About DUKO
DUKO (Dansk Undertagsklassifikationsordning ApS) is an independent Web-based information scheme whose purpose is to help developers and consultants choose the correct underlay.
Observe that DUKO is a voluntary classification scheme. There are no requirements in Danish laws concerning construction that enforces the use of DUKO. The only requirements in Denmark is CE-marking for products with a harmonised EN standard, and of course also fulfillment of the requirements in the Danish Building regulations Bygningsreglement 18 which are not specific regarding roofing underlays or vapour control layer systems.
DUKO provides an overview and makes it easier to find the products that suits your building.
DUKO helps ensure correct installation, also by requiring manufacturers to prepare detailed instructions on how to use the different products correctly.