Moisture-variable diffusion inhibiting layers
Moisture-variable diffusion-inhibiting layers are films regulating moisture. They are used, for example, in flat-sloping or pitched, fully insulated, non-ventilated roof constructions with metal roofing or waterproofing on formwork or planking and ensure that moisture that has penetrated can be released again.
Regulatory framework
For construction products used as moisture-variable diffusion inhibiting layers, DIBt grants national technical approvals (abZ) because
- neither Technical Building Rules (cf. MVV TB Chapter C 2) nor generally recognised technical rules exist.
European Technical Assessments (ETAs) can also be issued for these construction products.
For construction techniques comprising construction products used as moisture-variable diffusion inhibiting layers, DIBt grants general construction technique permits (aBG) when there is no conclusive technical rule for design and execution.
Moisture-variable diffusion-inhibiting layers are provided for in DIN 68800-2:2022-02, Section 7.5 for certain constructions to protect the timber and ensure long-term stability. The layers must regulate moisture on a permanent basis. Technically speaking, this special property is achieved by means of a moisture-variable diffusion resistance.
National procedure
To prepare an abZ/aBG for your construction product, we need an application from you. We recommend that you contact us prior to doing so. Feel free to send us your enquiry informally via email to dibt(at)dibt(.)de or to the competent technical contact listed in the top right.
For a first assessment, please send us the following information:
- Description of the construction product and its intended field of use
- e.g. material, configuration, number of sizes, variants, dimensions
- e.g. use in walls, ceilings, interior construction, building services
- Description of the construction technique and its field of application
- e.g. design of walls, ceilings, elements, etc., and interaction of components
- e.g. application in foundation engineering, reinforced concrete construction, building insulation; as load-bearing or non-load-bearing component; under static and quasi-static loading; fire exposure; other environmental exposures
- Information regarding impact on regulatory concerns
- in particular structural integrity, fire protection, health and environment protection, sound insulation as well as thermal performance
- Explanation of need for an abZ/aBG
- Do you significantly deviate from the Technical Building Rules?
- Or do neither Technical Building Rules nor generally recognised technical rules exist?
- Contact details
- preferably email address and/or telephone number, as well as name, organisation/company, and postal address
We will then contact you to clarify the next steps.
If you already hold a DIBt approval and/or construction technique permit and wish to apply for an amendment, supplement, or renewal, please use the form provided below.
- pdf-Datei Application for amendment / supplementation / renewal of a national technical approval and/or construction technique permit (4 pages ) Last updated: 10 April 2024; Application form
European Technical Assessment (ETA)
To start the ETA procedure, please submit the form below. We will then check if the prerequisites for issuing an ETA are met, i.e., in particular, if the product is not fully covered by an existing harmonised standard. If the prerequisites are met, we will check whether a European Assessment Document (EAD) covering the requested assessment scope already exists or still needs to be developed. If an EAD needs to be developed or amended, a complete technical file needs to be established before the procedure can begin.
- pdf-Datei Form for requesting a European Technical Assessment (ETA) (2 pages ) Last updated: 11 March 2025
| Subject concerned | Applicant | Decision no. |
Validity
from / to |
|---|---|---|---|
| Feuchtevariable Dampfbremsbahn "Vario® KM Duplex UV" | SAINT-GOBAIN ISOVER G+H AG Bürgermeister-Grünzweig-Straße 1 67059 Ludwigshafen | Z-9.1-871 |
Z:
26.04.2023 G: 17.02.2028 |
| Feuchtevariable Dampfbremsbahn "Vario® XtraSafe" | SAINT-GOBAIN ISOVER G+H AG Bürgermeister-Grünzweig-Straße 1 67059 Ludwigshafen | Z-9.1-872 |
Z:
26.04.2023 G: 17.02.2028 |
| Feuchtevariable Dampfbremse "URSA SECO SDV" | URSA Deutschland GmbH Carl-Friedrich-Benz-Straße 46-48 04509 Delitzsch | Z-9.1-883 |
Z:
19.10.2023 G: 19.10.2028 |
| Feuchtevariable Dampfbremsbahn "Superbran Trio" | SUPERGLASS DÄMMSTOFFE Industriestraße 12 64297 Darmstadt | Z-9.1-884 |
Z:
13.09.2023 G: 13.09.2028 |
| Subject concerned | Applicant | Decision no. | Issued on |
|---|---|---|---|
| Humidity-dependent vapour control layers INTELLO and INTELLO PLUS | MOLL bauökologische Produkte GmbH pro clima Rheintalstraße 35-43 68723 Schwetzingen DEUTSCHLAND | ETA-18/1146 |
28.11.2019 |
| Humidity-dependent vapour control layer VC 102/090 05-5 | Lenzing Plastics GmbH & Co. KG Werkstraße 2 4860 Lenzing ÖSTERREICH | ETA-21/0916 |
21.02.2022 |
| ALUJET Climajet SD VARIO | ALUJET GmbH Ahornstraße 16 82291 Mammendorf DEUTSCHLAND | ETA-22/0286 |
13.06.2022 |
| URSA SECO SDV PLUS | URSA Deutschland GmbH Carl-Friedrich-Benz-Straße 46-48 04509 Delitzsch DEUTSCHLAND | ETA-23/0511 |
12.12.2023 |
| TargoVARIVAP N | Targo Specialty Products AG Brüelstraße 23 8932 METTMENSTETTEN SCHWEIZ | ETA-24/0122 |
17.05.2024 |
| Knauf Insulation LDS FlexPlus | Knauf Insulation GmbH Heraklithstraße 8 84359 Simbach am Inn | ETA-24/0256 |
27.05.2024 |