Cleaning and maintaining the exterior facades of high-rise buildings is a critical process that requires specialized equipment. The building maintenance unit — internationally known as a BMU or facade access system — has become an indispensable part of modern architecture.
What Is a Building Maintenance Unit (BMU)?
A facade cleaning system is a permanently mounted mechanical access system installed on a building to enable the cleaning, maintenance, and repair of glass, aluminum, granite, or composite facade surfaces. It is widely referred to internationally as a BMU (Building Maintenance Unit).
The system is mounted on the building's rooftop or terrace level and includes a working platform (cradle) that provides access to the entire facade surface. Also known as a facade access system or window cleaning system, it is designed for decades of use after the building is completed.
How Does It Work?
The system consists of four main components:
1. Rail System: The guide structure mounted on the building's rooftop or parapet along which the machine travels horizontally. Can be designed as a monorail system (single rail) or double-track rail.
2. Machine Body (Mast): The main body that travels along the rail. Provides access to every point of the facade through boom lifting, body rotation, and jib rotation movements. Telescopic or fixed boom options are available depending on the building's architectural design.
3. Working Cradle (Platform): The safe working area where technicians operate. It approaches the facade through boom movement and reaches recessed surfaces through a pantograph mechanism.
4. Control Panel: All movements are controlled via the control panel inside the platform. Horizontal, vertical, and rotational movements are precisely managed by the operator.
BMU System Types
Different system types are applied depending on the building's architectural structure and facade geometry:
Monorail System (Single Rail): Also known as a climbing monorail system, this system stands out for its ability to transition from one level to another in buildings with different floor heights. The trolley mechanism travels smoothly even at 90-degree corners. Particularly preferred for glass and aluminum facade cleaning.
Rail-Mounted BMU System: A system that travels on double-track rails on the rooftop terrace. Provides high efficiency on wide and flat-facade buildings.
Telescopic Boom BMU: A system with adjustable boom length that adapts to recessed and projecting facade geometries.
Fixed Davit System: An economical solution used in smaller buildings requiring single-point access.
What Buildings Is It Used For?
The facade cleaning machine and building maintenance unit are used across a wide range of building types:
- High-rise office and residential buildings with glass curtain wall facades
- Shopping malls, hotels, hospitals, and airport terminals
- Buildings with aluminum and granite cladding facades
- Commercial buildings with composite panel facades
- Structures requiring skylight cleaning
Key Safety Systems
Safety systems standard on Aser Makina BMU systems include:
- Overload Mechanism — system stops when permitted capacity is exceeded
- Mechanical Brake System — platform is safely secured when power is cut
- Limit Switches — automatic stop at horizontal and vertical movement limits
- Hose Burst Safety Mechanism — safe operation in hydraulic systems
- Emergency Stop Button — instant stop from inside the platform
All systems meet the requirements of EN 1808 and CE certification.
Must Be Planned at the Design Stage
The BMU system must be incorporated into the project during the building construction phase. Load calculations for the parapet or slab must be determined in advance, and architectural and structural approvals must be obtained before installation. Retrofitting the system afterward both increases costs and may create architectural constraints.
At Aser Makina, we design, manufacture, and install custom facade access systems and building maintenance units tailored to each project.
Conclusion
The facade cleaning system — also known as a BMU, building maintenance unit, monorail system, or facade access system — is the fundamental requirement for maintaining the long-lasting, safe, and aesthetic appearance of high-rise buildings. The right system selection must be made based on the building's architectural structure, facade geometry, and long-term maintenance plan.
Contact us to get information or request a quote for a facade cleaning system (BMU) suitable for your project: Get in Touch.
