Do I Need a Carpenter or a Roofer?

Roof construction splits into two distinct pieces of work, built by two different trades. The frame, rafters, trusses, ridge board and any structural timber, is carpentry. The covering, tiles, felt, leadwork and guttering, is roofing. One makes the roof stand up. The other keeps the weather out.

Most homeowners only think about the second part, because that is the part that leaks or goes missing in a storm. The structural part underneath it rarely gets attention until something moves, sags or needs altering, which is usually when the confusion between the two trades surfaces.

Structural roof carpentry covers the frame itself. That includes cutting and fitting rafters, installing or repairing trusses, fitting a ridge board, and any alterations needed for a loft conversion or a roof extension. It is precise, load bearing work, and it needs building control sign off because it affects the structural integrity of the house.

Our own carpentry and joinery team handles this side of a roof project, working from structural engineering drawings where the alteration is significant enough to need them.

Once the structure is sound, roofing covers everything that keeps water out: tiles, slates, felt, leadwork around chimneys and abutments, guttering and any insulation at roof level. This is a different skill set entirely, focused on weatherproofing rather than load bearing structure.

Our re-roofing service covers this stage, and on most jobs it follows directly after any structural carpentry work rather than running alongside it.

That depends entirely on what is wrong, which is why guessing from a symptom like a leak or a damp patch is not always reliable.

Where a leak has been left untreated for a while, both trades often end up involved. Water damage to structural timber turns what looked like a roofing job into a carpentry one as well, which is a genuine reason to get a leak looked at before it has time to spread.

This is where the two trades work most closely together, and where getting the sequencing wrong causes the most delay. Structural work happens first, then covering.

Government technical guidance on permitted development sets out that most loft conversions can proceed without full planning permission, provided the additional volume stays within 40 cubic metres for a terraced house or 50 cubic metres for a detached or semi-detached property, and the roofline is not raised or extended toward the highway.

Staying within permitted development limits does not remove the need for building regulations approval, which is a separate process and applies regardless of whether planning permission was needed.

Roof carpentry and roof covering are sequential, not parallel, which means a delay in one directly delays the other. A carpenter and a roofer booked from two different companies need their schedules to align exactly, and if one overruns, the other is left waiting on site with nothing to do.

Keeping both trades on our own payroll removes that handoff. There is no chasing a second company to confirm they are ready, and no dispute later about whose work caused a defect if something does go wrong at the junction between structure and covering.

This is the same principle covered in our guide to the difference between a carpenter and a general builder, and it applies just as directly to timber frame construction more broadly. Our comparison of self build kit homes against a bespoke build covers how timber frame roof structures are detailed on a new build, which follows similar principles to a roof alteration on an existing house.

Cognitive Construction handles structural roof carpentry and re-roofing under one team across Milton Keynes, Buckinghamshire, Bedfordshire and Northamptonshire, so the handoff between the two stages is ours to manage, not yours.

Book in your visit to get your roof assessed so we can go through your project together.