Outside is a term in German building planning law in connection with the admissibility of building projects. In the outdoor area according to Building Code (BauGB), all plots of land that are neither within the scope of a qualified development plan nor belong to a district with built-up areas are included. 
The qualified development plan is defined in accordance with simple development plan (Section 30 (3) BauGB), on the other hand, can belong to the outside area.  Areas in a district with built-up areas do not belong to the outside area, but to the inside area according to BauGB.Paragraph 1 and 2 BauGB. Areas in the area of a
Larger open spaces surrounded by buildings can also be part of the outside area if they clearly interrupt the building context so that they do not appear to be vacant lots.   For the assessment of the legal planning admissibility of a project, it always depends on its specific spatial location and thus on the assignment to one of the area categories.
Admissibility of construction projects under construction planning law
The admissibility of building projects outdoors is based on Building Code (BauGB). There are basically two types of external area projects : privileged and other projects .  Privileged projects are generally permitted in the outdoor area, provided that they are not opposed to public interests and adequate development is ensured. The legislature has, as it were, systematically assigned them to the outside area. On the other hand, it is the aim of the law to keep the outside area free of non-privileged buildings and thus to avoid urban sprawl. Other projects are therefore already inadmissible if there are public concernsbe affected. The difference between privileged and other projects lies in the fundamental difference in their relationship to public concerns. Since the outside area makes up by far the largest part of the federal territory, the related regulation is of outstanding importance.
The privileged projects are finally listed in Section 35 (1) BauGB; an analogy or extension of the catalog is not permitted.  According to the will of the legislature, the corresponding facilities belong in the outdoor area because of their intended purpose or because of their effects on the environment. These include projects that
- serve an agricultural or forestry business and only occupy a subordinate part of the operating area,
- serve a horticultural production company,
- serve the public supply of electricity, gas, telecommunications services, heat and water, sewage management or a local commercial operation,
- due to their special requirements on the environment, because of their adverse effect on the environment or because of their special purpose, should only be carried out outdoors, unless it is the construction, modification or expansion of a structural system for animal husbandry that is part of the scope is not subject to number 1 and which is subject to an obligation to carry out a site-related or general preliminary assessment or an environmental impact assessment in accordance with the law on environmental impact assessment, whereby in the case of cumulative projects for the assumption of a certain relationship, those animal husbandry facilities must be taken into account that are on the same company or building site lie and are connected to common operational or structural facilities,
- serve to research, develop or use wind or water energy,
- serve the energetic use of biomass in the context of an agricultural or forestry operation or an intensive animal husbandry,
- serve to research, develop or use nuclear energy for peaceful purposes or to dispose of radioactive waste,
- serve the use of solar radiation energy in, on and on the roof and exterior wall surfaces of permitted buildings.
Privileged projects must not “stand in the way” of public interests and only adequate development must be ensured. The building permit authority has no discretion when deciding on a building application : If the requirements are met, a claim exists and a project must be approved.  After permanent abandonment of the permitted use, privileged projects must be dismantled and the soil seals removed (Section 35 (5) sentence 2 BauGB); Only agricultural, forestry and nuclear power plants are exempt from the dismantling obligation. The building permit authority should ensure that these obligations are met by building loads or in some other way (Section 35 (5) sentence 3 BauGB).
If a project in the outdoor area cannot be assigned to one of the listed privileged projects, it is a different project according to Section 35 (2) BauGB. Other projects are only permitted if public interests are “not impaired” and development is secured. However, this means a concrete impairment, the mere abstract possibility of an impairment is not sufficient.   The phrase "may in individual cases" means no granting of discretion  ; if the requirements of Section 35 (2) BauGB are met, the project is permissible under planning law. 
A subgroup of the other projects  are the beneficiary projects (or partially privileged projects  ), which are finally listed in Section 35 (4) of the BauGB (supplemented by December 31, 2019 in accordance with (9) of the BauGB). These are projects that are an existing and protectedHave building as a starting point. These include, for example, changes in use, expansions or replacement structures for previously permitted buildings. Certain public interests may not be opposed to the beneficiary projects listed in the Building Code. In this respect, irrelevant public concerns would be "that they contradict representations of the land use plan or a landscape plan, impair the natural character of the landscape or cause fear of the emergence, consolidation or expansion of a fragmented settlement".
The issues that may conflict with a project in the outdoor area are listed as examples in Section 35 (3) BauGB   . In this respect, the list is not exhaustive; other issues relevant to land law and other legal provisions (see Section 29 (2) BauGB) may also be relevant.  The issues listed include settlement structural issues (avoidance of urban sprawl), issues of nature conservation and landscape management, soil protection, flood protection or the representations of the land use plan. In addition, any other project in the outdoor area may also be inadmissible if, due to the scope, there is a planning requirement, i.e. a development plan must be drawn up. A zoning plan or spatial planning plan can also be used to concentrate privileged projects on specific locations (so-called plan reservation  according to Section 35 (3) sentence 3). This can be relevant for wind turbines , for example . 
