Caulking Siding Joints

Apply these strips in place of traditional caulk or over already caulked joints for a finished appearance.

Caulking siding joints.

When deciding how to use caulk on your siding however it is generally more important to consider where you should not use it. Caulking around windows doors eaves and trim edges gives added insurance that leaks will not occur. These siding joints can be caulked successfully if the gap is wide enough for the caulk to get into the crack. 25 4 mm on overlap no caulk figure 1.

Generally we do not recommend caulking butt joints on cedar siding. Caulk is the durable waterproof paste that s used as a sealant in joints and gaps to keep dirt pests moisture and exterior air at bay. 152 4 mm wide 1 in. 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.

Those joints need to be protected somehow. Where two pieces of siding meet. Joint flashing butt joint horizontal lap treatment june 2014 james hardie does not recommend caulking butt joints or the horizontal overlaps joint flashing 6 in. Although i do not understand why they have not changed the information about caulking in the instruction manual.

There s no way around regular maintenance of those siding butt joints unless you want to completely remove the siding and install joint flashing. Deterioration of the caulking in the joint has become a maintenance issue for home owners over time. It is generally not a good idea to use caulking on wood siding. While as a diyer you might be obsessing about your caulking skill truth be told that will not matter if you don t have the right caulk.

If the siding joint is so tight that the caulk only bridges the gap it may split again. Joint flashing is recommended for all hardie lap siding now. Should they always be caulked. Caulk backer rods are lengths of foam that help fill large gaps before caulking.

Butt joints but not all butt joints. If overused or incorrectly placed siding caulk can cause more damage to your exterior than good. Similar to weatherstripping caulk strips are pre shaped rolls of sealant that have a peel and stick installation. Natural siding boards are designed to expand and contract.