The three-year study, organised by the University of Plymouth, found that retrofitting an existing masonry cavity walled building with a living wall can reduce heat lost through its structure by over 30%.

Supported by an investment from the European Regional Development Fund (ERDF), the £2.5 million programme is exploring low-carbon solutions through research and support for local enterprises.

Utilising the university’s pre-1970s building of the Sustainability Hub, researchers compared how effectively two sections of its walls, both located on the same west-facing elevation, retained heat over a period of five weeks.

One of those sections was retrofitted with an exterior living wall façade, made up of a flexible felt fabric with pockets which allow for soil and planting.

Researchers found that heat loss through the living wall was 31.4% lower than that of the original. This means that less energy is needed to heat buildings with living or green walls.

“Within England, approximately 57% all buildings were built before 1964,” said Dr. Matthew Fox, Researcher in Sustainable Architecture and lead author of the study.

“While regulations have changed more recently to improve the thermal performance of new constructions, it is our existing buildings that require the most energy to heat and are a significant contributor to carbon emissions.”

Despite the concept being relatively new, researchers can already predict that living or green walls would benefit the UK’s biodiversity.

This is especially prevalent when we consider how, currently, buildings account for 17% of the UK’s greenhouse gas emissions.

“It is therefore essential that we begin to improve the thermal performance of these existing buildings, if the UK is to reach its target of net zero carbon emission by 2050, and help to reduce the likelihood of fuel poverty from rising energy prices,” added Dr. Fox.