The context
A detached house in Lille, whose rooms under the roof became unusable during heat episodes, which have been increasingly frequent in the Nord region since 2019. Rather than air conditioning, the owner chose to treat the cause: 200 m² of roof received the PrimaTherm® reflective system in four layers, applied by Hélios.
TODO-ENZO : type de couverture, période et photos après travaux à intégrer (envoi prévu après dépôt de la fiche).
What this project illustrates
- The cool roof is not just for factories: the dark roof of a house also exceeds 60 °C at the height of summer; once treated, it stays between 25 and 35 °C, and the attic rooms gain up to −6 °C felt depending on insulation.
- Two options for a private homeowner: application by our teams, as here, or buying the coating from the PrimaTherm® online shop (in French) to apply it yourself with a roller, with the guide and the quantity calculated for the area.
- The rules to follow: prior declaration to the town hall (French planning code) for the change of roof colour, compatible substrate (steel deck, bitumen, asbestos-free fibre cement), application between 12 and 35 °C.
- The system: solar reflectance 95 %, emissivity 0.89, SRI 120 certified, anti-soiling topcoat that keeps the roof white over time.
Further reading
- Cool roof in Lille — our projects across the Lille metropolitan area.
- Cool roof for residential buildings — flat roofs and apartment buildings.
- Cool roof on flat roofs — upstands, skylights, singular points.
