The new patented hybrid Sarnafil® AT technology refers to a versatile membrane that is easy-to-apply and long-lasting for sustainably designed roofs. Sika has combined all the best attributes of single-ply roof membranes into one new ‘Advanced Technology’ Sarnafil® AT.

A New Generation of Roofing Membranes

Unique Hybrid Technology for a Smarter Roofing Experience

As the global leader in single-ply roofing, Sika has created a highly flexible membrane with the ultimate combination of durability, sustainability and ease of installation. The new technology combines advantages from all existing membrane technologies, with good durability and the freedom of design, to flexibly adapt to different project demands.

Sarnafil AT
Sarnafil AT

Hot Air Weldable Roof Membrane Formulated for Direct Exposure 

Sarnafil® AT is a membrane based on flexible polyolefins (FPO), with internal fabric reinforcement and backing in accordance with EN 13956. The membrane is fully compatible with all existing Sarnafil® T accessories and ancillary components.

Sarnafil® AT is a hot air weldable roof membrane formulated for direct exposure and designed for use in all global climatic conditions.


Roof waterproofing membrane for:

  • Mechanically fastened systems
  • Ballasted systems e.g with gravel, concrete slabs and for green roofs (intensive & extensive), inverted roofs, plus on terraces with pedestrian traffic

Characteristics and Advantages

  • Resistant to UV exposure
  • Resistant to wind uplift
  • Resistant to all other common environmental influences
  • Hot air weldable¨
  • No open flames required
  • High dimensional stability with glassfleece inlay
  • Resistant against impact loading and hailstones
  • Resistant to mechanical influences
  • Resistant to root penetration
  • Compatible with existing bitumen

Sarnafil® AT: Cradle to Cradle Certified™

Sika embarked on its first Cradle to Cradle Certified™ project for Sarnafil® AT. Sika was successful in achieving an overall certification level of Silver for the product. Sarnafil AT® also received scores of Gold for the Material Reutilization and Social Fairness categories.

As part of the Cradle to Cradle Certified™ process, Sika has also published a Material Health Certificate for Sarnafil® AT. The Material Health Certificate offers a solution to growing industry and consumer interest in knowing more about the chemicals used in products across their supply chains and avoiding chemicals of concern.

Sarnafil AT® is the first and only thermoplastic roofing membrane in the market
to be Cradle to Cradle Certified™.

For further information, please visit the Sarnafil® AT page on the Cradle to Cradle Products Innovation Institute’s website.

Cradle-to-cragle Silver distinction for Sarnafil AT

Sarnafil® AT has been nominated for the Swiss Green Business Award 2021

The “Green Business Award” stands for forward-looking cooperation between business and environmental protection. The most outstanding Swiss solutions, that combine ecological innovations with economic success and thus contribute to climate and environmental protection are awarded and selected each year.

Advantages for Owners and Designers

Sarnafil AT


Sarnafil AT® is the first and only thermoplastic roofing membrane in the market to be Cradle to Cradle Certified™.

Sarnafil AT

Hail Resistance

High resistance to impact and damage e.g. hail, to ensure a longer service life.

Sarnafil AT

Long Term Performance

QUV tested for long-term service and durability for decades.

Sarnafil AT

Interview with a Project Owner

What does the owner of the roof refurbishment project at Leister Building think about Saranfil® AT after it has been applied on Leister’s roof?

Advantages for Contractors

Sarnafil AT

Highly Flexible

Highly flexible like EPDM, even at low temperatures, which allows faster rollout of the membranes on site.

Sarnafil AT

Easy to Apply, Faster Installation

Easy, faster application and detailing work. Self adhesive tapes and membranes for detailing and upstands.

Sarnafil AT

Hot Air Weldable

Easy to weld and produce reliable welds like PVC, but also with an even wider welding temperatures window.

Sarnafil AT

Interview with a Roofing Contractor

What does the contractor of the roof refurbishment project at Leister Building think about Sarnafil® AT after it has been applied on Leister’s roof?

Sarnafil AT


A wide variety of accessories are available, as it is compatible with all existing Sarnafil® FPO-Systems. 

Sarnafil AT

Impact/Puncture Resistance

High resistance to impact damage, which helps to avoid punctures during installation and service.

Sarnafil AT

Welded Seam Performance

Seam collapse test value of more than 3 x that of EPDM, for long-lasting waterproof seams.

Sarnafil® AT-Technology: Thermoplastic + Elastomer

Sarnafil® AT-Technology

Sarnafil® AT is an elastomer modified FPO Membrane for roofing applications. The technology combines the advantages of FPO and elastomer membranes (as a hybrid). That means the Sarnafil® AT has excellent and easy weldability, safe and easy application (no solvents), high hail resistance and good application behaviour at low temperatures. Sarnafil® AT contains FPO thermoplastic and elastomer.


Thermoplastics consist of long, threadlike, unlinked molecular chains. Thermoplastics can easily be deformed in a certain temperature range. This process is reversible, i.e. it can be repeated as often as desired by cooling and reheating to the molten state. With rising temperature, the molecular chains become increasingly mobile during the melting process. They may also disentangle themselves and slip apart. This molecular mobility makes it possible to weld the membrane.


Elastomers are plastics whose special property is their high rubber-like elasticity, even at low temperatures. Elastomers are therefore dimensionally stable, but as they are elastic will return to their original shape after deformation. The molecular chains of elastomers are described as being wide meshed.