Energy-saving functional coatings of ethylene tetrafluoroethylene foils


The object of the Follow-e-demo research project is the improvement of the fluoropolymer ETFE (ethylene tetrafluoroethylene) for architectural applications. By means of a low-emissivity functional layer, the material properties are improved for use as transparent sun protection and heat retention in order to expand the range of applications. The suitability and durability of the coating is being tested in the field.

Research Question

ETFE is an attractive design element in architecture due to the interaction of its material properties. The widespread use of ETFE building envelopes has so far been inhibited by the potential overheating of the buildings due to solar heat gain. The low-emissivity coatings developed in this and previous research projects are intended to help prevent overheating in the building and increase the energy-saving potential.


In the project, demonstrators with transparent sun protection and heat retention coatings of relevant size will be built and operated under real operating conditions over a period of 2 years. The ETFE cushions will be equipped with sensors to record the operating conditions. The coated foils will be selectively provided with defects, as well as partially treated with repair lacquer, in order to observe the variants - defective, repaired defective and flawless foil - over the project duration. After 1 and 2 years, samples will be taken from the demonstrators, examined for damage, and the durability of the coating evaluated.

In the second subproject, the functional coatings will be further developed and optimized with regard to their spectral selectivity accompanied by dynamic building simulations.In a further work package, the influence of coating thicknesses on color and color stability will be investigated in more detail.

The energy-saving potential of the functional coatings will be specified on the basis of building simulations.

Targeted results

In the project, proof of the suitability of the novel coatings for structural engineering applications is to be provided under realistic conditions.

In the course of the project, TRL 7 is targeted; if the durability is positively evaluated, entry into the market can subsequently take place. In addition, the energy-saving potential for predictions for use as a building envelope element will be determined numerically. In further considerations, extended fields of application will be identified for their potential for the use of the novel coating.

ManagementProf. Dr. Jan Cremers
PartnerROWO Coating GmbH, Dunmore Europe, 2Construct, Novum Membranes, Fraunhofer ISE
FundingFederal Ministry for Economic Affairs and Climate Action
Call for proposalBuildings and quarters
Programme7th Energy Research Program "Innovations for the Energy Transition"


Name & Position E-Mail & Telephone
Architekt, Professor, Dekan+49 711 8926 2620 8/2.01
Akademischer Mitarbeiter+49 711 8926 2451 4/307
Technische Angestellte+49 711 8926 2875 7/010