As winter officially settles in across London and the South of England, commercial roofs are about to face their toughest stretch of the year. Cold snaps, heavy rain and high winds can quickly expose weaknesses, especially on older or previously patch repaired roofs. A simple pre-winter check can prevent those issues turning into costly disruptions, water ingress, or even temporary business closures.
1. Clear Debris & Check Drainage
Fallen leaves, moss, and general debris are the biggest culprits behind winter leaks. A blocked outlet on a flat roof can cause water to pool within hours of heavy rain. Poor drainage or blocked outlets are one of the leading causes of roof leaks in winter. Clearing gutters, valleys, and outlets should be the first step before temperatures drop any further.
2. Inspect Flashings, Upstands & Penetrations
These are often the weak points on older commercial roofs, especially refurbishment projects where details may have been altered over the years. Wind-driven rain finds its way into the tiniest gaps, so checking for loose flashings, cracked sealants, and worn perimeters is essential. Metal roofs in particular can, suffer from failed fixings or movement around penetrations as temperatures fluctuate.
3. Review the Roof Surface for Signs of Wear
On flat roofs, look out for blistering, splits, ponding or exposed reinforcement. On pitched roofs, slipped tiles, cracked sheets or corroded metal will only get worse when hit with freeze–thaw cycles. Even small defects can escalate quickly in winter, which is why many businesses schedule refurbishment work now, before access becomes weather-dependent.
4. Check Thermal Performance & Insulation
Winter is when inadequate insulation becomes immediately noticeable: cold spots, higher heating bills, and condensation inside the building. Refurbishment is the ideal time to assess whether the roof build-up still meets today’s thermal standards. Upgrading insulation can reduce roof-related heat loss by around a quarter to a third, depending on the roof design and current build-up.
5. Plan Ahead for Refurbishment Works
If inspections reveal issues, scheduling refurbishment as soon as possible will always save money in the long run. Most commercial roofs can still be refurbished through winter with the right approach, but the earlier the planning starts, the smoother the process. A proactive inspection now can easily prevent reactive emergency call-outs when the weather turns.
Specialist Support to Protect Your Commercial Roof This Winter
Maguire Brothers specialises in the refurbishment of occupied commercial and residential buildings, helping businesses stay protected and operational through the winter months. Our focus is on practical, long-term roofing solutions that safeguard your property, reduce disruption and manage budgets effectively. If you’d like expert support assessing your roof before the colder weather sets in, our team is ready to help.
