To back-prime cypress siding, or not? That is the question.
rockinroger
| Posted in General Questions on
A couple of my fellow contractors were discussing the merits of back-priming cypress siding the other day, and one is for back-priming siding, and the other one believes that the siding needs to breathe.
I personally think that it is not necessary.
What do you think?
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Replies
All species of wood benefits from being sealed on all six sides. It prolongs the life of the siding. Leaving the back un-primed is what causes the finish to peel and flake.
Roger,
I agree with Malcolm. If the back side of the siding is unprimed, and the front side is primed and painted, then it's easier for the siding to absorb moisture from the back of the siding. When the sun comes out, the front of the siding is dry, while the back of the siding is moist. This leads to curling and splitting.
If you want wood siding to dry quickly, and you should, always install the siding over a ventilated rainscreen gap. For more information on this issue, see All About Rainscreens.