In the Federal Republic of Germany, the federal, the states and community administrators as well as a large number of non-public developers make use of the "Verdingungsordnung für Bauleistungen" (VOB) (Contract Procedures for Building Works) in the purchase of building works [VOB92].
The VOB provides rules for the procedure for the contract letting of public building contracts and formulates general contract conditions, which place the rights and duties of instructing parties and contractors in a balanced relationship. It has been incorporated into the standards of the German DIN - Deutsches Institut für Normung e.V - (German Standards Institute) and is thus neither law nor common usage rights [Schaa95].
The VOB [VOB92] is divided into three main parts:
Part A: General directions of contract letting for building works DIN 1960 .
Part B: General conditions of contract for the execution of building works DIN 1961.
Part C: General technical specifications for building works (ATV) DIN 18 299 to 18 451.
All government contract letting authorities of the state and the Länder, as well as towns, communities and municipalities are bound by the administrative regulations to basically apply the VOB, i.e. to use the procedures in Part A and to negotiate the contracts in accordance with Parts B and C. Furthermore, all other instructing parties of building works who utilise state means to finance their construction measures are obliged by their permission to also proceed in the same way [Schaa95].
Because of the alteration of the European Building Coordination Guidelines, it was necessary to translate these changes into national contract letting regulations. This was carried out by the insertion of "a" paragraphs in the VOB Part A [VOB92].
According to VOB / §2, general building works are to be "awarded to professional, capable and reliable applicants at reasonable prices. Competition should be the rule." The vehicle used for this purpose is that of a proposal request.
According to VOB, the contract letting is a designation for the whole procedure for the purpose of a construction contract starting with the request for a tender via the acceptance of the tenders up to the awarding of the contract ("Adjudication").
The proposal request process is divided into 3 steps:
Step I: Written request for the provision of a written tender before a certain date.
Step II: Formal tender opening, possibly in the presence of the tenderers (Submission).
Step III: Testing and evaluation of the tenders, followed by
- Award of the tender or
- Cancellation of the proposal request
Public proposal requests are publicised in daily newspapers, in official gazettes of the government, the Länder and those of other public-legal organisations or in professional journals.
In a limited proposal requests, the specifications documents are sent to a short list of applicants with letters. In approved special cases, deviations can be made from the public or limited proposal requests and a private contract can be made [Schaa95].
The two last named forms of proposal requests are favoured by the ATV-M 143 Part 5 [ATVM143-5a] for Relining processes and similarly also for other rehabilitation measures up to the availability of process-specific specifications with the following reasoning:
"The relining processes in sewage construction are special processes that can only be carried out by a limited number of tenderers in a suitable manner and in the desired quality. Thus, relining processes are building works in which a deviation from the usual public proposal requests can be allowed and a limited or private contract should be made.
Further grounds for this can be:
- The efforts expended for a public proposal requests are unreasonably high in comparison with the achievable advantages;
- The service is patent protected or requires special experience or capabilities;
- The services cannot be hived off from an awarded larger service without a disadvantage.
If the measure is not publicly requested, then 3 to 8 suitable applicants should be asked to tender possibly after carrying out a public tenderer competition. The competitors must provide evidence of their suitability and capabilities. An important component is the fulfilling of the requirement profile of the instructing party, which specifies what is expected of the competitors as regards building works, materials and quality assurance.
Subsidiary tenders that deviate in a technical sense from the service description should be permitted even without the return of a main tender."
In the non-public region, the ATV-V 143 Part 5 [ATVM143-5a] recommends carrying out the contract letting in the same way. For this there are basically two possibilities:
- "Leistungsbeschreibung mit Leistungsverzeichnis" Contract requirements with specification sheet
- "Leistungsbeschreibung mit Leistungsprogramm" Contract requirements with obligatory result contract.