Steliz":1mkuxhs2 said:
There was some translating going on between us so I'm not 100% sure what the actual definitions of dry and not dry are.
Can anyone clarify this based on UK experience? Obviously, I want the wood to be dry enough for the purpose but will I be OK with wood described as 'not dry'? Perhaps the opportunity to save money is clouding my judgement here?
Basically, here in the UK 'dry' construction grade timber for the construction industry means wood that has been dried to 20% MC or lower. There's a bit of give allowed in the quality control for testing large batches of wood coming out of the kiln of approximately 4 percentage points. In other words, if a batch of wood comes out of the kiln followed by a representative sampling of pieces tested, and most samples read, say ~18% MC and a few read up to 24% then that batch is considered 'dry' for the purposes of strength testing and grading, the results of which are marked on the pieces.
'Dry' from a furniture maker's point of view, or anyone else making internal joinery, such as doors and other artefacts that fit within the walls of habitable buildings (rather than, say, external garden furniture) need their wood drier at somewhere between roughly 7% MC and perhaps 12 - 13% MC.
You are building a pergola, which is presumably outside, so I imagine you won't need it especially dry, all depending upon where you live, which you say is not in the UK. A good moisture content for that type of construction is likely to be anywhere between roughly 20% MC and even perhaps green, i.e., basically unseasoned, again, dependent upon where you live, and also dictated by your design, which could be anything from fairly delicate and engineered to chunky and rustic.
On the other hand, I'm not sure 'pine' is the ideal choice for a pergola because most 'pines' aren't especially durable in ground contact, so be a bit careful about which 'pine' you're buying - there are several pine species that might (or might not) be available. Alternatively, you could consider using tanalised wood, or make your pergola out of something with known natural ground contact durability, such as oak ... and you might have a pergola design that lifts your not especially durable wood (pine?) away from the ground, such as brick or block piers or a wall of some sort maybe 8" - 12" high that the sit under the wood. Slainte.
