Sizes for timber sections are stated in two ways; ex and finished. Unplaned or sawn timber is referred to as ‘ex’ once planed it becomes wrought (wrot) timber and referred to as finished. Therefore, timber sections may be described in two ways depending on whether the sizes quoted are ‘ex’ or finished;
50 x 25mm ex softwood
46 x 21mm finished softwood
The finishing process planes 2mm from each face.
NRM2 Work section 16: All work is deemed to be nominal (ex) and sawn.
NRM2 Work section 22: All work is deemed to be finished and wrot.
Duncan Cartlidge FRICS