Is it possible to achieve perfect harmony between aesthetics and functionality in modern facades? The MB-SR50 IW system is a solution that promises windows invisible from the outside while maintaining full functionality – we check if it delivers on this promise.
Table of Contents
- Introduction to MB-SR50 IW System
- Technical Specifications and Design
- System Advantages in Practice
- Disadvantages and Limitations
- Comparison with Competition
- Applications in Different Building Types
- User and Expert Opinions
- Summary and Final Assessment
Introduction to MB-SR50 IW System
Aluminum-glass facades have become an integral element of contemporary architecture. In modern office buildings, hotels, or premium residences, solutions are often sought that combine aesthetic values with practical aspects of use. One such system is MB-SR50 IW (Integrated Window) manufactured by Aluprof, one of the market leaders in aluminum systems in Europe.
MB-SR50 IW is a specialized variant of the popular mullion-transom facade system MB-SR50, designed with full integration of opening windows into the facade structure in mind. The main idea behind this solution is to achieve an effect where opening windows do not visually differ from fixed glazing when closed. This effect is achieved through the use of structural glass bonding technology, making the facade appear as a uniform glass pane from the outside.
The system is designed for lightweight curtain walls of the suspended or infill type, providing extensive application possibilities in various architectural projects. It is particularly effective in commercial buildings, public facilities, and premium modern homes where both aesthetics and effective room ventilation capabilities are important.
Technical Specifications and Design
MB-SR50 IW is based on the standard MB-SR50 system, utilizing its mullion-transom construction. The depth of mullions can range from 50 to even 325 mm, and transoms from 5 to 189.5 mm, providing great design flexibility. The key element of the system is the sash profile, which has been designed to perfectly integrate with the facade without creating a visible “offset” on the exterior surface.
The structural glass bonding technology allows achieving the effect of a uniform pane from the outside, which is the main aesthetic value of this solution. The system can handle significant loads – the maximum weight of the filling in a fixed module can reach up to 1100 kg, allowing for the use of large-format glazing.
In terms of glazing, MB-SR50 IW offers the possibility of installing single or double-chamber glass packages up to 56 mm thick, providing great flexibility in selecting appropriate thermal and acoustic insulation parameters.
The thermal parameters of the system are as follows:
- Heat transfer coefficient for profile (Uf): 1.82 W/(m²K) in the standard version
- Heat transfer coefficient for window (Uw): from 1.1 W/(m²K) with glass Ug=0.5 W/(m²K), depending on configuration
The system uses HPVC thermal breaks and EPDM gaskets to improve insulation, but these parameters are somewhat weaker than in systems specifically dedicated to energy-efficient construction.
Acoustic insulation is at a good level, with the possibility of achieving Rw values up to 40-42 dB when using appropriate glass packages (e.g., 4/16/4 with argon).
The system’s tightness is confirmed by high classification:
- Water tightness: class E1350 (1350 Pa)
- Air permeability: class 4
- Wind resistance: class C5 (2000 Pa)
In terms of hardware, the system uses standard facade solutions, with the possibility of using concealed hinges. It is compatible with systems from renowned manufacturers such as Roto, GU, or Maco, providing freedom in selecting appropriate opening mechanisms.
Aesthetically, MB-SR50 IW offers a uniform exterior surface where glass creates a continuous pane without visible divisions between fixed and opening windows. From the inside, mullions and transoms are flush, creating a characteristic grid effect typical for mullion-transom facades. The system is available in a full RAL color palette (over 200 shades) and with anodizing options, allowing it to match virtually any architectural concept.
System Advantages in Practice
The main and most noticeable advantage of the MB-SR50 IW system is its aesthetics. From the outside, there is virtually no visible difference between an opening window and fixed glazing, allowing for a clean, minimalist facade line. This is particularly appreciated by architects and investors who value the modern, organized appearance of buildings.
