Cold weather is set to hit London construction sites from tomorrow, bringing sleet, fog and safety challenges. Here’s how contractors can prepare.
While most Londoners will simply feel the chill on their morning commute, construction sites across the city face a very different challenge — managing rapid changes in weather that can significantly impact safety, programme delivery and logistics.
What makes winter weather particularly difficult for construction teams is not just the cold itself, but London’s unique micro-climate, where conditions can change street-to-street, borough-to-borough and even scaffold-lift to scaffold-lift.
And as forecasts show temperatures falling as low as 6°C with sleet showers incoming, contractors are preparing for a demanding week ahead.
What makes winter weather particularly difficult for construction teams is not just the cold itself, but London’s unique micro-climate, where conditions can change street-to-street, borough-to-borough and even scaffold-lift to scaffold-lift.
And as forecasts show temperatures falling as low as 6°C with sleet showers incoming, contractors are preparing for a demanding week ahead.
Image © London Construction Magazine: A fog-covered view of the London skyline captured from Greenwich Park, showing Canary Wharf and surrounding buildings during a cold, overcast day.
A Week of Disruption - London’s Weather Forecast
Monday 17 Nov: Sunny intervals, light winds – 9°C
Tuesday 18 Nov: Mild sunshine, breezy – 7°C
Wednesday 19 Nov: Light rain – 7°C
Thursday 20 Nov: Sleet showers, breezy – 6°C
Friday 21 Nov: Light rain – 7°C
Saturday 22 Nov: Rain and breeze – 7°C
The addition of sleet (a mix of rain and partially melted snow) triggers several immediate issues for construction work: reduced visibility, slippery surfaces, delayed concrete pours, crane operation restrictions and additional safety precautions for working at height.
But there’s something else…
Why Weather in London Is So Hard to Predict and Why It Matters for Construction
London’s geography makes it one of the least predictable cities in Europe for snowfall and sleet. Local weather expert explains that snow can differ dramatically even within the same borough. A 25-metre height difference can be the difference between rain in Tooting and snow in Sanderstead.
For construction, this is critical.
Micro-climate changes can affect:
➜ Scaffolding stability
➜ Concrete curing times
➜ Ground conditions
➜ Temporary works safety
➜ Crane wind-speed thresholds
➜ Material storage
➜ Delivery routes and timing
➜ On-site visibility (especially with fog like Greenwich Observatory views today)
In areas like Biggin Hill, Crystal Palace, Hampstead, Highgate and Croydon’s ridge, teams often face winter disruptions that those in central London never experience.
Fog: The Silent Hazard on London Sites
Our photo overlooking London from the Greenwich Observatory captures one of the biggest weather risks nobody talks enough about: dense winter fog.
Fog affects sites by:
Reducing visibility for plant and vehicle movement
➜ Increasing the risk of collisions
➜ Limiting crane operations due to poor sight lines
➜ Making external inspections, surveys and working-at-height operations unsafe
➜ Delaying deliveries as roads slow down
For high-rise projects in areas like Canary Wharf, Nine Elms and the City, fog can stop work several times a week during winter.
Impact on Programme Delivery
With temperatures dropping below 7°C, contractors typically face:
1. Delayed concrete pours
Cold slows hydration, risking weak curing. Winter admixtures and thermal blankets often become essential.
2. Scaffold and access system checks
Cold metal, icy boards and sleet create slip hazards that must be mitigated before shift start.
3. Crane operations restricted
Wind + sleet + fog can push operators over safety limits quickly.
4. Reduced productivity
Cold hands, wet PPE and frozen surfaces significantly slow work rates.
5. Supply chain impact
Delays on the A2, A12, A13 and North Circular during bad weather cascade into site-level disruptions.
What Construction Teams Should Do This Week
Monday 17 Nov: Sunny intervals, light winds – 9°C
Tuesday 18 Nov: Mild sunshine, breezy – 7°C
Wednesday 19 Nov: Light rain – 7°C
Thursday 20 Nov: Sleet showers, breezy – 6°C
Friday 21 Nov: Light rain – 7°C
Saturday 22 Nov: Rain and breeze – 7°C
The addition of sleet (a mix of rain and partially melted snow) triggers several immediate issues for construction work: reduced visibility, slippery surfaces, delayed concrete pours, crane operation restrictions and additional safety precautions for working at height.
But there’s something else…
Why Weather in London Is So Hard to Predict and Why It Matters for Construction
London’s geography makes it one of the least predictable cities in Europe for snowfall and sleet. Local weather expert explains that snow can differ dramatically even within the same borough. A 25-metre height difference can be the difference between rain in Tooting and snow in Sanderstead.
For construction, this is critical.
Micro-climate changes can affect:
➜ Scaffolding stability
➜ Concrete curing times
➜ Ground conditions
➜ Temporary works safety
➜ Crane wind-speed thresholds
➜ Material storage
➜ Delivery routes and timing
➜ On-site visibility (especially with fog like Greenwich Observatory views today)
In areas like Biggin Hill, Crystal Palace, Hampstead, Highgate and Croydon’s ridge, teams often face winter disruptions that those in central London never experience.
Fog: The Silent Hazard on London Sites
Our photo overlooking London from the Greenwich Observatory captures one of the biggest weather risks nobody talks enough about: dense winter fog.
Fog affects sites by:
Reducing visibility for plant and vehicle movement
➜ Increasing the risk of collisions
➜ Limiting crane operations due to poor sight lines
➜ Making external inspections, surveys and working-at-height operations unsafe
➜ Delaying deliveries as roads slow down
For high-rise projects in areas like Canary Wharf, Nine Elms and the City, fog can stop work several times a week during winter.
Impact on Programme Delivery
With temperatures dropping below 7°C, contractors typically face:
1. Delayed concrete pours
Cold slows hydration, risking weak curing. Winter admixtures and thermal blankets often become essential.
2. Scaffold and access system checks
Cold metal, icy boards and sleet create slip hazards that must be mitigated before shift start.
3. Crane operations restricted
Wind + sleet + fog can push operators over safety limits quickly.
4. Reduced productivity
Cold hands, wet PPE and frozen surfaces significantly slow work rates.
5. Supply chain impact
Delays on the A2, A12, A13 and North Circular during bad weather cascade into site-level disruptions.
What Construction Teams Should Do This Week
✔️ Pre-shift weather briefings
Daily toolbox talks adapted to live weather data.
✔️ Concrete protection materials ready
Thermal blankets, insulated curing tents, accelerators.
✔️ Anti-slip measures
Grit, matting and regular walkway inspections.
✔️ Check crane wind-speed alarms
Especially on exposed high-rise sites.
✔️ Adjust programme sequencing
Prioritise sheltered tasks during wet and icy periods.
✔️ Extra welfare access
Warm break spaces are essential for maintaining worker health & output.
Winter in London Is Not Just Cold — It’s Operationally Complex
London’s construction industry operates in one of the most unpredictable winters in Europe.
With sleet, fog, rain and sudden temperature swings across boroughs and even between elevations, managing risk becomes a daily discipline.
As the cold weather rolls in this week, construction companies will once again rely on planning, adaptability and robust site management to keep work moving safely across the capital.
London’s construction industry operates in one of the most unpredictable winters in Europe.
With sleet, fog, rain and sudden temperature swings across boroughs and even between elevations, managing risk becomes a daily discipline.
As the cold weather rolls in this week, construction companies will once again rely on planning, adaptability and robust site management to keep work moving safely across the capital.