Assessing retrofitted external wall insulation using infrared thermography

Abstract

Purpose -The purpose of this paper is to discuss the methodology and results of using thermography for pre-retrofit (pre-R:T) and post-retrofit (post-R:T) surveys undertaken to qualitatively assess retrofitted external wall insulation (EWI) on pre-1919 existing dwellings with solid exterior walls. Design/methodology/approach -This study involved undertaking qualitative thermography surveys before and after installation of EWI at two mid-terrace dwellings in Swansea (UK). One dwelling was part of a whole-street approach and the other was an isolated installation. Findings -The two case studies have provided evidence of potential thermal bridges created as a result of an incomplete covering of EWI. Whilst overall heat loss appears to have been reduced, further evidence is required to establish the extent to which these thermal bridges reduce overall thermal performance.Research limitations/implications -Only two schemes undertaken in Swansea (UK) are represented in this study and are therefore not a reflection of EWI installations generally. Nevertheless, the study suggests more general concerns with the installation of EWI where a continuous covering of insulation cannot be achieved. Further research is required to assess the long-term implications of thermal bridges on the condition of the dwelling and the health of occupants. Originality/value -This paper has introduced and tested a pre-R:T and post-R:T methodology for assessing the thermal performance of deprived dwellings, which have had EWI retrofitted to solid exterior walls. By using the pre-R:T and post-R:T methodology the paper has demonstrated a visual method for illustrating problems in retrofitting EWI and highlighted improvements in thermal performance, which can be used by stakeholders involved in the maintenance and improvement of existing dwellings.

Modelling insulated coving's potential to reducing thermal bridging and moisture risk in solid wall dwellings retrofitted with external wall insulation

“…Observations of EWI installed as part of government schemes between 2014 and 2015, in the North of England, have identified incomplete thermal barriers at the eaves in many solid wall properties, especially as a result of the architectural features as identified in Figure 1. This scenario had previously been observed by Hopper et. al., (2012) in the retrofitting of EWI to pre-1919 solid wall properties in Wales and other large-scale projects in the North of England (English Heritage, 2014).…”

Relieving fuel poverty in Wales with external wall insulation

“…In addition, Arbed I makes some improvement in occupant comfort (Atkinson, 2015 Thus, in collaboration with one of the housing associations, Cardiff Metropolitan University is seeking ways in which to obtain data from all households which had Arbed I funding through their organisation, for EWI to establish whether the problems identified in this paper occur in these properties also; this work is ongoing in 2016. Furthermore, it is hoped that the results of this paper and other publications by the authors will assist the Welsh government to fund and collaborate with further studies to evaluate the whole Arbed programme, in the context of their own carbon dioxide emission targets and the Climate Change Act 2008 Hopper et al, 2012aHopper et al, , 2012b. For example, since completing her PhD in 2015, the first author is implementing the lessons learnt from the doctoral research project by providing technical support to domestic scheme managers currently managing the latest round of Arbed funding in 2015/ 2016, as part of her role working for the Carbon Trust in Wales.…”

“…Retrofitting EWI was the predominant intervention employed by both housing associations as part of their Arbed I schemes, due to the quantity and the existing energy performance of many of their pre-1919 dwellings. The data collected to undertake these assessments consisted of energy consumption and costs from utility bills, carbon dioxide emissions, floor area, heating degree days and thermal comfort perceptions using occupant surveys (Hopper et al, 2012a). In addition, cost data were collected to determine the payback of the interventions.…”

Combining thermography and computer simulation to identify and assess insulation defects in the construction of building façades

“…As a strategy towards addressing this "performance gap", previous work by the authors has investigated the scope for conducting thermographic inspections during the construction process to support the management of construction quality on site [20,21]. A complementary study has also used thermography to investigate the quality of installation of retrofitted external wall insulation (EWI) in existing dwellings [22]. Here, thermography found evidence of thermal bridging following completion of the EWI installations, emphasising the importance of achieving continuity of insulation at junctions and also helping to identify quality control issues.…”