In 2013 there were some 995 hectares of vacant building land in Luxembourg which are classified as ‘Baulücken’. They are connected to infrastructure such as electricity and waste water. In principle, they are immediately available for construction and thus can tackle short- and intermediate-term needs for housing. To stimulate the use of these plots, the state has initiated the so-called ‘Baulückenprogramm’ (vacant lot identification and mobilisation programme). In Dudelange, the first project under the national programme is now underway.

Rationale for action

Tackling the housing shortage is a key priority on the political agenda in Luxembourg. By constructing more housing units, the shortage of living space can be reduced and prices could drop. Additionally, developing the vacant lots avoids urban sprawl. However, a limiting factor is their ownership structure as developing the lots for housing requires a consent of the owner. Only 6 % of these 995 hectares belong to public actors (state, municipalities and public funds). 94% belong to the private sector.

Owner structure of ‘Baulücken’ in Luxembourg: the majority is owned by private individuals (82.2%), followed by businesses (11.7%), municipalities (4.3%) and the state (0.7%). The structure shows the need to inform and cooperate with private owners in mobilising ‘Baulücken’ for urban development. Source: Ministry of Housing, 2016.


The national ‘Baulückenprogramm’ aims at activating these lots for the construction of housing. Developing these areas does not require long administrative procedures and it is possible to develop them relatively quickly. A first objective of the programme is to identify the lots and to make owners aware of how their lots could contribute in satisfying the demand for housing. In this process, municipalities act as intermediaries between the state and private owners.

Time frame

2014 – today

Key players

Land owners, municipalities as intermediaries and the state (Ministry for Housing) setting political targets and contracting external consultants. During the implementation of the programme, private and public landowners are and will be involved.

Implementation steps and processes

In 2014, the programme was initiated by the Ministry of Housing alongside other measures to revitalise housing construction and to address the shortage of housing in Luxembourg. Among these other measures are hereditary leaseholds, pre-emption rights for public actors, tax reform for housing, renting subsidies and ‘Baulandverträge’ (building land contracts).

Fictional example of the information brochure: the yellow ‘Baulücken’ provide the same surface as the red greenfield development. Source: Ministry of Housing.

The Ministry of Housing launched the programme, external consultants conducted the analysis and municipalities have to validate the results. Addressing private owners by providing information on the added value of the property and explaining the concrete advantages of mobilising specific lots should stimulate development. Public authorities should act as an interlocutor and advise owners to develop their property privately.

Experience from Germany has shown that information campaigns helped to convince 25% of private owners to develop their plots within the building perimeter.

Required resources

The process consists of multiple parts, so the resources required are unknown. The process is implemented by multiple actors with different motives and means, and thus estimating the required resources is not possible.


The ‘Baulückenprogramm’ has just started and has not yet provided additional tangible results. The analysis of the municipal building pattern to identify vacant lots has not yet been completed for all municipalities in Luxembourg.

Communicating the identified vacant lots to municipalities is realised through an online platform providing tailor-made access. A first pilot under the national vacant lot mobilisation programme is realised in Dudelange, in the south of the country. To develop the 0.4 hectares of land in Dudelange, a first call for tender for proposals was launched in 2016. The call was organised in cooperation with the Ministry for Housing and the municipality of Dudelange, incorporating the Fonds du Logement (the national Housing Fund). The winning concept Um Bierenger Haff proposes transforming the former farm into 16 apartments for families and single households. It keeps the rural character of the district and has multiple meeting places for new and old residents.

Facade of the new units at ‘Bierenger Haff’ in Dudelange. Source: Ministry of Housing, 2017.

Experience, success factors, risks

Mobilising private owners of vacant lots through information campaigns is decisive where land is privately owned and inaccessible for developing housing. It is also essential that public stakeholders lead by example by developing vacant lots on publicly owned land.

However, it remains to be seen whether the programme will be successful without financial incentives.


The first project Um Bierenger Haff in the framework of the national ‘Baulückenprogramm’ is a pilot to see how vacant lots can be used quickly without an excessive administrative burden. It is also the first opportunity to test the connection between different levels of decision-making and different economic rationales on matters of housing (private, municipal, state). The experience will help future mobilisation of vacant lots.


Ms Carmen Wagener, Ministry of Housing:

Ms Eva Gottschalk, municipality of Dudelange:


Ministry of Housing, Fonds du Logement, ville de Dudelange, 2017 – Concours “Baulücke” à Dudelange (in French):

Ministry of Housing, 2016: Lücke sucht Wohnung, neue Chancen für den Wohnungsbau (in German):

About 30% of land in the city of Luxembourg is owned by the municipality. Only about 246 of the publicly owned 1 600 hectares are classified in the local land use plan as building land, being connected to infrastructure and available for construction. With continuously increasing pressure on the housing market, the municipality is creating affordable housing for its citizens, through developing the ‘Baulückenprogramm’.

