How do I detail unfinished wood rainscreen siding?
I don’t like the idea of paint, stain, or wood preservatives. They’re expensive, a lot of work, and often toxic. Unshaped, wood boards are available, durable, relatively cheap, and easy to replace. Of all the siding options, unfinished wood benefits the most from a rainscreen, yet is proving to be very difficult to detail.
Two ways of installing board siding in a rainscreen fashion is vertically “board and batten” style, or horizontally as clap boards.
Board and batten rainscreen furring should be laid on the diagonal, or in a double layered cross-hatch pattern to allow for ventilation, support, and water drainage. Both are tough to detail, and irritating, I’ll just leave it at that.
The profile of clapboards is insect heaven, and I live in wasp-opolis. Painstaking attention to detail would be required to keep them out of the ventilation space. I don’t know how capillary gaps left above header flashings can be properly detailed to resist insect entry.
Going with shaped wood siding (channel, dolly varden, bevelled etc.) doesn’t have the issues of unshaped boards, but they’re more expensive, difficult to replace, and THINNER. Locally, shaped wood siding is 3/4″ thick, the thinnest parts being only 3/8″…. I question how long these profiles will hold up if left unfinished, even on a ventilated rainscreen. Does anyone know?
1) Forget about rainscreens, and rely on the durability of thick unfinished wood.
2) Have fun furring board and batten.
3) Go with clap boards and live with the wasps
4) Use a shaped siding and expect to replace it
Anyone have any advice? Sorry for introducing you to my madness,
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