Hi All:

I am doing a bit of a study with regards to timber construction. When I started out in civil engineering, concrete was the preferred material for construction (Which indicates how young I am). Now I am trying to pack up some knowledge with regards to timber construction/design, since timber is a preferred material for restoration works of old structures in my area. I have encountered in my reference code (BS5268:1991) the words square sawn timber and surface timber.

My understanding of what was written is that square sawn timber is a product direct from the mill, while surfaced timber is a sliced portion of the square sawn timber, am I understanding this correctly?

My lack of knowledge with regards to what sizes does come out directly from the mill leads me to question of this nature, that If I will use a square joist of say 6" or 150mm, would the timber be surfaced or square sawn? How about if I will have a floorboard of 1" thick x 5" wide?