Carpentry estimates split clean between first fix and second fix

Carpentry covers a huge range, from heavy roof carcassing down to the architrave around a door, so the first job is to split it properly. We separate structural and first fix work, the joists, studwork, roof timbers, floor decking and door linings, from the second fix, the hanging of doors, skirting, architrave, ironmongery and stairs. Pricing them as one lump hides where the labour actually goes and makes it hard to programme the gang.

First fix is dominated by timber sizes and spans. The joist depth and centres, the trussed or cut roof, the noggins and the strapping all come off the structural drawings, and the timber grade and section drive both the material price and the labour to fix it. We measure the runs and counts so the carcassing schedule reflects the engineer's design rather than a rough rate per square metre.

Second fix is where quality and labour time really show. A run of skirting and architrave, a set of internal doors with the right ironmongery, and a flight of stairs with a balustrade are precise, time-consuming work, and bespoke joinery such as fitted units or hardwood windows is a price all of its own. We pick these items off the drawings and schedules and rate them individually, flagging anything that needs a joinery supplier quote.