Caulking For Fiber Cement Siding

So what i would tell you to do is to use a colored caulk to choose the caulk in the color of the siding.

Caulking for fiber cement siding.

Dap alex plus 12 pack 10 1 oz white paintable latex caulk. Applying caulk to the butt joint is ineffective because the gap is not large enough to accommodate the sealant. 1 i chose this caulk because it has 25 flexibility compared to silicone based caulk. Caulk is usually used with fiber cement siding to prevent water intrusion at the butt joints.

Flashing acts as a waterproofing layer for this type of siding and caulking will prevent the flashing from doing its job. Caulking around windows doors eaves and trim edges gives added insurance that leaks will not occur. Item 157140 model 11532. When james hardie siding products butt into wood based materials a 1 8 gap will allow for expansion and contraction of the wood based product.

The specification to omit caulk at siding butt joints is for new installations and is discussed in detail by the manufacturer. 2 house built before 2008 so has no flashing okay to caulk. Do not caulk fiber cement butt joints edges. We only caulk butt joints on cedar siding if previously caulked.

Fiber cement boards are caulked only when there is no metal flashing behind them. Fiber cement boards don t expand and contract much but leave a little room for expansion at the end joints and then fill the gap with caulk. And this way you don t have to worry about painting it and you could still have the qualities of expansion and contraction and adhesion so it ll stay put once you apply it. Some manufacturers do not require the metal flashing therefore we caulk the butt joint to keep the pieces together and also prevent moisture.

Trim boards wood windows.