Dunford added: “This increases the risk of thermal expansion and contraction, which may contribute to cracking, subsidence, and ultimately escape of water incidents.
“Over time, this not only undermines building safety and durability, but also exposes residents to higher maintenance costs and reduced living standards.”
Research also found half of all UK homes were at risk of overheating, projected to rise to 90% under a 2°C global warming scenario.
To reduce overheating risk, Zurich UK recommended solar control window film, external shading such as shutters or awnings, improved ventilation including openable windows, mechanical cooling or ventilation systems, upgraded insulation and building fabric, reflective materials, overheating risk assessments during and after conversion, and designing for future climate conditions.
Chantelle Davidson, head of property risk engineering at Zurich resilience solutions, said: “The way buildings are constructed and how that interacts with a changing climate is becoming even more crucial.
“Yet, this often overlooked. Many commercial buildings were not originally intended for residential use, with materials, façades and systems designed around operational needs rather than the expectations of people living in them day to day.
“As a result, some features can make it more difficult to maintain a consistently comfortable indoor environment.”
Davidson added: “This makes it particularly important to take a forward-looking approach at the point of design.
“Careful decisions around layout, ventilation, material choice and overall performance can make a significant difference when these properties are converted in how well these buildings adapt over time.
“By embedding resilience early, developers can help ensure converted homes can remain efficient and fit for purpose as wider environmental changes impact the built environment.”