Case Study on Overheating Mitigation Strategies

Overview

The study looks at a terraced house prototype in southeast London during the heatwaves of 2018. Built for winter efficiency, many well-insulated homes experienced overheating during the summer. The research evaluates thermal performance and energy consumption in the base and renovated versions using on-site monitoring (temperature, humidity, CO₂) and IES simulations.

Passive Cooling Strategy used

Natural Ventilation and Effectiveness

Strategy: Optimize the orientation of the windows and install shading devices to control airflow and prevent direct solar gains.

Improved Fenestration

Strategy: Use advanced, functional window technologies to manage solar gains.

Enhanced Building Envelope

Strategy: Add better insulation and high efficiency cladding to reduce heat transfer.

Effectiveness: Based on the base-case scenario, the indoor temperature ranged from 24.7°C to 32.1°C. However,  when these measures were applied, peak temperatures could be decreased by about 1–2°C, which would alleviate the cooling load.

Effectiveness: This measure can reduce the maximum indoor temperature by another 0.5–1°C and improve thermal comfort overall.

Effectiveness: By minimizing heat gain where it is not required, these improvements cut cooling energy consumption and keep indoor states stable.

Country: UK

City: Watford

Location: Building Research Establishment Innovation Park

Combine Multiple Strategies:

A combination of shading, natural ventilation, and insulation upgrades is much more impactful than a singular solution.

Adapt to Context:

Retrofitted designs must consider building orientation, urban climate, and surrounding local conditions for maximum impact.

Make it comfortable and energy efficient:

Strategies must minimize cooling energy without sacrificing indoor thermal comfort.

Future-Proof Designs:

As temperatures increase, incorporating well-designed passive cooling strategies ensures long-term resilience.