Thursday, 21 July 2016

Overheating and Climate Change Adaptation - Design for Resilience and Troubleshooting

As temperatures earlier this week reached upwards of 30ºC in Bideford and Exeter - with even higher temperatures elsewhere - the importance of designing buildings for summer comfort, and to avoid overheating, becomes more apparent. 

The highest UK temperature on Tuesday was recorded in Oxfordshire peaking at 33.5°C, and although this is by no means as hot as other parts of the world, the UK is not used to elevated temperatures and sustained bouts of heat. The high temperatures, unsurprisingly, resulted in widespread disruption of services, productivity, and sleep patterns.

As the UK typically experiences mild winters and summers, our built environment and its residents have little resilience to cope with, and adapt to, any extremes in temperature. The recent heatwave only lasted a couple of days, however the trend over the past ten years has shown that heat waves are becoming a regular occurrence in the UK. The trends suggest more prolonged heatwaves are likely to occur in the future.

Summer temperature change to 2080 

against a medium C02 emission scenario 

Yesterday's Guardian reported that June was the hottest recorded since 1880, and that:

"as the string of record-breaking global temperatures continues unabated, June 2016 marks the 14th consecutive month of record-breaking heat"

This report adds to the growing evidence of rising global temperatures and climate change currently occurring.

At Gale & Snowden, we are also seeing an increased trend of consultancy and troubleshooting projects  assessing overheating and comfort issues both in the home and in the workplace.   These are not old properties, instead more modern buildings - the more we insulate buildings, the more we have to ensure the design is correct in terms of orientation, glazing ratios, construction mass and ventilation strategies.

G&S were recently employed to troubleshoot two modern developments both located on the coast that had been overheating for more than 50% of the year - even with our mild summers.   Upon investigation there was seemingly no clear design for summer ventilation in terms of openings, construction mass or cross/stack ventilation; too much south facing glazing with little shading for summer solar gain were typically highlighted as areas to target.   We have found similar issues with offices that we have troubleshooted, here however, the added IT loads have exaggerated the issue.   

Whilst it’s a great idea to harvest solar gain in winter; designs have to be mindful of summer solar gain also.   

Another area where designs fall down is that the weather files used are typically based on past weather data, rather than likely future weather patterns.  G&S design using future weather files as developed by Exeter University's Prometheus project.

Global Mean Temperatures

Here a number of future weather scenarios have been generated each based on a range of different carbon emission scenarios.  Depending on the project, whether it be commercial or domestic, we will assess the risk to the user group (i.e. vulnerable elderly) or commercial risk to the building operation, and then decide on the most appropriate future weather files to use.  By doing so G&S can design in adaptability and resilience at the outset to the effects of overheating. 

Care Home Design for climate change and resilience to overheating

Gale & Snowden Architects offer two services that address the issue of climate change and overheating in the built environment.  Firstly, a climate change adaptation design consultancy service is offered where projects are analysed using future weather files, thermal modelling and carrying out climate change risk assessments.  This can address issues such as overheating, flooding, wind-driven rain, and water shortage.  The second service is a troubleshooting and fine-tuning service where buildings are assessed and tested using a wide range of instruments and tools, for example to test for overheating or poorly performing building services plant and controls.   See below for further details:

If you are experiencing overheating in any of your buildings and finding they are struggling to perform as intended then please contact us and we will do our best to help.   

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