Yes lots of dimensional lumber gets sold in the US from Canada but lately I have noticed that a 2x is no longer the 1 1/2 inches that it was for many years. My guess is that it really measures 37 or 38mm. To someone with an SAE type tape measure it looks a lot like 1 15/32 inches or maybe closer to 1 7/16 inches.
they are not going to change anything, think about the repercussions. windows doors, insulation etc. domino effect.
That's right, there are a lot of things that would be effected, or impractical to convert. The only way we could have metric dimensional lumber sizing would be to have a whole new system right along side the old imperial system, which would mean lumber yards would have to be twice as big. I don't know if that has anything to do with metric sizing, but I have found that 2x4s can vary a lot more then that in size due to their moisture content, so maybe what you are seeing is just some very dry lumber?
In our company we say "do your best and caulk the rest" Or "if you wanted a perfect job, you should have taken the highest bidder" that usually gets the inspector going
I still have to think about personal measurements that show up on our government documents like licenses. I'm 182 cm tall but only weight 132 kg's. However it does have some advantages....18 cm sounds way bigger than 7"
