New accessibility standard reduces maximum threshold height on doors
Following the entry into force of the European Directive DIN EN 17210 “Accessibility and usability of the built environment – Functional requirements”, a revision of the national series of standards DIN 18040 was also required. One notable amendment is the new maximum permissible threshold height on doors and window(s): Instead of two centimetres as before, it should not exceed one centimetre since 2024. This is a major challenge for responsible planners and architects.
Accessibility of buildings is one of the most important development topics in the construction industry and is often a focus of current adjustments to standards and regulations. The good news is that the key requirements for doors and windows and their installation position have not fundamentally changed with the new DIN EN 17210 and are essentially retained. But it is the new "1 cm threshold height measure" that is reigniting the open discourse among experts in this area. Building barrier-free doors and ceiling-height window doors has always been a complex task due to the many trades involved. There is concern that this task is now set to become even more complex due to the new requirement.
E DIN 18040-1:2023 uses the following new wording regarding the threshold of doors:
"Where possible, door openings should always be designed with level transitions. If door stops and raised thresholds cannot be avoided, the threshold height must not exceed 1 cm. Door stops and raised thresholds must be designed so that they can be easily rolled over and rule out the risk of tripping. The risk of tripping is avoided if door stops and raised thresholds are bevelled or rounded, for example."
Practical help from ift Rosenheim
The main complaints from critics regarding the revised wording focus on the lack of a precise description of the reduced mass of the threshold height from 2 cm to 1 cm, meaning that there is too much room for "millimetre discussions". The formulation of the protection objective "easy to roll over" is also too vague and difficult to validate. In order to counteract this discourse on threshold height and to be able to offer an objective comparison, ift Rosenheim has published the ift guideline "BA-01/1 Determination and classification of roll-over suitability of thresholds", which makes it possible to determine and classify the roll-over suitability of different provider systems. Discussions or disputes can also be avoided if the contractor communicates the technically feasible threshold level before execution and has it approved by the client.
Threshold formation for window doors is treated in the same way as for doors
In future, the new exemption with a maximum threshold height of up to 1 cm will also apply to floor-to-ceiling window doors, i.e. balcony and patio doors. This is because DIN EN 17210 does not recognise the term "window door". Instead of the window category, it assigns these special doors to the "free seating" category (terrace, loggia or balcony) in the new formulation, with reference to the same level transition as for apartment entrance doors and doors.
Due to the amended reference, the same requirements as for doors will apply to window doors in future. A technical necessity, on the other hand, is no longer required and does not need to be proven. Overall, however, this innovation means that stop seal systems for window doors can be implemented in a more technically demanding manner.
The solution: Planet X3 drop-down seal with modular click threshold system
ASSA ABLOY offers an innovative solution for full accessibility in the area of door systems, which also meets the newly defined maximum threshold height of 1 cm in any available product version. In combination with the modular and versatile click threshold system, the Planet X3 drop-down seal is suitable for both new builds and renovations.
The modern door seal ensures complete sealing of external doors by simultaneously moving downwards, left and right. This means that heavy rain and other extreme weather conditions are also no problem.
In order to meet the various requirements and construction situations, the drop-down seal is available in combination with a modular system of three modular click threshold systems. These click thresholds help prevent thermal bridges indoors through thermal separation and are therefore energy efficient and cost-effective.
All variants of the click thresholds impress with a functional and discreet design with concealed screws. The installation of the Planet X3 with click threshold system is also easy, fast and convenient.