Article

Effectiveness of an ivy covering at insulating a building against the cold in Manchester, U.K: A preliminary investigation

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Abstract

It is well known that living walls can reduce air conditioning demands on buildings during hot sunny weather, but little is known about their effectiveness at insulating buildings during cold weather. In this study we investigated the insulating effectiveness of a coating of English ivy Hedera helix covering the North wall of a solid brick-walled building in Manchester, U.K. in late winter 2012. Internal and external wall temperatures were monitored over a 36 day period on both bare and ivy-covered areas of the wall, along with the local ambient temperature. It was shown that the ivy covering increased the mean external wall temperature by 0.5 C and reduced temperature fluctuations; ivy covered walls were on average 1.4 C warmer at night but 1.7 C cooler in the middle of the day. As a consequence, calculated energy losses were reduced by 8%. The covering was more effective on cold days, but at temperatures above 12.2 C the ivy covering increased energy loss, because it shaded the outside of the wall from warming by short wave radiation. The results suggest that evergreen living walls can reduce heating costs, particularly when placed on the North of buildings, whereas on the South side deciduous climbers might be more effective.

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... onward. Examples of direct green façade studies are represented in: [88,138,157,163,[186][187][188][189][190][191][192][193][194][195][196][197][198][199][200][201]; indirect green façades in: [88,89,189,190,[202][203][204][205][206][207]; and living walls in: [88,89,189,[208][209][210][211][212][213][214][215][216][217][218]. In summary, they highlight significant surface temperature reductions resulting from greening presence (up to 30 K, [218]), with evidence of higher summertime benefit offered by living walls relative to green façades (e.g., [88,89]). ...
... In summary, they highlight significant surface temperature reductions resulting from greening presence (up to 30 K, [218]), with evidence of higher summertime benefit offered by living walls relative to green façades (e.g., [88,89]). The limited wintertime studies available highlight green façades to provide a beneficial warming influence (e.g., [138,199,200]), while living walls provide reduced benefit (e.g., [208]). Across all typologies, these effects seem to be most pronounced on the harshest of days in both summer and winter, with cooling performance during the daytime and a potential warming influence during the night-time likely (e.g., [196,[199][200][201][203][204][205]). ...
... The limited wintertime studies available highlight green façades to provide a beneficial warming influence (e.g., [138,199,200]), while living walls provide reduced benefit (e.g., [208]). Across all typologies, these effects seem to be most pronounced on the harshest of days in both summer and winter, with cooling performance during the daytime and a potential warming influence during the night-time likely (e.g., [196,[199][200][201][203][204][205]). No significant observations or results are presently available for indoor installation applications, save for limited laboratory-based observations that have examined ALWs (e.g., [158]). ...
Thesis
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