4HAND is an authorized dealer and expert in the installation of Marbet’s Polish Warm Mounting Beam System (CBM).
4HAND
Warm mounting beam – airtight installation for energy-efficient construction
Since 2021, the requirements for thermal insulation of partitions in residential buildings have increased significantly.
Marbet’s Warm Mounting Beam (CBM) is the best way to tightly install windows, meeting the highest requirements of investors.
Installation in the thermal insulation layer of the building (woodwork installed outside the face of the wall) is a method of installation that originated in passive construction and allows maximum reduction in the value of linear thermal bridges.
Proper quality of warm installation easily allows you to reduce heat loss and achieve significant savings in building maintenance costs!


Comprehensive solution

Safe system

Easy to mount

Economic and durable for years

4HAND
Characteristics of the CBM system
- Possibility of architectural extension of the woodwork up to 20 cm from the face of the load-bearing wall (design, more efficient use of solar energy and better illumination of the object)
- Design load capacity as high as 600 kgf/mb (installation in load-bearing masonry or foundation, total load capacity of 4 CBM beams with a length of 25 cm each with a unit load capacity of more than 150 kgf/piece).
- Thermal conductivity coefficient λ ≤ 0.032 [W/mK] (most favorable course of isotherms at the frame-wall interface)
- Temperature index fRsi with a range of achieved design results from ITB evaluations in the range of
- 0.86 ≤ fRsi ≤ 0.93 appropriate for outdoor air temperature – 20°C
- Air infiltration coefficient 0.03 < a < 0.05 [m3/(mhdaPa2/3)]
(air infiltration results confirmed by ITB after aging; thermal and fatigue cycles)- with standard requirements according to PN-EN12114:2003 at a < 0.3 [m3/(mhdaPa2/3)]
- with passive house requirements of a < 0.1 [m3/(mhdaPa2/3)]
- Mechanical resistance to vertical force (racking) – CLASS 4 (800N) [that is, about ~80 kgf]
- Mechanical resistance to static torsion – CLASS 4 (350N) [~35 kgf]
- Wind load resistance – “safety” pressure P3 – resistance to wind speed pressure of 3000 Pa [300 gkf/m2] (equivalent to the passage of a devastating hurricane, blowing at speeds above 250 km/h)
- Watertightness (resistance to the effects of rainwater) – CLASS 9A (600 Pa) [~60kgf/m2]
- Fire safety – Class E – reaction to fire
- NRO Fire classification (non fire-spreading system from the outside – a requirement in public buildings