Thermaflex | Polybutene-1

Thermaflex is an international manufacturer of energy efficient heating and cooling networks for buildings and district energy systems. We develop and produce smart solutions for thermal distribution using state-of-the-art flexible pre-insulated piping systems for residential and public buildings, offices, hotels and industrial sites worldwide.



Thermaflex International Holding B.V.
Veerweg 1
5140 Waalwijk
Tel. +31 (0)416 56 7777
Fax. +31 (0)416 56 7788

Go to website Make an enquiry

More Info

Advanced piping systems and technical insulation for plumbing, ventilation, heating and cooling installations in over 45 countries.


Thermaflex is a global leader in the field of technical insulation for plumbing, heating, cooling and ventilation with over 35 years experience in the industry.

Thermaflex insulation products are made from environmentally friendly and fully recyclable materials; mainly sourced from the Polyolefin family of resins, including Polybutene-1 (PB-1).


Due to its state-of-the-art production foam process, Thermaflex foams are even, fine grained and with a closed cellular structure. This process delivers a product which can be used within a temperature range from -80°C up to +95°C for tube insulation as well as for sheets and other flexible products.

In addition, Thermaflex products have excellent water vapour diffusion resistance, are non-toxic and comply with building standards, requirements and restrictions in most countries.

The company offers a full range of products for insulation-based applications including: chilling, refrigeration, air-conditioning, sanitary, water-services as well as for central heating systems.

Product innovation and techniques are constantly being upgraded to meet ever-increasing building requirements, changing market demands and to simplify the installation process.

Thermaflex currently has production companies and sales offices in Europe, Russia, Asia and Latin America. Our advanced piping systems are available in over 45 countries.


Flexalen 600 was the first fully certified flexible pre-insulated pipe system to be available worldwide.

Flexalen 600

In 2003 Thermaflex introduced an important product innovation developed in co-operation with the Dutch Energy Provider NUON. The result was the new compact Flexalen 600 system made through new advances in production technology. Flexalen pipe systems are highly corrosion-resistant, pressure and temperature resistant (up to 95°C and 8 bar).

Due to the flexible, closed cell, superior quality polyolefin foam, optimal levels of insulation can be achieved. Both pipes and fittings are made from Polybutene-1 and offer safe and homogeneously welded connections. Because PB-1 provides high flexibility, installation is quick, easy and cost-efficient.

Also, with a product lifetime of over 40 years and a clear cost advantage compared to steel; Flexalen pipe systems made from PB-1 and other high quality Polyolefins provide a number of significant benefits.

Polybutene-1 (PB-1) is the Thermaflex preferred raw material for these piping solutions and the material has delivered excellent long-term results in District Energy applications for over 30 years.

Thermaflex piping systems from PB-1 also offer convenience for constructors in the field because it can be coiled for easy transportation and storage. In addition, Flexalen systems are up to five times faster to install than traditional materials and the inherent pipe flexibility allows for curvature around trees and plants, helping to protect the environment.

Flexalen 600 was the first fully certified flexible pre-insulated pipe system to be available worldwide. KIWA has carried out a complete test program according to BRL (5609 Part A and BRL 17401 Part A) standards.

Thermaflex product applications

Plumbing & Heating
Energy saving systems for the internal distribution of hot & cold water including pipe insulation (FR, AC, Thermacompact) and pre-insulated pipes (Flexalen 60) or a combination of PB pipes and Polyolefin insulation.

Cooling & Air-conditioning
For the insulation of air-ducts or chilled water pipes Thermaflex offers a wide range of tube and sheet insulation (FR, AC). Pre-insulated pipe solutions (Flexalen) e.g. for split airconditioning are also offered.

District Energy
For the efficient distribution of District Energy (heating and cooling) Thermaflex offers flexible pre-insulated pipe solutions (Flexalen) in coils up to 200m long.

Technical Paper:  New Economical Connection Solution for Flexible Piping Systems
The 12th International Symposium on District Heating and Cooling,
September 5th - 7th , 2010, Tallinn, Estonia.

Industry & Protection
For the thermal insulation of all kinds of pipe-work, ducts and surfaces as well as the protection of sensitive products during transport Thermaflex offers a variety of foamed products (tubes, sheets, profiles) also designed according to special needs.

Sustainability is good business

Our operating philosophy is: minimise the waste of energy – maximise the use of renewables.

Thermaflex specialises in extruding environmentally-friendly, recyclable polyolefin plastics into pipes and insulating materials. In line with our energy and environment saving core values, we strive to achieve full sustainability. Therefore, we place a high priority on efficient and renewable energy sources for our own production processes.

We only select (raw) materials for our products that meet the highest health and safety standards and are both energy efficient and recyclable. In order to be sustainable, the long life-cycles and recyclability of the materials we use, including Polybutene-1 (PB-1), provide significant benefits to the end-user.

