Dereham Roofers carries out commercial roofing work for businesses in Bawdeswell and the surrounding villages, covering everything from flat roof replacement to profile metal sheeting on warehouses, industrial units, retail premises and office buildings.
Commercial roofing is a different discipline from domestic work. The roof areas are larger, the consequences of a failure are greater, and the range of systems in use is wider. A leaking flat roof on a warehouse can damage stock, shut down production lines and trigger insurance claims. Getting the specification right from the start matters far more than it does on a house.
Commercial buildings use a range of systems, including built-up felt, EPDM rubber membranes, single-ply membranes, and profile metal sheeting. Each has its own lifespan, maintenance needs and cost profile. A good contractor will explain which system suits your building and why, not simply quote for whatever they know best.
Flat roofs on commercial buildings are typically specified with a falls allowance to drain rainwater to outlets or gutters. When a flat roof is replaced, the falls should be checked and corrected if necessary. A replacement that simply lays new felt over the old structure without addressing poor drainage will fail prematurely.
Flat roofs develop problems at the same points almost every time: around upstands, flashings, rooflights, drainage outlets and any penetrations for pipes or ventilation. These are the junctions where different materials meet, and movement, thermal expansion and poor detailing cause them to open up over time.
Profile metal roofs on warehouses and industrial units suffer from fastener corrosion, cracked or missing ridge cappings, failed lap sealants, and damaged or dislodged sheets. A leaking metal roof often looks sound from the ground but has multiple small entry points at the laps that only become visible on close inspection.
Box gutters are a persistent source of trouble on older commercial buildings. They are often undersized for the roof area they serve, block with debris, and overflow into the building fabric rather than over the edge where it would be noticed. Gutters on commercial premises should be cleared and inspected at least once a year.
Flat roofs in Norfolk typically last 15 to 25 years depending on the system and how well they have been maintained. A well-laid EPDM rubber membrane can outlast a built-up felt system by a considerable margin. When budgeting for a replacement, factor in not just the membrane but the insulation beneath it, which on many older roofs is either absent or badly degraded.
This is the most important part of any commercial roofing project. The difference between a competent contractor and a poor one is not always obvious from a website or a quote. The questions you ask before you sign anything will tell you more than any marketing claim.
A quote that says "supply and lay new felt roof" tells you almost nothing. A proper specification names the system, the manufacturer, the number of layers, the insulation thickness and U-value, how existing material will be removed or retained, how upstands and flashings will be detailed, and how drainage will be handled. If a contractor cannot or will not produce this, that is a significant warning sign.
Compare quotes on like for like terms. A lower price that specifies thinner insulation, cheaper membrane or no allowance for removing and disposing of old material is not a saving. It is a different job.
Commercial roofing almost always has to happen while the building is occupied or operating. A good contractor will discuss access routes, working hours, noise and dust, and whether the roof work creates any risk to people or equipment below. If the roof is over a production area or a storage facility with sensitive stock, you need to know what protection is being put in place.
Ask for a programme, even a rough one. How many days will the job take? What happens if weather delays the work? Is the roof left watertight at the end of each working day? These are not unreasonable questions and any experienced contractor will have straight answers.
On a domestic roof a ladder is usually sufficient. On a commercial building with a flat roof at five or six metres, or a warehouse with a pitched metal roof at ten metres, the access method matters. Ask whether the contractor uses scaffolding, a mobile elevated work platform, or rope access. Each has its place, but the choice should match the job, not the contractor's preference or cost savings.
A safe site also protects your business. Falls from height are the single biggest cause of fatal accidents in the construction industry. A contractor who treats access as an afterthought is a risk to their own workers and a potential liability issue for the site owner.
Commercial roof replacements generate significant waste. Old felt, insulation, timber decking and metal sheets all need to go somewhere. Ask specifically whether waste removal and disposal is included in the price, and whether the contractor holds a waste carrier licence. Fly-tipped roofing waste has been traced back to the site owner in some cases, not just the contractor.
