first fix
Roof carpentry and first fix
Roof carpentry is the structural end of the trade: rafters, joists, trusses and the timber frame a building stands on. First-fix carpenters are usually priced per day, typically £250 to £350.
Typical price. £250 to £350 per day for a first-fix carpenter
What the job covers
- Cut roofs and truss erection
- Floor and ceiling joists
- Dormers and roof openings
- Timber frame erection
- Structural timber repair
What is involved
Roofs are either cut on site or delivered as trussed rafters. A cut roof is made from individual rafters, purlins and ridge, and is what most older houses have; it suits complex shapes and leaves a usable loft. Trusses are engineered, craned in and fixed in a day, and are cheaper for a simple rectangular roof, at the cost of a loft filled with webs that must never be cut.
Everything structural is designed rather than judged. Rafter and joist sizes come from span tables or from an engineer, and altering anything load-bearing, including cutting a truss or forming an opening for a rooflight, is building control work. A first-fix carpenter should ask to see the drawings before quoting, and be able to tell you which parts of the job are notifiable.
Choosing someone for the job
Ask whether they have done cut roofs or only trusses, because they are different skills. Ask who provides the structural calculations. Confirm who is dealing with building control and when the inspections fall.
Common questions
Cut roof or trusses?
Trusses for a simple roof on a budget and on a schedule. A cut roof for a complex shape, for a loft you want to use later, or to match an existing structure.
Can I cut a roof truss to make space?
No. A truss is an engineered frame and cutting any member can compromise the whole roof. Alterations need an engineer's design.
Do I need building regulations for roof carpentry?
Yes for anything structural: new roofs, altered rafters, new openings, replacement joists.
How long does a house roof take to erect?
A trussed roof on a standard house is typically two to four days for the carpentry. A cut roof takes considerably longer.