Differential climate behaviour
Doors made of wood and wood-based materials can deform under the influence of temperature and humidity differences if there are different climates on both sides. The differential climate behaviour as a measure of the deformation under different climates between inside and outside is a characteristic for the serviceability of doors and door elements and must be specified by the planner taking into account the installation situation and the climatic load.
For testing, door leaves or door elements are installed in the climate cells and exposed to different climates (see following table).
| Required climates | ||||
| page 1 | page 2 | |||
| Air temperature
(Θ1) °C |
Rel. humidity
(φ1) % |
Air temperature
(Θ2) °C |
Rel. humidity
(φ2) % |
|
| a | 23 + 2 | 30 + 5 | 18 + 2 | 50 + 5 |
| b | 23 + 2 | 30 + 5 | 13 + 2 | 65 + 5 |
| c | 23 + 2 | 30 + 5 | 3 + 2 | 85 + 5 |
| d | 23 + 2 | 30 + 5 | -15 + 2 | No requirements |
| e | min. 20 | No requirements | Reference temperature
Θ3 = Θ1 + (55 + 5) |
No requirements |
The following permissible deformations apply:
| Test parameter | class 1 (x), (mm) | class 2 (x), (mm) | class 3 (x), (mm) |
| torsion, T | 8,0 | 4,0 | 2,0 |
| Longitudinal curvature, B | 8,0 | 4,0 | 2,0 |
| Transverse curvature, C | 4,0 | 2,0 | 1,0 |
Relevant standards:
Test standard(s):
DIN EN 1121 – Behaviour between two
different climates – Test method
Classification standard:
DIN EN 12219 – Doors – Climatic influences – Requirements for classification
Requirements and classification
Minimum requirements in Germany:
| Requirement according to: | class / limit value |
| E DIN 18105 | class 2 (c) for entrance doors to flats |
Relevant standards:
Test standard(s):
DIN EN 1121 – Behaviour between two
different climates – Test method
Classification standard:
DIN EN 12219 – Doors – Climatic influences – Requirements for classification
Requirements and classification
Minimum requirements in Germany:
| Requirement according to: | class / limit value |
| E DIN 18105 | class 2 (c) for entrance doors to flats |
Differential climate behaviour for windows
The necessity of the verification of the differential climate behaviour according to DIN EN 13420 is to be specified by the planner. The verification in the differential climate on windows is only necessary on diffusion-impaired constructions or constructions at risk of deformation.
In addition, the test certificate may be required for rooms with high moisture loads such as swimming pools and wet room cells.
Differential climate behaviour for external doors
In the case of external doors, this verification is generally required in order to state sufficient serviceability. Since the differential climate has a direct connection to the deformation behaviour of the door leaf(s), the maximum permissible deformations in the corresponding class are to be specified by the planner according to Table 25. Contrary to the specifications in the product standard DIN EN 14351-1, the door leaf height may only be increased by 12.5 cm more or higher than tested, as the deformation in relation to the door leaf height does not increase linearly but exponentially.
| Test parameter | class 1 (x), (mm) | class 2 (x), (mm)
min. requirement* |
class 3 (x), (mm)
special requirement |
| torsion, T | 8,0 | 4,0 | 2,0 |
| Longitudinal curvature, B | 8,0 | 4,0 | 2,0 |
| Transverse curvature, C | 4,0 | 2,0 | 1,0 |
| Local flatness | 0,4 | 0,3 | 0,2 |
| X test climate defined in DIN EN 1121 and/or in DIN EN 1294
T final torsion B absolute difference between final and initial torsion or longitudinal curvature or the actual absolute final torsion or longitudinal curvature, whichever is greater C final transverse curvature * Class 3, i.e. max. 2.0 mm longitudinal curvature is recommended for arcade doors. |
|||
Maxium permissible deformation for doors (according to table 10 of DIN 18055)
For exterior doors made of non-hygroscopic materials, verification in test climate c is not necessary, all other exterior doors are to be tested in the order of test climates c, d and e. The permissible deformations according to Table 25 are to be specified in the planning depending on the test climate according to Table 26 [Classification example: Class 2 (c, d, e)= door leaf made of wood and wood-based materials exposed to test climate c, d, and e; max. deformation 4.0 mm].
For exterior doors, only the deformations of classes 2 and 3 according to DIN EN 12219 are permissible for the door leaves / door wings (see Table 25). These deformation values also apply to exterior doors in use, whereby the framing can have a deformation value of max. 1.0 mm.
Class 3 according to Table 26 is recommended for external doors with special operating forces = Class 3 and 4 according to Table 27, as otherwise proper function cannot be guaranteed.
For tests in test climate e, the evaluation of the deformation takes place at the end of the test duration of 24 h. Experience shows, however, that the maximum deformation is reached within the first 3 hours and decreases again with longer irradiation periods. Therefore, it is recommended to consider not only the deformation value after 24 h but also the maximum deformation value within the entire test period.
Explanation: Experience has shown that exterior doors with high thermal insulation = low Uf value that were only exposed to the sun for a short time could no longer be opened. After longer exposure to sunlight, opening was then possible again. This is particularly problematic with dark coatings and materials with high thermal expansion (a-value). In case of a complaint, the max. deformation is decisive for the operability.
Contact
Andreas Nerz
(0)8036 674947 – 0