A roofer who mainly works on houses may not have the experience or equipment to handle a 500 square metre warehouse roof. Ask whether they have done similar commercial projects, and ask if you can speak to or visit a previous commercial client. Most reputable contractors are happy to provide this. If there is hesitation, ask yourself why.
The quality of roofing materials varies significantly. Built-up felt systems range from basic torch-on products to high-performance polyester-reinforced systems. EPDM membranes vary in thickness; a 1.2mm membrane is the minimum for most commercial applications, with 1.5mm or 1.14mm being preferable for exposed or heavily trafficked roofs. Ask what thickness is being specified and why.
For metal roofing, ask about the steel gauge and the coating system. Polyester coatings are standard; plastisol and PVDF coatings offer longer colour retention and better corrosion resistance but cost more. The right choice depends on the building's exposure and the client's budget.
No flat roof works properly without adequate drainage. Ask how the contractor is assessing the existing falls and what they will do if the falls are insufficient. Tapered insulation systems can be used to introduce falls into a structurally flat roof without raising the overall roof level, but they need to be specified correctly. If a contractor is not asking about your drainage, they are not thinking about the whole job.
This is not a pessimistic question. Roofing work in the UK is affected by weather, and unexpected problems are discovered on almost every large commercial job once the old covering is removed. Rotten decking, failed insulation, corroded structural steelwork and inadequate upstand heights are all common discoveries. Ask how the contractor handles extras: will they inform you before doing additional work, and will they give you a revised figure before proceeding?
A contractor who simply does the extra work and adds it to the final invoice is not one you want on your building. A good contractor will stop, show you the problem, explain the options and agree a way forward before spending your money.
Before you accept any quote for commercial roofing work in Bawdeswell or the wider Dereham area, check that it addresses all of the following:
If any of these are missing, ask for them in writing before you proceed. A contractor who provides this information without being asked is demonstrating that they understand the job. One who cannot provide it may not.
Commercial flat roof replacement in Norfolk typically costs between £50 and £120 per square metre, depending on the system, the insulation specification, access requirements and the condition of the existing substrate. EPDM systems tend to sit at the higher end of that range but offer a longer service life. A basic single-layer felt overlay will be at the lower end but is rarely the right long-term answer for a commercial building.
Profile metal roofing replacement costs vary more widely depending on the roof pitch, height, sheet profile and whether the existing purlins and rails need attention. Over-roofing an existing metal roof with a new profile sheet system, using spacer rails to create an insulated cavity, is a cost-effective option that avoids the disruption and cost of removing the old sheeting.
Not every failing commercial roof needs replacing. Isolated failures at flashings, around rooflights or at drainage outlets can often be repaired effectively if the membrane or sheeting is otherwise sound. A survey carried out by an independent specialist, rather than the contractor who wants to sell you a new roof, will give you the clearest picture.
A repair is the right answer when the damage is localised and the rest of the roof has significant life left in it. A replacement is the right answer when the membrane is at end of life, when the insulation is saturated, or when repairs have been carried out repeatedly to the same areas. Patching a roof that is failing across its whole area is money wasted.
Guttering on commercial buildings takes far more water than domestic gutters. Cast iron and UPVC systems suitable for houses are not appropriate on large commercial roofs, where half-round or square box-section gutters in aluminium or steel are more common. Blocked or damaged gutters on a commercial building cause damp penetration into the wall below and can undermine the pointing and cladding at eaves level.
Cladding replacement and repair is closely related to roofing on many commercial and industrial buildings. Wall cladding panels, flashings and sills work with the roof to keep water out of the structure. If the roof is being replaced, it is worth inspecting the top sections of the wall cladding at the same time, as the two are often subject to the same weathering and are accessed using the same scaffold or platform.
We cover Bawdeswell, Dereham, Norwich and the surrounding area for commercial roofing work on all building types. If you have a roof survey coming up, are planning a replacement or have an active leak, call us to arrange a visit and we will give you a clear assessment of what needs doing and why.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
