The model code is not law
The conference of state building ministers prepares a Musterbauordnung, model building code, most recently in its 2002 version with later amendments. It serves to align the state codes.
It has no legal force of its own. No project is consented under it. What governs is always the code of the state in which building takes place, together with its ordinances for special buildings. It serves only to align the state provisions.
The states have adopted the model code to differing degrees. On building classes they largely coincide, on separation distances considerably less, and on procedures not consistently at all.
A rule follows that shapes this whole branch: the model code serves understanding of the system; the state code serves application. The article on comparing the state codes covers the differences.
The four questions for every project
Every project passes through the same four assessments under building regulations law, whatever the state. The answers, by contrast, differ by state.
| Question | Subject |
|---|---|
| Which building class | classification by height, units and position |
| Special building or not | classification by use and size |
| Which procedure | exemption, simplified or full procedure |
| Which separation distances | depth of the areas to be kept clear |
The first two are answered independently of one another. A building may fall into the lowest class and be a special building at the same time.
The building class drives the requirements
The model code divides buildings into five classes, essentially by height, number and size of units, and whether the building is detached. The classification governs requirements and procedure at once.
Two definitions are decisive here and are regularly misapplied. Both concern classification into a building class.
| Definition | What actually applies |
|---|---|
| Height is not ridge height | what governs is the finished floor level of the highest storey containing habitable rooms |
| Detached means without physical connection | not a particular minimum distance; what matters is that no connection exists |
The classification affects almost every substantive requirement, from fire safety through structure to escape routes. The article on building classes covers the detail.
The special building drives the procedure
Sonderbauten, special buildings, are installations of particular type or use, listed in a catalogue in the model code: high-rise buildings, assembly venues, retail premises, hospitals, schools and others. The catalogue is exhaustive.
Their most important effect is procedural. Special buildings fall in principle neither under exemption nor under the simplified procedure but under the full consent procedure. All requirements of building regulations law are therefore examined.
For the designer that means considerably different effort, with a wider scope of examination, more extensive evidence, and longer procedures. It must be reflected separately in the fee calculation.
The procedures differ in scope of examination
| Procedure | Scope | Typical application |
|---|---|---|
| Exemption from consent | no examination, notification only | simple projects within a local plan |
| Simplified consent procedure | restricted | buildings in the lower classes |
| Full consent procedure | complete | special buildings and higher classes |
A reduced scope of examination does not mean reduced requirements. What the authority does not examine must nonetheless be complied with, and responsibility for that sits with the parties involved.
This is the commonest misconception in building regulations law and it carries economic consequences: a project consented under the simplified procedure has not been examined on every point and may nonetheless be defective. The article on consent procedures compared covers the differences.
Separation distances vary most
Of all areas of building regulations law, separation distances show the greatest variation between states. The range spans more than a factor of five.
The underlying principle is the same everywhere: areas must be kept clear in front of external walls, their depth derived from wall height. The factor, the minimum depth, the treatment of roof surfaces and the exceptions for subordinate elements differ considerably.
A statement about separation distances without naming the state is worthless. The article on separation distances covers the system and the differences.
Who bears responsibility
Building regulations law names those involved and allocates responsibility to them, namely the client, the designer, the contractor and the site manager. That allocation is independent of the contractual division of roles.
Associated with this is Bauvorlageberechtigung, the entitlement to prepare and submit building applications. It is tied to professional law requirements and is regulated by the states.
For design practices this is a question of access to be settled before any commission. The article on entitlement to submit covers the conditions.
The relationship to planning law
The two fields are frequently conflated although they answer different questions. The division runs between location and building.
| Field | Level | Question |
|---|---|---|
| Planning law | federal | whether and for what use building may take place at a location |
| Building regulations law | state | how the individual building must be constituted |
A project must pass both. A project permissible in planning terms may fail on separation distances; a building faultless under building regulations may fail on its type of use. The branch on planning law covers the other side.
What follows for cost work
Three relationships matter for early cost planning. All three follow from the classification of the building.
| Relationship | Cost effect |
|---|---|
| The building class determines the requirements and therefore the cost | moving from one class to the next changes requirements, procedure and certifications at once |
| A special building generates its own design effort | concepts, evidence and consultations arise in addition |
| The procedure determines duration | the time between application and consent affects holding costs |
Related articles
This article reflects the position of the rules at the date of checking and serves professional orientation. It does not constitute legal advice and does not replace assessment of the individual case.