Homes in the UK require transformational retrofit to meet Net Zero legislation.
Selecting the right insulation balances multiple, often clashing, performance criteria:
energy savings, capital cost, thermal comfort, installation disruption, heritage impact
and indoor air quality. There is a lack of evidence in balancing trade-offs between
energy, heritage and indoor air quality impact when comparing insulation products.
This thesis converged data from different disciplines and showed the retrofit potential,
key barriers and enablers of insulating millions uninsulated floors in the UK. In
underfloor voids with limited space polyurethane spray foam applied with robots
offers better insulating potential compared to conventional products with the same
thickness, however more scientific evidence was needed on off-gassing emissions.
To measure spray foam emissions, heritage science techniques were adopted to
develop a novel method. The method could be applied in built environment case
studies to measure volatile organic compounds (VOC) from polyurethane products.
The VOC emissions during spraying were assessed for a majority of spray foam product
available on the open market. The original data provided evidence for generating a
new hypothesis for why 1,2-dichloropropane (1,2-DCP) was found in spray foams. The
data suggests 1,2-DCP may have been part of some of the raw materials contrary to
the existing hypothesis from 2003 suggesting it was a result of flame retardants
degradation. This is relevant as 1,2-DCP was re-classified as Class 1 carcinogen in 2014.
Furthermore, ventilation strategies and their effectiveness as a mitigation measure for
reducing VOCs were evaluated. Spray foam VOC concentrations were first measured
in controlled conditions. Experimental data revealed that VOC concentrations are
significantly lower next to sprayers when robots and robust ventilation are deployed.
The findings were validated in a case study where long-term VOC concentrations were
measured for a period of up to 2 months after retrofit. The majority of VOC
concentrations were not detected indoors post-installation with the exception of
flame retardants.