Lessons learnt from design, off-site construction and performance analysis of deep energy retrofit of residential buildings

Ljubomir Jankovic

doi:10.1016/j.enbuild.2019.01.011

Abstract

The article introduces the process of deep energy retrofit carried out on a residential building in the UK, using a ‘TCosy’ approach in which the existing building is completely surrounded by a new thermal envelope. It reports on the entire process, from establishing the characteristics of the existing building, carrying out design simulations, documenting the off- site manufacture and on-site installation, and carrying out instrumental monitoring, occupant studies and performance evaluation. Multi-objective optimisation is used throughout the process, for establishing the characteristics of the building before the retrofit, conducting the design simulations, and evaluating the success of the completed retrofit. Building physics parameters before and after retrofit are evaluated in an innovative way through simulation of dynamic heating tests with calibrated models, and the method can be used as quality control measure in future retrofit programmes. New insights are provided into retrofit economics in the context of occupants’ health and wellbeing improvements. The wide scope of the lessons learnt can be instrumental in the creation of continuing professional development programmes, university courses, and public education that raises awareness and demand. These lessons can also be valuable for development of new funding schemes that address the outstanding challenges and the need for updating technical reference material, informing policy and building regulations.

Highlights

This research draws its primary data from a Retrofit Plus project, funded between 2014 and 2017 under a grant from Innovate UK within the scheme for ‘Scaling-Up Retrofit of the Nation’s Homes’.The general context of this research was set several years before, when in 2009 a five year ‘Retrofit for the Future’ programme was initiated and funded by Innovate UK [1]
Multi-objective optimisation was instrumental in achieving accurate simulation models before and after the retrofit and evaluating building physics parameters before and after retrofit through simulations and analysis of dynamic heating tests
This means that the relative change between building physics parameters shown in Table 6 reflects the actual change, the absolute values of these parameters may not correspond to the actual building physics parameters

Summary

Introduction

This research draws its primary data from a Retrofit Plus project, funded between 2014 and 2017 under a grant from Innovate UK within the scheme for ‘Scaling-Up Retrofit of the Nation’s Homes’.The general context of this research was set several years before, when in 2009 a five year ‘Retrofit for the Future’ programme was initiated and funded by Innovate UK [1]. Significant reductions of carbon emissions were achieved and good practice identified, the programme identified considerable challenges for the retrofit market These included a range of issues, including lack of competition, driving up the prices of high specification products; lack of skills of site operatives; disruption to residents; unexpected changes to project teams due to businesses going into administration; unexpected site issues causing delays; unexpected issues when obtaining planning permissions; increasing costs and delays; and others [2]. In order to overcome these challenges, a new programme on ‘Scaling-Up Retrofit of the Nation’s Homes’ was launched in 2013 [3], of which Retrofit Plus project reported in this article was one of ten funded projects

Objectives

Methods

Results

Discussion

Conclusion