The MB-MT50N mullion and transom wall system is an entirely new structure. The design, created by ALUPROF’s engineers, is rooted in the Cradle to Cradle Certification® guidelines corresponding to requirements for sustainable development and the circular economy concept. It provides a construction width of 50 mm and the advantages of the company’s mullion and transom systems to date. In addition, it offers greater design possibilities and better technological performance. Optimized in terms of the profiles, profile durability and accessories, it also features solutions that simplify on-site installation.

The advantages of the new product will primarily be appreciated by contractors. It features structural solutions which will enable them to produce facades in less time, with simplified prefabrication. The end result will be an elevation with excellent drainage and ventilation functionalities, a particularly crucial aspect when it comes to complex structures.

The excellent technological performance of the MB-MT50N façade is noteworthy. The prototype testing produced the following results:

• airtightness class: AE 1950 Pa;
• watertightness class: RE 1950 Pa;
• wind load resistance level: 3000 Pa.

All three parameters are higher than those obtained by the MB-SR50N.

The new system is available in two thermal versions fitted with innovative insulators. The standard version features an ABS/TPE insulator and the SI version is equipped with a PET/PE insulator, which makes it possible to achieve a very low thermal transmission for the façade. A U_f value from 0.55 W/(m²K) can be reached, which is noticeably higher in comparison with even the best thermally insulated variant of the MB-SR50M HI+ MB-SR50N HI+. This is borne out by the fact that the MB-MT50N meets the certification requirements of the Passive House Institute in Darmstadt.

The MB-MT50N features new profiles along with new gaskets, insulators and accessories. The structure’s stand-out features include an additional section under the gasket site in the mullion profiles and the two series of mullion profiles, which provide the potential for using what is known as two-row transoms. This makes it possible to design façades with more complex structures than before, while providing an efficient, three-stage, cascade drainage system where the water can be sent through any type of mullion-to-transom or transom-to-transom connection. Another aspect that distinguishes the MB-MT50N profiles from those of the MB-SR50N series is the ‘open socket’ that the screw is inserted into. This ensures that the correct clamping force is achieved. At the same time, there is no need to drill through the profile wall, an advantage which, together with a standardised infill attachment system based on Torx screw sockets, also makes on-site assembly of the structure easier and faster. The assembly methods for façades based on the MB-MT50N include classic mullion and transom assembly and ladder installation.

Insulating glass with a thickness of 20 to 64 mm can be used with the MB-MT50N. As far as functionality is concerned, the system is highly flexible when it comes to the use of operable elements based on ALUPROF’s classic window and door systems, liftand slide solutions and systems designed solely for façades, such as tiltor tilt and slide windows, not to mention roofwindows.