Backer Rod:** Fill joint gaps with a backer rod made of foam or rubber to seal against air infiltration and provide support for the sealant. * **Use Elastomeric Sealant:** Apply a flexible elastomeric sealant over the backer rod to create a watertight barrier. * **Tool Joint:** Smooth the sealant along the joint using a sealant tool or trowel. Ensure it is flush with the board surfaces. * **Avoid Over-Application:** Sealants can shrink or crack if applied excessively. Use a moderate amount to fill the joint without creating ridges or bulges. ## Additional Considerations * **Use a Vapor Barrier:** Install a vapor barrier behind the cement board siding to prevent moisture from penetrating the wall cavity. * **Inspect and Clean Regularly:** Periodically check the siding for signs of damage or wear. Clean it regularly to remove dirt and debris. By carefully locking in boards and sealing joints, you can ensure the longevity, durability, and water resistance of your cement board siding. This will safeguard your home's exterior and enhance its overall value.