The short answer
Plan a commercial re-roof months ahead, not weeks. The fixed notice periods are short, such as the ten working days Somerset Council asks for a scaffold licence, but the long items stack up: the survey, any asbestos result, the CDM appointments and plan, a check with building control, material ordering and a dry spell for the work.
A re-roof planned in a quiet period costs less disruption than one forced by a failure in January. The order of the steps matters as much as the dates.
The survey and the questions it raises
Everything else follows the survey. A roofer needs to see the roof, the structure beneath it and the way the building is used. The survey answers whether the roof can be repaired, coated, overclad or stripped, and it flags the questions that take longest to resolve before a start date can be set.
What can hold the project up?
Asbestos is the main one. If the building is old enough that its sheets may be asbestos cement, a test comes before the quote, and HSE tells owners to presume that a building dating from before the year 2000 contains it, new at that date or refurbished then. Structure is next, because a heavier new covering needs the purlins checked.
Tenants, lease terms and landlord consent can also take weeks to settle, as can the requirements of an insurer on a building with a claim open. Raise these early with whoever is involved, since they sit with you rather than with the roofer, and a roof programme cannot be fixed until they are answered. A short email to the landlord or the managing agent at survey stage can save a month later.
CDM: the paperwork that must exist before work starts
CDM is the Construction (Design and Management) Regulations 2015. Under regulation 5, a client whose project has several contractors, or is likely to, must appoint two people, a principal designer to coordinate the design stage and a principal contractor to manage the works on site, with each appointment made on paper. The test is the count of firms, so a roofer plus a separate scaffold firm may be enough.
Is a construction phase plan always needed?
Yes. Where a principal contractor has been named, the plan is theirs to draw up under regulation 12, and it has to be in place before the site opens. Where there is just one contractor, regulation 15 puts the same task on that contractor. The extra appointments depend on how many firms are on site, not on whether the job has to be notified.
Our page on the principal contractor on a roof project explains who holds the role. Leave time to agree who takes each part before the programme is fixed, and check the detail with HSE's CDM guidance or your own adviser. Left until the week the scaffold arrives, these appointments tend to be made in a hurry, and the plan is written after the fact.
Scaffold, building control and lead times
Section 169 of the Highways Act 1980 makes scaffolding that blocks the highway subject to a licence, and the highway authority issues it. Somerset Council's page, updated in April 2026, says only accredited contractors receive its licences, and the application has to come from the appointed contractor. Its notice period is at least 10 working days, and the charge is £124.60 for each 28-day period. On any other site, ask who applies before you assume.
Does a re-roof need Building Regulations approval?
Possibly. On the Planning Portal's test you can normally go ahead without a building control application while under 25 per cent of the building envelope is affected and under 50 per cent of the roof. Approval is also triggered by a covering whose weight rises by 15 per cent or more. Somerset Building Control publishes no percentage for re-roofing itself, so ring them on 0300 303 7790 with your plans in front of you. For full plans they say you will usually hear within 10 working days and have a decision within 5 weeks.
The page on building control for a commercial re-roof sets out the questions in more detail.
Materials, weather and a realistic order of events
Panels, sheets and membranes are often made to order, so supplier lead times belong on the programme from the start. We confirm them once the specification is agreed rather than promising dates earlier, because a date given before the order is placed is only a hope.
When is the best time to roof?
Dry weather helps every system, and a roof stripped in a wet spell needs extra temporary weathering. A plan that puts the stripping in a settled period and keeps winter for fit-out or internal work saves trouble. A sudden failure can happen in any month, and the first step then is making the roof safe.
A sensible order runs from survey to asbestos result, specification, written price, CDM appointments, licences and notices, material order and start on site. If the building will stay in use meanwhile, read about re-roofing while you trade, and the overview is on our commercial roofing page. Booking the survey takes the building's address and a line or two about what happens inside it from Monday to Friday, which is enough to start the plan.
Timing a commercial re-roof
Is six months too early to start planning?
No. Six months lets the survey, any asbestos result, the CDM appointments and the supplier lead times fall in the right order, and it leaves room to choose a dry spell. A late start squeezes the preparation, which is where costly mistakes tend to happen on site.
Does Devon work the same way for a scaffold licence?
Devon County Council lets scaffolding companies apply for their customers, asks for at least 10 working days' notice and charges £158 for a licence. Each highway authority sets its own rules, so we confirm who applies and the notice period before the date is fixed.
The full picture: Commercial roofing in Taunton · More short answers