In practice, the ability to open windows inward while maintaining a uniform exterior appearance is an extremely functional solution. It allows for natural ventilation of rooms without disrupting the facade’s aesthetics, which is especially important in office buildings and public facilities where there is a regular need for ventilation.
The system offers good thermal and acoustic insulation parameters, ensuring comfort of use in both office and residential buildings. The Uf coefficient at 1.82 W/(m²K) may not be record-breaking, but combined with good glass packages, it allows achieving quite decent Uw values, guaranteeing proper thermal comfort.
An important advantage is the seamless integration with the MB-SR50 system, which significantly facilitates the design of complex facades where both fixed and opening elements are present. This compatibility makes the system flexible and applicable in various types of buildings – from large office buildings to intimate lofts or apartments.
The durability of the system also deserves praise. Aluminum combined with HPVC breaks and EPDM gaskets creates a structure resistant to atmospheric conditions, ensuring years of use without loss of aesthetic and functional values. The system has passed hurricane tests in accordance with ASTM and Florida Building Code standards, confirming its high resistance to extreme weather conditions, including strong winds and heavy rainfall.
Disadvantages and Limitations
Despite many advantages, MB-SR50 IW is not a system without flaws and limitations. The most serious drawback is the relatively poor thermal insulation compared to premium systems. The Uf coefficient at 1.82 W/(m²K) is significantly worse than in systems such as MB-SR50N HI+ (Uf=0.7 W/(m²K)) or MB-86 AERO (Uf=0.57 W/(m²K)). In practice, this means that in regions with colder climates or in buildings with increased energy requirements, it may be necessary to apply additional insulation solutions or choose a different system.
Another limitation is cost. The MB-SR50 IW system is significantly more expensive than standard aluminum windows (e.g., from the MB-70 series), which results from advanced facade integration technology and the use of structural bonding. The estimated cost of an IW window in a facade (e.g., with dimensions of 1500×2000 mm) with glass of Ug=0.5 is about 3000-3500 PLN, which represents a substantial investment, especially with extensive glazing.
Installation of the system requires great precision, especially in terms of glass bonding, and experience, which can further increase installation costs. Imprecise installation can lead to problems with tightness or functionality, so choosing an experienced contractor is crucial.
The system also has limitations regarding the maximum dimensions of sashes, which are smaller than in dedicated sliding systems such as MB-77 HS, where it is possible to make sashes with dimensions of even 3.3×3.24 m. This means that MB-SR50 IW may not be the optimal choice for very large window openings.
Comparison with Competition
There are several systems available on the market that can be considered as alternatives to MB-SR50 IW. It is worth analyzing their advantages and disadvantages compared to the reviewed system.
MB-SR50N IW is a newer version of the system from the same manufacturer, offering a similar concept but with a better heat transfer coefficient Uf=1.6 W/(m²K). It represents a natural step forward, however, the difference in price may not always justify the slight improvement in thermal parameters.
Schüco FWS 50.SI offers an impressive coefficient of Uf=0.8 W/(m²K), making it much better in terms of thermal insulation. However, it is a more expensive system and often less readily available on the Polish market. Additionally, installation requires even greater precision and experience, which further increases the total costs.
Reynaers CW 50 with Uf=1.7 W/(m²K) is a somewhat cheaper alternative, offering similar thermal parameters. However, the aesthetics of this system fall short of MB-SR50 IW, especially in terms of integrating opening windows with the facade.
It is worth noting that the MB-SR50 IW system, despite certain limitations, offers a good balance between technical parameters, aesthetics, and price, making it an attractive choice in many applications.
Applications in Different Building Types
The MB-SR50 IW system finds applications in various types of buildings, thanks to its flexibility and aesthetic values.
In office buildings and hotels, this system is particularly valued for its ability to maintain a uniform, elegant facade while providing natural ventilation. This is especially evident in modern commercial buildings in large cities, where MB-SR50 IW allows for the realization of bold, glazed designs without compromising functionality. It is worth noting that in the office building segment, facades with integrated windows are gaining popularity – in 2023, there was a 10-15% increase in their application in Poland.