The public concern of urban sprawl
Housing projects in particular often fail in the outdoor area due to the public concern of urban sprawl (Section 35 Paragraph 3, Sentence 1 No. 7 BauGB), for example on the outskirts of villages. The border between inside and outside runs behind the last house; the adjoining areas are already outside. With the construction of more houses, the development is pushed into the outside area, so to speak. If the resulting structural development cannot be limited, this represents an undesirable urban sprawl.
Apart from the coherent built-up areas, each individual building basically represents a split settlement. If there are several buildings, one speaks of a split settlement. The creation of new splinter settlements as well as the expansion or consolidation of existing settlement splinters is generally not permitted. The case law has developed exceptions for the expansion and consolidation of existing splinter settlements. Thereafter, expansion or consolidation without urban sprawl is an exception if it is subordinate.
Example : Consider a split settlement consisting of six houses and between which there is a gap in which another house would fit. This consolidation of the settlement around another house is conceivable because one house is still subordinate to six existing houses. When the settlement development of this splinter is completed, there is no role model effect.
In certain cases, the municipality can facilitate projects in the outdoor area through an outdoor area statute (Section 35 (6) BauGB). For built-up areas in the outer area that are not predominantly agricultural and in which there is residential development of some weight, the municipality can determine further relief for other projects by statute. Under “built-up areas in the outer area” are to be seen settlements, such as splinter and scattered settlements, which are not districts within the meaning of Section 34 (1) BauGB, but this term is not limited to such settlements. 
Agreement of the community
According to consent of the municipality is required for all building projects outdoors . The deadline for the decision on the communal agreement is two months; after this period the agreement is deemed to have been granted. The consent of the municipality may only be refused for reasons resulting from Section 35 of the BauGB (additional: urban development) (Section 36 (2) sentence 1 of the BauGB). It does not matter whether the project corresponds to the planning ideas of the municipality  or whether the municipality would like to develop other planning options. However, the granting of consent does not prevent the municipality from drawing up a development plan contrary to the project or from changing an existing development plan and revising itTo secure plan-securing instruments (change lock or postponement).  A change block, which is intended to allow the municipality to set up a specific planning concept, would be ineffective due to the lack of security. Building Code, the
The authority that has to decide on the building application or other permit is only bound by the decision of the municipality if it is lawful. If the consent is given even though the prerequisites for it are not met, the authority that has to decide on the application can still reject it.
In return, the licensing authority can also replace the consent of the municipality if the refusal by the municipality is legally incorrect (Section 36 (2) sentence 3 BauGB).
See also in Switzerland
In Switzerland, the Hofstatt Law grants the rebuilding of a destroyed or demolished building to the previous extent, especially in areas that have not been over-planned.
- Ronald Kunze, Hartmut Welters (ed.): The practical handbook of building land use planning. Loose-leaf collection with ongoing updates . WEKA Media, Kissing 2000–2011.
- Ronald Kunze, Hartmut Welters (Hrsg.): BauGB Innovations 2007. Legal text and innovations at a glance, WEKA-Media, Kissing 2007, ISBN 978-3-8277-1208-0 (commentary on the innovations and legal text BauGB 2007 including BauNVO).
- Ronald Kunze: Keyword “outside area” in “Building Regulations in Pictures” . WEKA-Media, Kissing 2007.
- the Building Code
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 35 paragraph (marginal number) 2.
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 35 Rn. 3.
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 34 Rn. 9.
- BVerwG , decision of September 15, 2005, file number 4 BN 37.05 , Rn. 3, ZfBR 2006, 54, beck-online.
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 35 Rn. 1.
- William Söfker in Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, work status: 136. EL October 2019, § 35 para. 21.
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 35 Rn. 5.
- William Söfker in Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, work status: 136. EL October 2019, § 35 para. 166
- William Söfker in Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, work status: 136. EL October 2019, § 35 para. 76.
- BVerwG, judgment of May 26, 1967, file number IV C 25.66
- BVerwG, judgment of April 29, 1964, file number IC 30.62 .
- Stüer / Stüer, Building in the outdoor area, I. Building in the outdoor area (§ 35 I BauGB): Introduction Rn. 15th
- William Söfker in Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, work status: 136. EL October 2019, § 35 para. 73.
- Stüer / Stüer, Building in the outdoor area, I. Building in the outdoor area (§ 35 I BauGB): Introduction Rn. 2.
- Wilhelm Söfker in: Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, status: 136th EL October 2019, Section 35 marginal no. 75.
- William Söfker in: BeckOK Building Code, 49th Ed. 1.2.2020, BauGB § 35 Before Rn. 1.
- BVerwG, judgment of May 20, 2010, file number 4 C 7.09 , NVwZ 2010, 1561, beck-online.
- BVerwG, judgment of May 18, 2001, file number 4 C 13.00 , NVwZ 2001, 1282 (1283), beck-online.
- William Söfker in Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, work status: 136. EL October 2019, § 35 para. 108.
- William Söfker in Ernst / Zinkahn / Bielenberg / Krautzberger, Building Code, work status: 136. EL October 2019, § 35 para. 169.
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 36 Rn. 13th
- Olaf Reidt in: Battis / Krautzberger / Löhr, Building Code, 14th edition 2019, § 36 Rn. 6th
- BVerwG , judgment of February 19, 2004, file number 4 CN 16.03 , NVwZ 2004, 858, beck-online.