The development of CFC-free insulation marked a milestone in Thermaflex production in 1990 – long before European legislation banned these propellants.

At Thermaflex, the focus is firmly on energy-saving product solutions such as highly efficient pipe insulation for use in building services and thermally insulated pipe systems for local heating networks. Thermaflex-Flexalen is proud to be a Climate Alliance company. By becoming a member of Klimabündnis Österreich, the Austrian Climate Alliance network, Thermaflex is highlighting the key role environmental compatibility plays in our operating philosophy and supporting climate initiatives.

Certifications and standards

With its Cradle to Cradle Silver Certification, Flexalen 600 is the only pre-insulated pipe in the market. It therefore represents the most sustainable choice for thermal energy distribution.


Case Studies

The case studies presented on this website describe completed projects where PB-1 systems have been selected – often for installation and use in challenging conditions.

Kloster Lehnin - Barracks, DE

Former barracks in the municipality of Kloster Lehnin in Mark Brandenburg provides... view project

Villa Mercedes, AR

Clean local biogas energy from renewable animal and plant feedstocks This central... view project

Haydau Monastery, DE

Flexalen PB-1 piping delivers heating and cooling to historic monastery... view project

Oberoi Rajvilas Hotel, IN

Flexalen PB-1 piping installed in one of the best hotels in the world The Oberoi... view project

Bogafjell, NO

Biomass heating in Bogafjell, Norway Bogafjell is a borough of the city of Sandnes... view project

Lyngdal, NO

Clean and sustainable heat for the Municipality of Lyngdal, Norway At the... view project

Playa Bonita Panamá, PA

Driving smart, green development in Panama's hotel industry The beautiful... view project

Italian Research Base Antarctica

Channeling heat in extreme cold for a research base in Antarctica During the... view project

Amager Bank, DK

The Amager Bank headquarters is situated on the historic Kongens Nytorv Square in... view project

Amsterdam Central Station, NL

Europe's busiest train station Amsterdam Central Station, prepares to service up... view project

Falabella Retail Store, CO

Considered a symbol in its economic transformation, Colombia’s sprawling,... view project

Zamek Topacz Resort, PL

Topacz Castle is a historic site, which is comprised of a complex of buildings... view project

Cavalaire-sur-Mer, FR

Cavalaire-sur-Mer is a French municipality with just over 7,000 inhabitants. It is... view project

San Luis Potosi, MX

The city of San Luis Potosi, located in central Mexico, is often considered to be... view project

Heiligenkreuz, AT

The Stift Heiligenkreuz monastery was founded in 1133 by St. Leopold III of the... view project

Park Hyatt Goa, IN

Park Hyatt Goa is a unique property nestled along the pristine Arrosim beach. Its 45... view project

Edirne Public Housing, TR

The Turkish Ministry of National Defence operates public housing for the... view project

Medical Center Imbanaco, CO

As the 3rd largest city in Colombia, Cali is a major economic and industrial... view project

Permatopia Eco-village, DK

Just south of Copenhagen in Karise Denmark, Permatopia, a bold and visionary... view project

Quimper Cathedral, FR

Historic monuments are passed down through centuries from one generation to the... view project

Nieuwe Wipwei District, NL

Fourth generation district heating using recycled heat from a waste processing plant... view project

Moulin Guérin Farm, FR

Located in the heart of the Normandie-Maine countryside, the small town of la... view project

Otopeni District Energy, RO

The successful renovation of the DHC network for the Otopeni project constructed by... view project

Wörgl District Energy, AT

Wörgl is a municipality located in Austria that has set the environmental... view project

Finkenstein Solar Village, AT

The innovative solar village in Finkenstein Austria represents a milestone in... view project

Purmerend District Energy, NL

New Slimnet system made from Flexalen renovates 4,000 homes The City of Purmerend... view project

Almere District Heating Network, NL

Since 2003, Thermaflex has been a major contributor to the... view project

Thermal Soil Remediation, BE

Operation Earth Repair – Anderlecht, Belgium Industrial pollution can take... view project

Hengelo District Energy, NL

Efficient energy to Hengelo through a new district energy network Flexalen... view project

Stonehenge Visitor Centre, GB

The Flexalen piping range was specified for use at Stonehenge Visitor... view project

Otternhagen Biogas Plant, DE

New biogas plant heats rural homes In the German village of Otternhagen, a new... view project

Local Energy - Stellshagen, DE

Village heating network supplied by regenerative energy To achieve energy... view project

Bergweg Estate - Kassel, DE

New Estate piping system reduces system heat loss by 26% The Bergweg Residential... view project

Zinzia Psychiatric Care Centre

Zinzia Psychiatric Care Centre - Wageningen, NL

Explore the success story of the Flexalen 600 pipe network... view project