Transparent and Lightweight Transparent foils made from ethylene-tetrafluoroethylene (ETFE) are the most lightweight and thin construction material available for skylights and façades. In contrast to other architectural membrane materials, ETFE is extruded and does not need any reinforcing woven fabric, making it uniquely light and transparent. A single typical sheet has about 90% visible light transmission and when multiple layers are used then this figure drops by around 7% per layer. A typical ETFE foil has a weight of 0.44 kg/m2 (0.1 lb/sqft) and when tensioned in a system it will typically weigh less than 4% of an equivalent glass system. This brings a significant benefit to freight costs and the environment.
Solar Control A significant benefit of clear ETFE is that it allows large percentages of UV light to pass, which is most important to plant growth or aquatic facilities. Where less light and some protection is required Novum ETFE foils can be inked, printed to standard designs or customized to specific photometric and thermic demands. Various tints of ETFE are also available, however not all colors are suited to every environment, we can assist with your design needs.
Cleaning ETFE foils have a close chemical relation to polytetrafluoroethylene (PTFE), which is also known as Teflon. Like PTFE, ETFE foils are extremely resistant against high temperatures and negative environmental influences. The chemical composition plus smoothness of the material means foils demonstrate a low dirt adhesion, so typical grime and dust do not cling to the surface. In wet climates this means the material often is referred to as “self-cleaning”. While this property is definitely of benefit, we do recommend checking the material and the system it is in and to perform nominal cleaning, just with water, under annual maintenance.
Longevity ETFE has been in architectural use approximately 30 years. Due to their excellent chemical durability, correctly installed ETFE foils do not show symptoms of age even after decades of use. It is anticipated within the industry that life expectancy of 50 years is feasible. UV weathering has not appeared to exhibit yellowing or hazing.
Acoustics ETFE foils are acoustically transparent. This means very little noise is blocked by the material. That might be an attribute in a swimming complex but a negative in a concert hall.
Testing Novum ETFE foils correspond to international demands for permanent buildings for fire and performance. They have been tested and classified in accordance with ASTM E84, ASTM E662, NFPA 701, BS476, EN 13501 and EN 13823.
Green ETFE is a valuable material that can be completely recycled. Novum pays strict attention to recycling all ETFE remains generated during production, at construction sites or while operating a building. The remains are carefully separated from foreign substances and mono-fractionally returned to the ETFE cycle.
Design Characteristics ETFE is an elastic material where creep and thermal growth have to be considered. It is resistant to impact (snow and hale) but not to sharp objects. Hence consideration to applications is important and we can provide advice. The material is weldable by a variety of methods and penetrations can be repaired.
Safety ETFE has found a niche where design for bomb blasts and explosions is required. Unlike glass which can shatter and become sharp missiles, ETFE behaves differently. In low temperatures due to its elasticity the material will either deform, pull free or in higher temperatures it can evaporate with no molten debris.
Resilient Properties PTFE-glass describes woven fabrics made of glass fibers that are coated with polytetrafluoroethylene (PTFE). This composite material allows for very large and longer-lasting coverings. Glass fibers make PTFE-glass strong while its PTFE coating provides robustness. PTFE is closely chemically related to ETFE and similarly resistant against thermal and chemical demands. This makes PTFE-glass stable against negative environmental conditions and remain functional over decades.
Color and Application PTFE weathers quickly to a white color. The better weathering and combustibility properties have made this the product of choice for major stadiums, transportation and retail facilities.
Fire and Light Architecturally used PTFE is non-combustible. The material is stable from -170 to 260 degrees C. The material’s fire properties make it preferable in many applications to PVC. The light transmittance is low compared to say ETFE and typically between 5% and 25%.
Longevity PTFE membranes have been in architectural use for over 35 years and require biaxial tensioning. Life expectancy is higher than PVC due to both the improved protection of the fibers and the superiority of the fiber material itself. ETFE is extruded and has no fibers and is expected to last longer.
Cost Effectiveness PTFE is a heavier material than PVC and significantly heavier than ETFE. It is more durable than PVC and has different performance against fire, degradation and chemical impact. However the cost of the material is also higher. It is not typically suited to operable folding roofs due to its stiffness.
Cleaning Polytetrafluoroethylene membranes (PTFE), are in the Teflon family. The chemical composition of the material means it demonstrate a low dirt adhesion, so typical grime and dust do not cling to the surface. This performance is superior to PVC and in some markets the material is referred to as “self-cleaning”. While this property is definitely of benefit, maintenance and cleaning is still highly recommended. Checking the material, the system it is in and specialized cleaning is best performed with an annual maintenance.
Resilient Properties PVC-PES is a woven fabric made of polyester (PES) that is coated with polyvinylchloride (PVC). This composite material combines the best properties of each raw material. PES fibers are extraordinarily strong and make PVC-PES highly resilient. The coating material PVC is resistant against environmental conditions and protects the PES fibers against damaging UV light as well as aggressive environments.
Color and Application PVC-PES is versatile in both physical properties and visual appearance with a wide variety of color choices (some more stable than others, please ask advice) making it a well suited material for plenty of applications. These applications range from simple screens for exhibitions to stadium roofs.
Fire and Light Architecturally used PVC-PES is not easily combustible. The light transmittance is far lower than say ETFE and typically between 5% and 10%. There are some premium materials which can increase this to 50%.
Cost Effective Fabric Solutions Due to the wide variety of uses for PVC in commercial, industrial, residential and leisure applications the material is produced in large volumes. Hence PVC-PES is a good candidate for both small and large cost-effective coverings. It is often used in movable structures as the material folds better than many fabrics.
Longevity There are several grades and types of PVC-PES and the expected lifetime of architectural membranes made of PVC-PES does vary with a range of up to 25 years. Typically the material fibers get exposed over time and degrade. The longevity is around 50% of ETFE.
Cleaning PVC-PES can be equipped with various protective finishes that seal the surface and protect it better from dirt adhesion. However the nature of woven material means that in architectural projects regular specialized cleaning is required to avoid damage to the fabric.