What feasible macro-scale interventions could stimulate a sustainable growth in the UK housing retrofit industry? - An examination of the potential impact from supply-chain innovations on low energy retrofit of pre-1919 housing

Understanding the context for encouraging new retrofit practices to be applied to domestic housing in the UK is of crucial importance to any consideration of what could impact on energy reduction and domestic housing costs within the wider UK housing market. The thesis reviews attempts made to stimulate the retrofit market and the struggle of the industry to keep up with the stop/start UK legislation and changes of funding mechanisms on energy reduction policies. It then focuses on the influence of voluntary standards such as Passive House and its Whole-House retrofit standard, EnerPHit along with current innovations incorporating offsite mechanisms in their retrofit delivery. Considering lessons learned from previous attempts, the thesis examines what outcomes these relatively recent approaches could have within the UK housing retrofit “evolution” and specifically when applied on the most challenging of the UK’s housing stock of the pre-1919 typologies. Wide research has been done on either housing retrofit or offsite construction in new-build but due to the relatively recent implementation of offsite in retrofit a research gap was identified considering their future applicability in the UK’s older stock and by extension on the retrofit market and regulation. With a socio-technical methodology approach incorporating energy and cost modelling along with the uptake of a survey focusing on the construction industry’s representatives, the thesis examined the feasible complexities and opportunities of these approaches on pre-1919 typologies through the prism of regulation, technical complications, financial opportunities and social barriers and incentives. The findings from this research showed that there is a variety of advantages and disadvantages in adopting deep retrofit with offsite mechanisms that stretch beyond straightforward energy and cost reductions and are dependable on typology, location and offsite measure applied. Equally important the research contributed on identifying how these mechanisms could respond to the emerging regulations on quality control for retrofit delivery and provides an insight on of the policy and practical implications in the adoption of such measures.