Leaving pine shiplap siding unfinshed
ranson
| Posted in General Questions on
I’m planning on siding my house with locally sourced shiplap installed horizontally with a rainscreen gap. The house has generous (2′-6′) overhangs all around. I know that unfinished wood has been used on farm buildings for a long time. However, farm buildings can let in a little water and smell a little mildewy without causing to much trouble. I do like the unfinished look.
If protected by overhangs and proper water management, am I making my siding more likely to fail by leaving it unfinished? Is there any treatment that I should consider to make the wood last longer?
John
Rochester, NY
Zone 5
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Total Wood Protection clear formula.
John,
As long as the siding is protected from splashback, it will last indefinitely, even without any finish. An examination of old barns will be instructive.
I built a house with board-and-batten siding in 1974, and the siding was never treated in any way. Forty-two years later, the siding is fine.
What species of wood? I've seen hemlock and larch siding last a long time in upstate NY even where rained on. Some of the store-bought pine and spruce won't last unfinished. You'll probably get splash on your siding no matter the overhang. Two story house?
John:
Wood species have different properties, of course. Some are prone to warping, for instance. But, I think almost any variety will last indefinitely, inside for sure but even out, protected from water. Here in New England, locally available softwoods such as northern white pine, spruce, fir and cedar have all been used and would be fine, especially with your generous overhangs.
The wood will however weather naturally, and the look will be different on different sides of the house, resulting from the varied exposure to sun. This bothers some folks, but certainly looks natural and oftentimes is quite beautiful, just varied.
BTW...
With your rain screen, and probably a paper over sheathing, and esp with your overhang, this will be much tighter than a barn. And water that intrudes (from a hard, wind driven rain), should soon dry out because of your rain screen and WRP. I think vertical application is a little bit better for shedding any rain water, but not so much that you shouldn't go with your aesthetic preference.