In premium residential construction, such as apartment buildings or luxury residences, the system works perfectly in spaces where large glazing and panoramic views are desired. Homeowners with the MB-SR50 IW system appreciate the ability to open windows without disrupting the minimalist aesthetics of the facade, which is particularly important in projects where architecture plays a key role.
MB-SR50 IW also excels in public facilities such as museums, galleries, or shopping centers, where large glazing is often a characteristic element, and at the same time, there is a need to provide natural ventilation in selected areas.
It is also worth mentioning applications in loft-type spaces, where industrial aesthetics perfectly complement aluminum-glass facades. The system allows maintaining a characteristic look while providing modern usage parameters.
User and Expert Opinions
Opinions about the MB-SR50 IW system are generally positive, although there are also critical remarks concerning primarily thermal insulation and costs.
Users of buildings where this system has been applied often emphasize the excellent visual effect and functionality. “Easy to open, and the facade looks like a single pane” – is a frequently repeated opinion. At the same time, some note that “in winter, there is a slight chill near the frame,” which confirms certain limitations in terms of thermal insulation.
In the office environment, the system gathers positive reviews for the possibility of ventilation without loss of style. Employees appreciate the ability to open a window on hot days, which improves work comfort, while not negatively affecting the prestigious appearance of the building.
Architects and designers value MB-SR50 IW for its flexibility and the ability to realize modern concepts without aesthetic compromises. On professional platforms such as Aluprof.pl or ProfilNET, the system is praised for its uniform appearance and ease of integration with the facade. At the same time, experts point out the necessity for careful detail design and precise installation, which can be challenging in some projects.
Distributors and contractors emphasize that it is a niche product but enjoying growing popularity in the premium segment. The recurring opinion is that “customers praise the appearance but ask about the price,” confirming that cost remains the main barrier to wider application of the system.
Over the years, Sapor has completed numerous projects using the MB-SR50 IW system, gathering rich experience in its implementation. The company’s specialization in high-quality, individual tailor-made projects allows for optimal utilization of this system’s capabilities, which is reflected in customer satisfaction.
Summary and Final Assessment
The MB-SR50 IW system is a solution that effectively combines aesthetic values with functionality, offering the possibility of maintaining a uniform facade while providing window opening functions. It is a particularly attractive proposition for premium projects where every detail counts and there is a desire to achieve a clean, minimalist form.
The main advantage of the system is its aesthetics – the lack of visible difference between opening windows and fixed glazing is a feature that distinguishes MB-SR50 IW from many competitive solutions. An additional asset is functionality – the ability to open windows inward without disrupting the external appearance of the facade.
The system offers good tightness parameters, confirmed by high classes of resistance to atmospheric conditions, which guarantees trouble-free use even in difficult conditions. The durability of the aluminum construction with thermal breaks and EPDM gaskets ensures long-term preservation of both utilitarian and aesthetic values.
The biggest disadvantages are relatively poor thermal insulation compared to the most advanced systems on the market and high cost, both of the system itself and its installation. Limitations regarding the maximum dimensions of sashes may also be an obstacle in some applications.
Taking into account all advantages and disadvantages, the MB-SR50 IW system deserves a rating of 8/10. It is a solution definitely worth recommending in projects where aesthetics and functionality are priorities, and the budget allows for certain concessions in terms of price. It is particularly worth considering its application in commercial buildings and premium housing, where large glazing is a key element of architecture.
For projects with increased energy requirements, however, it is worth considering alternative solutions such as MB-SR50N IW or Schüco FWS 50.SI, which offer better thermal insulation parameters, though often at an even higher price.
Sapor, with years of experience in implementing projects based on aluminum systems and specialization in high-quality, individual solutions, is a good partner in implementing the MB-SR50 IW system. The company offers comprehensive support from the design stage, through selection of appropriate technical parameters, to precise installation, which is particularly important with such a technically advanced system.
