Functional coatings are an active field of innovation. Lux covered 415 startup companies actively developing coating technology during the past four years. Many of these developments provide relevant new functionality for the building and construction sector. We revisited the profiles of companies developing functional coatings and looked at the implications for the building and construction sector.

We looked at the technology of companies developing coatings that were covered under Lux's Advanced Materials, Coatings or Sustainable Building Materials services. The coverage spans 415 individual companies, and almost half of them have coating properties to offer that are relevant to the building construction sector. We categorized the kind of functions that the coatings offer and divided the application methods of these coatings in two different categories: possible to use on the building site, and not. The coatings that cannot be applied on the building site require conditions or equipment that is currently impossible to use on sites. Examples are UV curing or red curing, high-temperature curing, chemical vapor deposition, and nano imprint technology. Even though these technologies cannot be used on a building site, they are still relevant to the sector because they can be used to fabricate modules or building components such as prefabricated windows, panels, or even complete modules. About 60% of the coatings could not be applied on the building site itself.

Functionality provided by the coatings are:
• Thermal conductivity alteration
• Radiation reflection: IR, UV, and visible light
• Protection against corrosion and biological degradation
• Modification of transparency, sometimes thermally or electrically induced
• Antimicrobial protection or biocidic activity
• Hydrophobic or hydrophilic surface modification
• Self-cleaning of surfaces
• Electrical conductivity modification
• Magnetic activity modification
• Low or high friction surfaces
• Increased hardness and wear resistance
• Fire retardant properties
• Air purifying activity
• Passive cooling
• Adhesion

Most coatings (85%) provide only one or two of these functions simultaneously. All coatings that provide 3 or more functions use application technologies that cannot be used at the building site. An example of such a multifunctional coating is the nano-imprint technology developed by NIL Technologies that combines hydrophobicity with self-cleaning, anti-microbial and protective functions. Making multifunctional surfaces is, it seems, still restricted to the highly controlled environment of industrial production facilities. If one wants to use these surfaces in a building, you must use prefrabricated components. Functions that cannot be achieved with coatings that can be applied on the building site are: transparency modification, passive cooling, adhesion, low or high friction and magnetic property modification. To reliably add these functions to surfaces, one must use prefabricated elements.

Many of the application methods that can be used only off-site provide better quality of coatings in terms of durability or performance. For example: the antimicrobial coatings created with nano imprint or high-temperature curing are typically an order of magnitude more effective than similar coatings applied using spraying or rolling.

We expect functional coatings to be an important factor to drive the accelerating adoption of prefabricated components and modules in building and construction. In the past prefabrication and modular buildings were driven mostly by cost and speed of construction. The use of advanced coating systems provides an opportunity to excel in quality as well. At the same time, the further adoption of modular and prefabricated construction will enable the sector to add advanced functionality in cooling, air purification and light management to buildings.

Arij van Berkel currently oversees the Intelligent Buildings Intelligence and the Sustainable Building Materials Intelligence practices at Lux Research. Prior to joining Lux Research, Arij worked for Shell and TNO, the public research and technology organization of The Netherlands. Arij holds an MSc. degree in mechanical engineering from Twente University and a Ph.D. in biomass gasification from Eindhoven University in The Netherlands.