Rationale for action

Tackling the housing shortage is a key priority in Luxembourg overall, but especially in the capital, Luxembourg city, which is the main pole of attraction for people and businesses. By constructing affordable housing, the municipality can select tenants and owners from specific socio-economic groups. Developing vacant lots within the city can also avoid urban sprawl.

Houses built during the 1st iteration of the ‘Baulücken’ programme in 53-59, rue Schetzel.


The Luxembourg city ‘Baulückenprogramm’ uses vacant lots owned by the municipality to construct affordable housing. Developing such areas does not require long administrative procedures so construction can begin relatively quickly. More housing units can be created without developing land outside the existing urban fabric.

Time frame

There have been three rounds from 2006 to today (2021). The ‘Baulückenprogramm’ was first initiative of its kind in the country.

Key players

A joint working group of the municipality of Luxembourg (political players and municipal employees), Ministry of Housing and OAI (an organisation of architects and consulting engineers) organise the process and decide on proposals.

With the ‘Baulückenprogramm’, the municipality cooperates with private enterprises, architects and property developers. Developing concepts and plans for the vacant lots, while construction is organised through public procurement. Architects submit proposals for the housing design and private developers for the construction.

Implementation steps and processes

The ‘Baulückenprogramm’ is an umbrella term covering several implementation steps. The programme identifies vacant lots and implementation involves several rounds of planning and construction.

The municipality began identifying vacant lots based on information from satellite imagery, the land register and the local land-use plan. 73 potential sites were identified, for which district and individual records were created. Based on this information, the sites were presented to a working group, which selected the vacant lots to be developed.

The units are planned and realised in cooperation with architects and private real estate developers who build and sell the accommodation. The obligations and duties of developers are laid down in a contract with the municipality, clarifying the terms and conditions of transferring the units to future owners.

The units are allocated to residents through predefined selection criteria. A comprehensible and transparent checklist for each applicant allocates points based on individual socio-economic factors. A higher score indicates a greater possibility of being chosen as a future owner.

The selection criteria include the applicant’s age, family situation, working location and number of consecutive years lived in the city. There is a maximum score of 19 points (< 30 years of age, > 3 children, working in Luxembourg, living consecutively in the city for more than five years) and a minimum score of three points (> 45 years of age, no children, not working in Luxembourg, not living consecutively for more than five years in the city).

The units are sold through heredity leaseholds of 99 years. On a single lump-sum payment, the building land is transferred from the municipality to the developer (and finally to the future owner) and an annual user fee is required for the accommodation. Owners must personally reside in the units and cannot rent the property to a third person. The municipality also keeps a preemption right on all accommodation.

Apartment house built during the 2nd iteration of the ‘Baulücken’ programme in 1-13, rue des Forains.


The first round of the ‘Baulückenprogramm’ was in 2006 for nine vacant lots. Construction finished in 2010. The second round was initiated in 2010 for four lots, which was finalised in 2015. The last and current round started in 2013 for five lots and construction have been finalised in 2018.

During the first round (2006-2010), 75 accommodations were built including 18 single family homes. The second round created 58 apartments (2010-2015) and in the third round 64 units were completed in 2018. In all 197 accommodations have been realised through the ‘Baulückenprogramm’ so far. All units built during the first two rounds were sold to individuals. About half the accommodation in the third round will also be sold with the rest to be rented as social housing or affordable housing. All units follow state of the art building techniques and design principles.

Experiences, success factors, risks

The ‘Baulückenprogramm’ shows that municipalities in Luxembourg have an effective instrument to directly shape the supply of affordable and social housing. Emphasising building quality and design ensures residential buildings are integrated into their surroundings.

The programme was realised on vacant lots owned by the municipality. The majority of vacant lots in Luxembourg city are however owned by private individuals. The ‘Baulückenprogramm’ is a useful instrument to address the shortage of affordable housing in publicly owned areas. To mobilise private lots, other instruments and steps might be necessary.

Apartment house built during the 2nd iteration of the ‘Baulücken’ programme in 39bis, rue de Cessange.


The ‘Baulückenprogramm’ has seen the municipality pro-actively create affordable housing for residents. This enables the municipality to select future owners individually, offering affordable housing for specific socio-economic groups.


Urban development service,City of Luxembourg:


Presentation Ville de Luxembourg “Baulückenprogramm” (in French):