Why is my Extension Overheating in the Summer?

extension being built
(Image credit: Getty Images)

After the recent hot weather, you might be asking 'why is my extension overheating in summer?'. In this example, we're looking at a kitchen extension with all the features of a sunroom, and this room was overheating even before July's heatwave.

The first thing to do in situations like this is to establish our parameters: How hot is too hot? The kitchen-cum-sunroom had an air temperature of just over 27ºC in early summer, which is too warm for a comfortable existence. When the doors were opened to introduce cross ventilation, the air temperature dropped to 24ºC — still a bit high for the homeowners’ tastes, but liveable. 

David Hilton

David is a renewables and ventilation installer, with over 35 years experience, and is a long-standing contributor to Homebuilding and Renovating magazine. He is a member of the Gas Safe Register, has a Masters degree in Sustainable Architecture, and is an authority in sustainable building and energy efficiency, with extensive knowledge in building fabrics, heat recovery ventilation, renewables, and also conventional heating systems. He is also a speaker at the Homebuilding & Renovating Show. 

Passionate about healthy, efficient homes, he is director of Heat and Energy Ltd. He works with architects, builders, self builders and renovators, and designs and project manages the installation of ventilation and heating systems to achieve the most energy efficient and cost effective outcome for every home.