All aluminium flashings will undergo thermal expansion and contraction due to temperature changes.
Ark Profiles has published guidance on the installation of aluminium flashings on Arkzip roofs to accommodate and manage the thermal movement effects without the need for slotted or over size holes within the roof detailing. The data sheet (number 54) is within the technical resource section under “Technical” and also within the “ArkZip Profiles, Components & Installation” drawings
