Installation Instructions

Allura Fiber Cement Siding Installaon Manual
49
Butt End/Joint Covers
Do not caulk fiber cement butt joints/edges.
Applying caulk to the butt joint is ineffective because the gap is not large enough to
accommodate the sealant. Also, on prefinished products, caulk may leave an unsightly
looking finish. Spreading or feathering the sealant into a thin film will create a noticeably
different appearance, and it can remove the needed thickness required to withstand UV
exposure and joint movement.
Joints Where Solid Framing or Structural Sheathing Are NOT PRESENT
If boards cannot be joined into solid framing or structural sheathing, you must use an
off-stud joiner behind the joint. Off- stud joiners are available in different sizes. Choose
the joiner that is the correct size for the siding you are installing.
1. Insert the off-stud joiner onto the butt end of the siding. Align the center of the
joiner with the end of the siding.
2. Insert the edge of the next panel of siding into the other side of the joiner.
3. Make sure both butt edges of the board are either factory-sealed or sealed after a
cut. Then butt the ends of boards together.