erm because people profer it not to small or not to big
it is cat into useful size so their is big and not fiddle piece
P.A.R. or PAR means Planed All Round when used in reference to timber. In other words, the timber has been prepared. The alternative is rough or sawn or unprepared timber. This has been cut to size but not finished in any way. Timber that is PAR is planed but there is no guarantee that the corners will be square!
Timber is to lumber as quarry is to stone because timber is where cut lumber comes from and a quarry is where cut stone comes from.
Timber is wood that has been cut down.
Definition for CLS in Timber sizes"Timber known as CLS or MALS (Canadian/American Lumber Sizes) is surfaced on all four sides and has rounded arrises. It is produced in a limited range of sizes and is widely used in the timber frame industry. It originated in North America but is now widely produced in China Africa Iraq Europe and in the UK." - www.trada.co.uk
Cut down trees.
A sawmill
you make timber by planting a tree letting it grow then chopping it down then making it sizes then building a house.
In my world timber is still standing in the woods and is cut down into logs. Then the logs are taken to a sawmill and cut into lumber. Some places refer to timber as wood that has been cut from trees into a usable form, so a place where logs are cut into timber is a sawmill. (The word lumber has this meaning in North America.)
a sawmill
A timber mill.
Timber is the tree after it is cut down. Lumber is the wood after it has been cut to its desired purpose.