Caulking Lap Siding

Whether you are repainting replacing a window or replacing the siding on your house the caulking around the window trim is a very important element.

Caulking lap siding.

Is the old caulking removed before new coats are applied. Caulking around windows doors eaves and trim edges gives added insurance that leaks will not occur. When deciding how to use caulk on your siding however it is generally more important to consider where you should not use it. It is generally not a good idea to use caulking on wood siding.

Think of a wood home as a living thing. 25 4 mm on overlap no caulk figure 1. Caulking your home s siding is a simple process but not necessarily a foolproof one. Caulk is by necessity a sticky gooey substance and as such it smudges easily.

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. And many homeowners over caulk applying caulk where it doesn t belong and potentially compromising the performance of their siding. When you try to restrict either it is at your peril. Caulk by its adhesive nature will try to limit this movement leading to widespread failure and cracking in the caulk over time.

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. The nails holding up the siding should not be caulked. A diyer or a novice painter might attempt to achieve a cleaner look by caulking the siding nails but the nail is guaranteed to push the caulking material out within a few months.

Similar to paint previous coats of. If overused or incorrectly placed siding caulk can cause more damage to your exterior than good. It needs to move and breathe. James hardie also does not recommend applying caulk to the horizontal overlap between siding planks see figure 2.