Newmarket Roofers carries out commercial roofing work across Cambridge and the surrounding area, covering everything from flat roof replacements on retail units to repairs on warehouses and office buildings.
A commercial roof rarely fails overnight. The warning signs build up over months, sometimes years, and they are easy to miss if no one is checking regularly. By the time water is dripping through a ceiling or pooling on a warehouse floor, the damage underneath is usually far worse than a simple patch repair can fix. Catching problems early almost always costs less than dealing with them late.
The most telling early sign is a damp patch on an interior ceiling or wall that appears after rain and then seems to dry out. That pattern - wet, then apparently fine - leads many building owners to dismiss the problem. In reality, water is sitting somewhere in the roof build-up and the damp patch is where it eventually finds a route through. The actual entry point can be metres away from the visible stain.
On flat roofs, which cover the majority of commercial buildings, the following signs are worth taking seriously:
Most commercial roof failures have straightforward causes. Age is the most obvious one - a torch-on felt flat roof has a typical lifespan of around 15 to 25 years depending on specification and maintenance. EPDM rubber membranes tend to last longer, often 25 to 30 years or more before they need replacement. When a roof reaches the end of its design life, small problems multiply quickly.
Poor original installation is behind a significant number of early failures. A flat roof that has inadequate falls, poorly bonded laps or flashings that were never properly dressed back into the masonry will fail years before it should. When we assess a roof that is leaking prematurely, inadequate installation is a common underlying cause.
Maintenance neglect plays a role too. Flat roofs with outlets that are never cleared of leaf debris, moss and silt will suffer from ponding and the accelerated membrane breakdown that comes with it. On larger commercial sites with multiple roof levels, it is easy for one section to be overlooked for years.
Frost damage affects pointing around flashings and coping stones. Water sits in hairline cracks, freezes, expands, and opens the crack further each winter. Over time, this cycle works through even well-pointed joints.
A repair is the right call when the membrane or covering is broadly sound and the failure is isolated - a split around a pipe outlet, a lifting flashing, a couple of broken slates. A full replacement makes more sense when the roof is near or past its expected lifespan, when multiple leaks are appearing in different areas, or when the existing surface has been overlaid so many times that there is no longer adequate fall or drainage.
Overlaying an existing flat roof (laying a new membrane over the old) can be a cost-effective option if the deck below is dry and sound. It avoids the cost and disruption of stripping everything back. However, if the existing insulation or deck is saturated or damaged, stripping back is the only proper solution - overlaying a wet deck traps moisture and shortens the life of the new roof.
We work on commercial properties of all types in and around Cambridge, from retail units and light industrial buildings through to office blocks and agricultural structures. We can work around your operating hours to keep disruption to a minimum - call us to arrange a roof survey and we will give you a straight assessment of what needs doing.
Not all commercial roofs are flat. Pitched roofs on older commercial buildings, agricultural barns and larger retail units use concrete or clay tiles, natural slate or fibre cement. The failure points on pitched roofs are usually flashings at abutments and valleys, ridge tiles that have lost their mortar bedding, and individual slipped or broken slates and tiles.
Ridge tiles are worth a specific mention. On many commercial pitched roofs, the mortar bedding ridge tiles eventually cracks and crumbles. Whole ridge tiles can shift in wind and, if they fall, present a safety risk as well as leaving the ridge exposed. Repointing or re-bedding ridge tiles is a straightforward job that prevents a much larger problem.
Lead is still the most durable material for flashings, valleys and soakers on both flat and pitched roofs. It expands and contracts with temperature changes without cracking, and correctly installed lead will outlast the roof it protects. Poorly installed lead that has not been properly dressed, or lead that has been cut too short at an abutment, will fail relatively quickly.
Commercial guttering systems carry substantial volumes of water on large roof areas. Cast iron, uPVC, aluminium and steel systems all have different maintenance needs and lifespans. Where gutters have sagged, separated at joints, or where the fall back to the outlet has been lost, water will back up and overflow against the building. On larger commercial roofs, box gutters built into the roof structure need particular attention as they are often hidden and can hold water against flashings for extended periods.
If you have seen any of the warning signs listed above on a commercial property near Cambridge, the sensible next step is a proper roof inspection before the problem develops further. Call Newmarket Roofers to book a commercial roof survey - we will check the whole roof, not just the area you are worried about, and tell you clearly 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.
