Sealing Siding Joints

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.

Sealing siding joints.

Lp smartside is. How much space do you need between lap siding pieces. Do i have to caulk at butt joints. On older installations of hardieplank lap siding the field butt joints would have an appropriate gap which at one time was specifically designated as 1 8t.

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. In other words caulking is applied where moisture would otherwise penetrate and cause deterioration. Lp siding requires flexible exterior grade paintable caulk to seal gaps. 25 4 mm on overlap no caulk figure 1 figure 2 9.

Caulking is a sealant that fills gaps cracks nail holes and similar imperfections on the surface. Siding planks see figure 2. In this article we will go over typically caulked areas on the exterior typical northwest style homes and also areas that should never be. 2 house built before 2008 so has no flashing okay to caulk.

We also provide a master index to this topic or you can try the page top or bottom search box as a quick way to find information you need. Proper sealants are important for preserving the integrity and warranty of lp siding. 3 16 gap at butt joints between horizontal sections and where the siding meets doors windows and corner trim. 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.

It depends on the option you choose but if joint caulking option is selected seal all gaps at butt joints with a high quality exterior sealant meeting the astm c920 minimum class 25 sealant. It is great for sealing a wide range of places around the house from doors and windows to bathtubs and 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. Although lp building products siding is available bare or painted cutting the materials to fit during installation exposes some areas to the elements.

Tthis article gives specifications for proper flashing sealing detailing at building siding joints corners and window or door openings to provide an attractive and durable job that doesn t leak or rot. 1 i chose this caulk because it has 25 flexibility compared to silicone based caulk.