Should clapboard Metal corner caps be caulked?
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Hi all, we are installing primed and painted vertical grain clapboard siding on our home and looking into using aluminum corner caps on the outside corners rather than corner boards. I’m wondering if each corner cap should be caulked to prevent water from getting between the aluminum cap and the clapboard?
We will be using cor-a-vent sv3 and studi strips to allow for ventilation behind the siding, I’m not sure if that makes a difference or not in regards to my question but I thought I would include it.
Replies
I have no idea on caulking but do recommend sealing all cut ends or penetrations of the siding.
Thank you, Calvin! We are currently priming all sides of the clapboard now prior to install and any cut ends during installation we plan to prime as well.
FWIW, I've never seen those corner caps caulked & I haven't noticed any resulting problems. OTOH, with corner boards, you're dependent on caulk. And no manufacturer I know will guarantee their caulk for any significant time, if for no other reason than the quality of the installation is very dependent on the skill and dedication of the installer. OSI is a well respected caulk supplier- here's their guarantee: https://www.ositough.com/en/meta/footer-nav/warranty.html
Since you're going with a vented rainscreen installation, any moisture that makes its way past the metal corner caps has a good chance of evaporating before it causes problems.
The siders I've dealt with don't like those metal caps- they require more skill and precision than corner boards, which will disguise alignment errors.
Thank you, bobbomax!
The alignment with the metal caps was a concern of mine that it will result in increased time/labor and therefore cost.