Caulking Cedar Siding Joints

It needs to move and breathe.

Caulking cedar siding joints.

This is a high performance formula that comes in a 10 1 oz bottle. Butt joints but not all butt joints. I m about to put up siding on a building enclosure that includes a wrb taped xps and furring strips. The answer depends on the manufacturer and installation method used when the siding was first installed.

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. Caulk by its adhesive nature will try to limit this movement leading to widespread failure and cracking in the caulk over time. The siding will be a combination of lap wood siding front and colorplus hardie plank the rest. The siding expands and contracts with temperature and humidity.

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. Generally we do not recommend caulking butt joints on cedar siding. If i install a non finished product i usually go with a 3m paintable caulk. If you re in the market for the best exterior caulk for cedar siding you will appreciate what the red devil 077010 has to offer.

My question is limited to the seams in which the siding contacts vertical trim. Siding caulk can be used on several different areas of your exterior siding to help prevent water damage and moisture buildup. Most other areas were caulk is necessary should be lightly smoothed with your finger. Some of the most commonly caulked areas of siding include both corners and crevices as well as some butt joints and window and door trim boards.

The hole should be about 3 16 of an inch for most caulking joints. I am in agreement with martin not to use caulking as it seems to cause more. Think of a wood home as a living thing. Natural siding boards are designed to expand and contract with the elements and we do not want any adhesive to prevent their natural movement.

If i am installing a prefinished product which i do mostly i use a color osi match caulk. All butt joints will be flashed. Should they always be caulked. Where two pieces of siding meet.

When you try to restrict either it is at your peril.