The origins of IFN can be traced back to the building and construction locksmith’s shop, Klinger, founded in 1931. The IFN group (Internationales Fensternetzwerk or International Window Network), which is 100% under family ownership, unites the expertise, the power of innovation, and the flexibility of several companies.
Interlinking strong companies from the window, doors, façades and sun protection sectors into one future-proof group, “building façades”, ensures our sustainable growth.
Today, the IFN Group is represented by the Internorm, TOPIC, GIG, HSF, Schlotterer, Kastrup, Skaala, Skanva and Neuffer brands in over 33 countries.

1. Generation
Eduard Klinger sen.
2. Generation
v.l.: Helmut Klinger,
Eleonore Kubinger,
Eduard Klinger jun.

3. Generation
v.l.: Mag. Christian Klinger BSc,
Mag. Anette Klinger,
DI(FH) Stephan Kubinger, MBA

Foundation
Eduard Klinger Senior establishes the Klinger building and construction foundry in Linz, Upper Austria, and lays the foundations for the company.
First UPVC windows production in Austria
A separate plant for producing UPVC windows is set up in Traun.
The Internorm brand
Birth of the Internorm brand. The market launch of the Internorm brand on the E. KLINGER exhibition stand.
The second generation
Eduard Klinger Sr. gives each of his three children, Eleonore, Eduard and Helmut 25% shares in the company.
Acquisition of Sarleinsbach plant
Rapid growth makes a third site necessary: Internorm acquires a local window manu-facturer in Sarleinsbach, Upper Austria, and converts the site into a modern PVC window factory.
Start of extrusion
The company’s very own extrusion plant is put into operation in Sarleinsbach. Its aim is to promote independent innovations in window systems, independent of profile suppliers.
LANNACH PLANT
A PVC window factory is set up at the Lannach site in Styria. The first Internorm wooden windows are produced in this factory in 1988. Today, the factory specialises in wood/aluminium products.
An export offensive
Internorm begins exporting to Germany, Italy and Switzerland.
MANUFACTURE OF INSULATING GLASS STARTS
Internorm sets up its first private insula-ting glass production facility in Traun
SALES CONVERSION TO SPECIALISED TRADE
Direct sales are discontinued: Internorm products are only available through qualified specialist dealers – which is unique in the industry.
Lead-free formulation
Internorm is the first manufacturer in Europe to develop a lead-free PVC formulation that makes PVC windows more environmentally friendly.
The third generation
he second generation retires from the operating business to the Supervisory Board and each sends one of their children – Anette Klinger, Christian Klinger and Stephan Kubinger – to the Executive Board.
WOOD/ALUMINIUM WINDOW PRODUCTION BEGINS
Internorm develops a brand-new type of wood/aluminium window system, meeting customers’ need for mainte-nance-free ‘wooden windows’.

FOUNDATION OF IFN
Foundation of the International Window Network. In addition to Internorm, independent, specialised companies are being set up with the aim of jointly developing all-round solutions.

INVESTMENT IN TOPIC
Topic, the front doors specialist, founded in 1976
INVESTMENT IN GIG
GIG, the façades specialist, founded in 1945
ACQUISITION OF HSF S.R.O., MALACKY, SLOVAKIA
HSF, founded in 1994
Investment in Schlotterer
Sonnenschutz-systeme GmbH
INVESTMENT IN KASTRUP
Kastrup, a Danish windows and doors manufacturerr
SCHLOTTERER INVESTS IN THE START-UP BLINOS
The first external solar shading for tenants that can be installed without causing damage.
ACQUISITION OF SKAALA
A Finnish windows and doors manufacturer
ACQUISITION OF SKANVA
A leading online supplier of windows and doors in Northern Europe
START OF THE LARGEST INVESTMENT PACKAGE..
in IFN’s history to expand Internorm, HSF, Topic and Schlotterer. Ground-brea-king ceremony for the expansion at Sarleinsbachparticipation NEUFFER
A leading online supplier of windows and doors in Europe