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Data exchange

In the data exchange, already collected data of a building project, e.g. of a bill of quantities, is made available for other parties involved for electronic processing.
If these partners want to exchange data, they need to agree on a common basis. The conventions necessary for this are described in the regulations for the GAEB data exchange GAEB DA XML. They are recognized as a national standard.
This data exchange supports all parties involved in the building process in the exchange of information concerning the execution of construction measures.

The bases is developed within GAEB in the lead working group 13 „Programming Systems“ “, coordinated with all participants and update in line with demand.
Participants are:

  • Building authorities of the Federal Republic, the federal states and the municipality
  • Architects and engineers
  • Larger user groups such as the DB Netz AG,
  • The executing building industry
  • Universities
  • DIN Deutsches Institut für Normung
  • Building software companies

GAEB defines the interface and processes it professionally and dv-technically. It is made available for the building software companies. These integrate the regulations of the interface DA into their expert applications. The producers of the expert applications are responsible for the correct implementation of the interface description.

GAEB-data-files are structured and standardized formats that are developed according to GAEB regulations and exchanged independently from hard- and software via the GAEB interface.

The GAEB interface – GAEB DA XML – is a structured and standardized interface, developed according to GAEB regulations. It enables the parties involved in the building process to exchange GAEB-files that contain building information, for example bill of quantities.
These information can be exchanged electronically between the parties involved in the building process. The regulations of GAEB are correctly realized in the interface which enables every EDV-system to properly assume and process the data.

First and foremost through the file endings. These are technically prescribed, namely:

File ending e.g. GAEB-Versions Example
.D83 GAEB 1990 Datei.D83
.P83 GAEB DA 2000 Datei.P83
.X83 GAEB DA 2000 XML

The phases of the data exchange set the content of a file in GAEB format.
The naming of the exchange phases DA 81 to DA 86 is the same in all DA-versions.

GAEB-files can be opened and processed with a suitable AVA- or calculation-software respectively, that has a corresponding GAEB interface. If the software is not available, at least a viewing tool (viewer) is needed that can also be downloaded for free in the internet. If GAEB-files are to be processed, the viewer needs to be equipped with a fill in function.
STLB-Bau additionally provides a STLB-Bau bidding form which can be used to read and also process GAEB-files.

GAEB-converter, GAEB-viewer and similar products that are available on the market, are part of those tools that have been developed from third parties in the background of GAEB in their own responsibility as support of GAEB work. If applicable, the signs for textual supplements are:
(TA = text supplement client and/or TB = text supplement contractor)

GAEB DA XML is not standardized but is valid as a national standard which is documented in PAS 1067.

Norms are an ordering instrument of our technical world. The norming-work of DIN is a technical and research related service. DIN-norms are based on consensus.
On the other hand, there are technical regulations and agreements that have been reached between a group of companies or associations. For a lot of regulations, further consensus with all interested parties is not necessary.
Here, DIN provides a new and effective way. This is the development and publication of publicly available specifications PAS (PAS = Publicly Available Specification).
PAS can be developed speedily. And just as speedily, Beuth Verlag, who cooperates with DIN, organizes the publication of PAS.
DIN experts check the relation of PAS with the German, European and international norms. The result is summarized on the first page of PAS.
The author of this document who is also mentioned on the first page of PAS is solely responsible for its content.
DIN provides PAS in Germany and worldwide via the distribution network of the Beuth Verlag. Just as bibliographic data of a DIN-norm, they are included in catalogues, electronic media and the internet. Foreign norm institutes receive a copy of PAS.

The CD concerning the data exchange, that can be obtained via Beuth Verlag, contains information for the programming of the interface and for the development of bill of quantities.

The GAEB data exchange with GAEB DA XML contains, as opposed to the previous regulations concerning data exchange of 1990, a fundamentally changed syntax.
DA 1990’s method is line oriented. That means, every line has its own notation (e.g. ZA26-Langtext-) with corresponding content.
GAEB DA XML is element oriented. This means every information has its own key word. Thus, the way to modern data communication is cleared.
Currently, the exchange of LV-data is enhanced with the phase “calculation”. Also, requirements for the exchange of data for catalogues, costs, building parts, scheduling, inquiry/order have been set up with the introduction of GAEB DA XML.

Different software companies offer modules for conversion. However, this only applies to contents that are present in DA 1990 as well as in GAEB DA XML.

XML – short for eXtensible Markup Language.
XML is an internationally acknowledged description language; at the same time it is a meta-language, a language for the definition of the structure of a document. XML allows for the coding of documents and the inclusion of qualified electronic signatures. Thus the electronic exchange of the building contract is possible.

Here, “DA” generally stands for “Datenaustausch” (data exchange. The single exchange phases are marked with “xnn”. “. The exchange files get the corresponding endings “.xnn” “nn” stands for the respective exchange phase: e.g. “.x83 tendering order”.
x81, Bill of quantities transfer – is the notation of an exchange file that hands over the BoQ-data of the architect/engineer to the owner (OWN) in the area of planning in a particular format
x83, Bidding order – is the notation of an exchange file that hands over the BoQ-data of the OWN to the contractor in a particular format.
x84, Bidding offer – is the notation of exchange file that contains the offering data in a particular format and is given back to the OWN.

Sample files for GAEB DA XML, Version 3.0, are available to download on files for Version 3.1 are in preparation. In the case of texts that exceed the usual standard, GAEB recommends to formulate freely and mind the syntax of STLB-Bau.

GAEB provides downloads of sample files on its homepage. These can be used to test an AVA-program for its adherence to the regulations of the data exchange.
The correct implementation of the GAEB interface in a software is also guaranteed by certification of BVBS. You can find a list of certified software products on