How To Seal Hardie Board Siding Joints

Joint flashing is recommended for all hardie lap siding now.

How to seal hardie board siding joints.

It is similar to traditional beveled wood lap siding. Apparently no one here read the technical bulletin 9 that james hardie released in 2008. Hardie no longer recommends the caulking of any joint in their lap siding colorplus or primed. If you have loose hardieplank siding on your home it is important to fix it.

Butt joints are a perfect example of poor joint design they re too small to accommodate a bond breaker so the caulk can t stretch properly once applied but they re also too large to simply leave alone. Laps will need to be periodically removed and or reapplied to maintain the seal over the life of the building. This has proven problematic over time as caulking the joint results in unsightly surface appearances due to the different textures as well as resulted. But here the main problem is people usually don t find the right type of caulk for their works.

Hardieplank is a brand of fiber cement board that is used for exterior siding projects. Joining hardie boards together is actually very easy but there are a number of ways that contractors get it wrong. James hardie recommends butting field joints together in moderate contact to achieve a continuous looking joint. James hardie believes it is good building practice to seal the joints to prevent moisture such as wind driven rain and snow from penetrating the wall cavity.

A common problem with cement board siding products and some other types of horizontal lap siding is that older installation guidelines called for caulking the joint instead of flashing the joint. Hardie plank joints butt joints james hardie siding is 12 feet long which means that siding on your longer walls will need to join together. Caulking around windows doors eaves and trim edges gives added insurance that leaks will not occur. Deterioration of the caulking in the joint has become a maintenance issue for home owners over time.

Hardie boards should be joined in moderate contact. If you use sashco s acrylic latex caulking sealant you can have any interior or exterior as good as new. A lot of moisture from rain snow misdirected sprinklers or exuberant water fights can get in there enough to do some serious and expensive damage.