If a deviation from the provisions of building planning law or building code law is desired, an application for an exception, exemption, or deviation may be filed. The building authority decides on the application, which must be supported by a statement of reasons.

In building permit proceedings, a decision on a requested deviation from the provisions of building regulations or an exception or exemption from planning regulations is made together with the building permit application.

A separate application for a deviation is only possible for structures under § 73 HBO. This is not possible for projects exempt from approval in planned areas (Section 63 HBO). In such cases, a decision on the deviation, exception, or exemption must be made in an approval procedure.