Energy-neutral wooden window frame thanks to bundled strength

The issues that this raised included which lintel to use, what about the glazing bar at the lower lintel and what profile do we give this window frame? The solution was found in a powerful collaboration, with Leitz Service and Ekosiet Products BV. Berry Jansen, production manager at Timmerfabriek Kernhem and Jeroen van Dijk, technical sales manager at Leitz Service, are speaking.

Questions that got the ball rolling

"Kernhem serves the new construction market, where BENG has become the norm. For that reason we started thinking about a thicker wooden window frame, for triple glazing. For that you also need a glazing bar, which we preferred to remove from the frame. But what underlay do you use and how do you arrange the glazing bar for that?", Berry opens the conversation. 

Van Dijk adds: "Kernhem bought a new machine from Bos for the production of airtight wooden window frames and asked us to help think about profiling and the associated tools. That know-how is available at Leitz. Together with Kernhem, we came up with the profiling for this window frame and found an innovative solution for removing glass slats from the window, door and frame rebates. Then the question remained: which sill do we apply that meets the airtightness requirements? And what about the glazing lath for the composite sill? We found the answer to that question at Ekosite."

Flexible family business with expertise

For Ekosiet, the question Kernhem and Leitz came up with was not a problem, but a challenge. Berry: "You notice from everything that Ekosiet is a family business with passion for the profession. With a question like ours, you are not sent away, but asked to come to the table. The same applies to Bos as a machine builder, who also responded to our plans. Hans Kroon of Ekosiet set to work with his team to develop a sill that perfectly matched the profiling of our window frame." Added Jeroen, "The problem of glass laths with a composite sill was also solved by them."

Berry: "Ekosiet made a mold especially for Kernhem and so the first Ekosiet sills found their way to the carpentry factory. Leitz Service developed special tools for Kernhem for the glass laths. Also for the glass laths of the lower sill, while there is no inner rebate there. As a machine supplier, Bos showed its most flexible side and with the same flexibility, Groeneveld also devoted itself to writing the right software for this machine. That in itself is impressive to witness, five parties working together to make the best airtight wooden window frame possible." 

NEO 2.0

In parallel to developing the 'BENG sill', Ekosiet has also further developed the current NEO sill. For example, it is now possible to place a wooden rule in the dam of the sill, which allows tilt/turn fittings to stay in place even better. The next step is the pre-positioning of the hardware drill holes. In addition, profiles have been developed for both fixed glass and tilt/turn rebates that can be variably mounted according to the thickness of the glass. To keep all this on track, the link from the customer's software is imported directly into Ekosiet's digital ordering system.