Caulking Hardiplank Lap Siding

It will look okay on day one but caulk is not designed to be used as a touch up and it will weather at a different pace than the siding.

Caulking hardiplank lap siding.

Flashing acts as a waterproofing layer for this type of siding and caulking will prevent the flashing from doing its job. Many professionals like those at james hardie also agree that you should not use caulk on fiber cement siding unless there is no metal flashing underneath. 152 4 mm wide 1 in. This video is about how to like a pro.

25 4 mm on overlap no caulk figure 1. Osi quad product brochure. Is the old caulking removed before new coats are applied. Deterioration of the caulking in the joint has become a maintenance issue for home owners over time.

Hardie no longer recommends the caulking of any joint in their lap siding colorplus or primed. 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. Apparently no one here read the technical bulletin 9 that james hardie released in 2008. James hardie also does not recommend applying caulk to the horizontal overlap between siding planks see figure 2.

Joint flashing is recommended for all hardie lap siding now. Caulking around windows doors eaves and trim edges gives added insurance that leaks will not occur. This technical bulletin is an explanation supporting the announcement made by james hardie on september 8th 2008 withdrawing its recommendation on the use of caulk at field butt joints for hardieplank lap siding. 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.

Lastly james hardie does not allow the use of colour matched caulking for touch ups. 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. James hardie color match caulk osi quad caulk for exterior door window and siding applications color matched to james hardie colors uv water resistant will not crack or yellow 1 tube covers 29 lineal feet at 1 4 bead width or 13 lineal feet at a 3 8 bead width paintable.