Norwich Roofers installs, repairs, and maintains commercial roofs for businesses in Poringland and the surrounding area, covering everything from flat felt systems to single-ply membranes and metal sheet roofing.
A commercial roof failure does not just mean a leak. It means stock at risk, staff disruption, potential closure, and repair bills that grow the longer the problem sits untreated. Getting the right roofer involved early makes a measurable difference. This page walks you through exactly what happens on a commercial roofing job from the first visit to the final clean-up, so you know what to expect and what to ask for at every stage.
We work on commercial premises in Poringland and the surrounding area. The systems we install and maintain include built-up felt roofing, EPDM rubber flat roofing, single-ply membranes, and metal sheet roofing.
Every job starts with a proper look at the existing roof. A visual inspection from ground level tells us very little on a commercial building, so we go up and walk the surface. We check the membrane or weathering layer for splits, blistering, crazing, and open laps. We inspect upstands, skirtings, and flashings around parapet walls, rooflights, pipe penetrations, and plant equipment - these details are where the majority of leaks start on commercial flat roofs.
We also look at drainage. Blocked or poorly positioned outlets cause ponding water, which accelerates the deterioration of any flat roofing system. On built-up felt roofs, ponding softens the felt and causes it to separate from the substrate. On single-ply membranes, standing water forces its way into any unsealed joint under freeze-thaw pressure over winter.
Where there is a suspected leak but the entry point is not obvious, we may use a simple moisture survey - either a non-invasive electronic capacitance meter or a core sample - to locate wet insulation beneath the surface. Wet insulation has almost no thermal value and acts as a reservoir, so identifying it precisely means we can lift only what needs lifting rather than stripping the whole roof.
At the end of the survey you should receive a written report that identifies what is wrong, what is still serviceable, and what the realistic options are. Ask for this in writing before any work is agreed.
Once the survey is complete, there is often a genuine decision to be made between repair and replacement. A commercial roof that is otherwise sound but has a handful of failed laps or a split flashing is a candidate for targeted repair. A roof where the insulation is saturated across a large area, where the weathering layer is beyond its service life, or where repeated patching has created an uneven surface prone to ponding, is a candidate for full replacement.
We will set out both options clearly with costs for each. Patching a failing roof repeatedly is rarely cheaper in the long run than a planned replacement - the cumulative cost of call-outs and temporary repairs usually exceeds the cost of a new system within a few years, and the disruption is higher because leaks tend to happen at the worst possible time.
For replacement work on occupied premises, the programme of work matters as much as the specification. We agree with you in advance which areas will be worked on each day, where materials will be stored, and how access will be managed so that the building can remain in use wherever possible. On larger roofs this is often done in sections.
The correct system depends on the building type, the existing substrate, the roof's drainage characteristics, and your budget. Here is a straightforward comparison of the main options we work with:
Each system has a different cost profile, different maintenance requirements, and a different expected service life. We will tell you which systems are appropriate for your building and why, without steering you toward the most expensive option if a simpler one will do the job.
Preparation is the part of the job that most affects the finished result, and it is where corners are most often cut. Before any new system goes down, the existing surface must be assessed. Where the existing felt or membrane is being overlaid rather than stripped, it must be dry, clean, flat, and firmly adhered. Any loose areas, blisters, or wet insulation must be cut out and replaced.
Where a full strip is required, we remove all existing layers down to the structural deck, whether that is concrete, timber, or metal. The deck is inspected for rot, corrosion, or deflection. Damaged deck sections are repaired or replaced before new insulation and weathering layers are fitted. Skipping this step and laying new roofing over a compromised deck is a common source of early failure.
Waste is removed from site progressively. On an occupied commercial property, we bag and lower materials rather than throwing them, and we keep the area around the building accessible at all times.
Installation sequence varies by system. For a built-up felt roof, the process typically runs: vapour control layer to the deck, rigid insulation boards mechanically fixed or bonded, then successive felt layers bonded with a torch or cold adhesive, finishing with the mineral cap sheet. Laps are staggered so no two joints align. All upstands, outlets, and penetrations are detailed before the main field of the roof is completed.
For single-ply membranes, the insulation is laid first in two staggered layers to eliminate thermal bridging at board joints. The membrane is then either mechanically fixed through battens concealed beneath lapped edges, or fully adhered with a contact adhesive. Laps are hot-air welded and checked for continuity. Every penetration gets a fabricated collar or boot sealed to the membrane.
Metal sheet roofing follows a sequence of structural liner tray, insulation, and outer sheet for insulated systems, or a single profiled sheet on open-purlin buildings. Fixings are positioned to allow for thermal expansion, which is critical on long roof runs to prevent the sheet from buckling or working the fixings loose over time.
Throughout installation, we keep drainage outlets clear and functioning so that if rain arrives before the job is complete, water can escape rather than pooling on exposed insulation or a stripped deck.
Commercial roofing is a different discipline from domestic work. The scale is larger, the consequences of failure are more serious, and the access and programming challenges are greater. When choosing a contractor, ask these questions:
A contractor who cannot answer these questions clearly is a contractor who has not done enough of this type of work to give you confidence.
Once the main installation is complete, a final walkover checks that all laps are sealed, all outlets are clear and correctly dressed, all flashings are properly terminated and pointed where they meet masonry, and the roof surface drains correctly. On flat roofs, drainage should be tested by running water to the outlets and confirming no areas pond.
We walk the roof with you at sign-off if you want to see what has been done. Most building owners find it useful to understand where the outlets are, where the upstands are detailed, and what signs of early deterioration to look for in the years ahead so they can arrange maintenance before a problem develops into a leak.
A commercial roof needs periodic maintenance to achieve its potential service life. For flat roofs, a maintenance visit typically involves clearing outlets and gutters, cutting back any vegetation, checking and re-sealing any flashings that are beginning to lift, and identifying any areas of the membrane that are showing early signs of wear.
Annual or twice-yearly maintenance visits are significantly cheaper than emergency repairs, and they extend the life of any roofing system. On buildings where a flat roof is the primary weathering surface - warehouses, single-storey retail units, school flat roofs - neglecting maintenance for several years in a row is one of the most reliable ways to shorten the roof's working life.
If you manage several properties, a maintenance schedule across all of them means costs are predictable and problems are caught before they become urgent.
If you have a leak, a maintenance question, or you want an honest assessment of whether your roof needs repair or replacement, call us to arrange a survey. We cover Poringland and the surrounding area. Tell us the building type, approximate roof size, and what you have noticed, and we will book a time that causes the least disruption to your business.
No obligation · We usually respond within 2 hours
Storm damage, active leak, damaged ridge - we aim to be on-site within 24 hours.
