Caulking Between Wood Siding

Matt is 100 correct.

Caulking between wood siding.

Any contractor worth their salt knows that you never caulk anywhere where water may need to escape. Best for use with drywall wood and masonry. Think of a wood home as a living thing. Sometimes known as acrylic latex caulk.

In fact some manufacturers warranties are void if you do. Bottom of siding boards should not be caulked water is meant to exit through the bottom of each board. 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.

Most other areas were caulk is necessary should be lightly smoothed with your finger. The hole should be about 3 16 of an inch for most caulking joints. It needs to move and breathe. The siding expands and contracts with temperature and humidity.

You never ever caulk the underside of lap siding. Fill in gaps between crown moulding and baseboards. Use latex painter s caulk inside of doors and windows or to quickly fill cracks. While paint does tend to somewhat glue these pieces together caulking them is never advised and can cause permanent damage.

In my opinion caulking between the seams in any lapped siding either horizontal or vertical is not good practice but not just because of any potential vapor barrier effect. Placing caulk over large portions of wood siding prohibits the natural movement of the wooden panels and can cause extensive damage to the exterior of your home.