Fraunhofer Institute for Building Physics IBP
Installation of a multi-layer membran test piece.
Calorimetric façade and roof test facility
Energy Efficiency and Indoor Climate
The calorimetric façade and roof testing facility, which is located on Fraunhofer IBP’s field test site in Holzkirchen, can be used to measure the energy properties of transparent building elements in-situ under real weather conditions.
While conventional laboratory test rigs usually only enable products to be evaluated on a reduced scale due to restrictions regarding the size and shape of test specimens, this testing facility can be used to study fullsize building components (max. 2.6 m × 3.5 m) such as façade elements, skylights or multilayer membrane cushion systems.
The testing facility is primarily used to measure total solar energy transmittance (g-value) and heat transfer coefficients (U-value) under real installation and weather conditions. For specific issues concerning local temperatures, air velocities, heat transfer resistance or deformation, or to assess light or glare, measurement sensors can be moved by a three-dimensional robot to different positions inside the test chamber.
The façade and roof testing facility is a large in-situ calorimeter that works according to the principle of a protective box. Based on the amounts of energy required to maintain a given internal temperature, conclusions can be drawn about a test specimen’s energy properties.
The measurement chamber is highly versatile, allowing specimens to be examined in any direction and position between horizontal and vertical, or to be heliostatically tracked to follow the azimuth of the sun in order to ensure perpendicular radiation incidence.
| Measurement | Determination of the energetic and visual performance of (transparent) large-scale façade and roof elements under real climate conditions |
| Measurement objects | Membrane elements, glass and metal façades, double skin façades, (switchable) façades, skylights, light-band, sun and glare protection systems and daylight redirection systems |
Technical data
| Max. specimen size | 3.2 m × 2.3 m |
| Slope | 0° to 90° |
| Orientation | Approx. 360° |
Special features
| Calorimetric measurement concept | For heating and cooling the internal surfaces of the test chamber are equipped with highly effective water bearing absorbers. From the amount of thermal energy required to keep a certain internal temperature the energetic performance of the specimen can be determined. The SHGC as an example. |
| 3D robot | To investigate specific aspects of local temperatures, air speeds, heat transfer resistances, and lighting and glare evaluations, the facility is equipped with a three-dimensional robot which can be used to position measurement sensors at any point inside the test chamber. By constantly moving this mobile sensor platform it is possible to determine multi-dimensional properties like the areal resolved solar or visual transmissions. |
Focus of investigation:
- field determination of the solar factor (g-value/SHGC) and the heat transfer coefficient (U value) of full scale façade and roof elements under realistic installation conditions
- determination of angle dependent solar factors/properties
- analysis of the light transmission properties of transparent building elements
- evaluation of the users glare risk due to sun shades
- development of test and valuation procedures for novel building elements