Background knowledge: What about building permits for solar systems, solar carports and solar modules?

According to public building law in Germany, due to the constitutional protection of the freedom to build, the decision to grant approval is not at the discretion of the building authority: If a project is compatible with the regulations of public law, the citizen is entitled to the granting of a building permit.

The basis for the building permit is the building regulations or state building regulations of the respective federal state, because the authority for building regulations lies with the respective federal states.

The requirements of the building regulations mainly relate to the development, including parking spaces for motor vehicles. The aim of the building regulations is to avert dangers to life and limb, to avoid damage to other people's property and to ensure public safety and order.

Conference of Construction Ministers

To ensure that the differences in building law in the respective countries are not too great, there is an annual conference of building ministers. A working group of ministers and senators from the 16 states of the Federal Republic of Germany responsible for urban development, construction and housing. The Federal Minister responsible for construction also regularly takes part in this conference of construction ministers.

Model regulations and model decrees adopted by the Conference of Construction Ministers serve as the basis for implementation into specific state law. So they have no direct legal effect. Each country decides to what extent the state regulation follows the model. The compilation is supplemented by instructions and work aids.

Suitable for:

• Model building regulations MBO

German Institute for Structural Engineering (DIBt)

However, there is an agreement between the federal and state governments for the approval of non-regulated construction products and types. A technical authority in the construction sector, the German Institute for Construction Technology (DIBt), is responsible for this. It issues approvals, general building approvals, type approval and reports for construction products and types.

The background:
After the Second World War, building supervision and building regulations in the Federal Republic of Germany fell under the responsibility of the federal states. When it came to the approval of construction products, they were confronted with two problems: On the one hand, the technical complexity of the approval procedures increased significantly with the numerous new products and processes of the time of the economic miracle. On the other hand, the building materials industry demanded approvals with nationwide validity. In response to this, the Institute for Structural Engineering was founded in 1968 on the basis of a federal-state agreement. The institute took over the licensing system and other structural engineering tasks (nationally).

In the “ Model Administrative Regulations for Technical Building Regulations (MVV TB) ”, the DIBt brings together the technical rules for the planning, dimensioning and execution of buildings and construction products in one regulation.

These include mechanical strength, stability, safety and accessibility during use.

Construction products or types of construction for which there are no technical regulations are referred to as “non-regulated construction products” or “non-regulated types”. In Germany, general building approval can only be granted by the German Institute for Building Technology (DIBt) upon application. As a rule, the validity of a general building approval is limited to five years. After the validity expires, a corresponding application for an extension can be made.

If you want to use your construction product throughout Germany with a general building authority approval, your path automatically leads to the DIBt, the German approval body for non-regulated construction products. Our experts will accompany you step by step through the process – from application to approval.

➡️ Application for admission (abZ) to the DIBt

Suitable for:

• What you need to consider with transparent glass modules for solar

In Germany, general building approval can only be granted by the German Institute for Building Technology (DIBt) upon application. As a rule, the validity of a general building approval is limited to five years. After the validity expires, a corresponding application for an extension can be made.

Before an abZ is issued for a construction product or type, all important aspects are checked, in particular safety-related properties and influences. These include stability, protection against harmful influences, health protection and protection of the natural resources as well as fire, heat, noise and vibration protection and traffic safety. The legal basis for general building approval is the model building regulations.

A typical product that is not uniformly standardized in Germany, but is applicable through general building authority approvals, is prestressing steel and corresponding accessories for prestressed concrete construction.

Thermal insulation composite systems and large-format facade panels for rear-ventilated facades are also among the building products that can be used with general building authority approval.

The approval process for issuing a nationally valid, general building authority approval begins with the submission of a corresponding application to the DIBt. The applicant is usually the manufacturer of a product. If necessary, following a recommendation from an expert committee, the DIBt determines the tests to be carried out and the evidence to be provided. After the applicant submits the evidence, the DIBt discusses the case and grants approval, again if necessary with the help of the expert committee.

The abZ is a temporary approval!

The costs for issuing a new abZ are set out in the DIBt statutes. Depending on the product or design and the effort involved, the fees for a five-year approval range between 500 and 30,000 euros . If a shorter period of approval is requested in the application, the costs are reduced by 10% per year of shortening. The fees for extending an existing license range between 10% and 50% of the cost of a new five-year license.

If an assessment document (EAD) exists at European level, a European Technical Assessment (ETA) can be applied for. The ETA regulates the placing on the market of the construction product/type in Europe. Further requirements (e.g. abZ) may exist at national level for usability in the respective member state.

☑️ According to the model building regulations “MBO” of the Conference of Building Ministers, roof solar systems do not require a building permit.

⚠️Carport or solar carport

A carport or solar carport is a structural system and therefore generally requires approval under public building law. In Baden-Württemberg, carports can be set up indoors with a gross volume of up to 40 cubic meters and outdoors with a gross volume of up to 20 cubic meters without a permit. In general, you should always check with the responsible building authority beforehand. Regulations and conditions of the respective federal state can change at any time. It is best to search for it on the Internet using “Application for a building permit using the simplified procedure” for the respective federal state.

⚠️ Solar parks or open space systems

Large photovoltaic systems such as outdoor systems always require approval.

⚠️ Use of solar modules

According to the DIBt model administrative regulations for technical building regulations

Model Administrative Regulations Technical Building Regulations of DIBt

Example of glass-glass solar modules (applies to B 3.2.1.25)

⚠️ Individual module area larger than 2.0 m²

⚠️ Tilt angle greater than 75° (e.g. as a solar facade)

⚠️ Solar carports without a roof (e.g. without trapezoidal sheet metal covering, modules are accessible from below)

➡️ Require general building authority approval (abZ), application for approval to DIBt

➡️ This particularly applies to overhead glazing on patio roofs or carports or solar carports

The model administrative regulation Technical Building Regulations (MVV TB) stipulates that certain rules of “DIN 18008 Glass in Construction – Dimensioning and Construction Rules” must be applied to glass constructions. For laminated safety glass (VSG), the pendulum impact test is proof according to “DIN EN 12600 Glass in construction: Pendulum impact test – method for impact testing and classification of flat glass”.

See also:

➡️ VSG float glass: laminated safety glass – float glass

➡️ VSG TVG glass : laminated safety glass – part toughened glass

Float glass is a flat glass of simple glass. It is manufactured using the “float glass process”. The disadvantage of float glass is that it breaks into many sharp-edged and pointed pieces. The risk of injury is high.