Rough-Sawn Pine for Rainscreen Furring
Hi,
We just placed our Mento 1000 WRB on my new garage (a part of a house/garage build) and I brought my roughsawn pine 1×4 material to the guys for installing our rainscreen layer.
They asked if they should prime/paint the battens or if I wanted to use treated lumber instead since they were rough sawn local pine. They said that won’t last as long as kiln-dried 1x4s.
In my experience on GBA, it seems that everyone is using just plain wood for their rainscreen layer and not treated very commonly.
So, is there a difference between my air-dried local roughsawn pine and the kiln-dried you buy at the lumber yard?
Can I use it as-is or should I be concerned enough to prime or seal it?
This is all going to be behind board and batten siding.
Thanks!
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Replies
How green are the furring strips / battens ? If they're relatively fresh off the saw, they're likely to crack / split as they dry. If they've been seasoned for a while and have come to equilibrium MC (more than a year), I'd say you're probably fine with priming them. Part of the KD process prevents rotting and sets the sap so that it doesn't ooze out and stain the boards down the road. That pine will be bleeding all over the place in time unless you block it somehow. With treated you have to be careful - all galvanized nails aren't created equal.
Hi Kyle,
I have plenty of many-year air-dried 1x4s. With the cost of wood right now, I was hoping to use what I already have. That said, priming that many will be really time consuming... Do I need to prime? Is that completely necessary?
I wouldn't anticipate them oozing any sap or anything given that they're already as dry as things get at outdoor MC.
My thought is that a roughsawn 1x4 would last pretty much forever inside of the rainscreen gap and never directly exposed to weather but I want to make sure and get feedback before I put them up...
If they're seasoned like that, I'm sure they're fine. Just wanted to throw it out there in case they were still oozing :).
With a rainscreen gap I think they will be fine as is. You could do a borate treatement if you are really worried, but I think they'll be fine unless they somehow get damp, but you don't want them to get damp in any case.
Michael,
I would have no reservations about using them. If the conditions in your rain-screen cavity are capable of rotting the 1"x4"s, y0u have more pressing concerns to worry about than whether they were primed or treated.