French museums are grappling with an increasingly critical storage crisis as their collections continue to grow while available space remains limited. A recent report by the International Council of Museums (ICOM) found that most surveyed museums evaluate their storage conditions unfavorably, particularly citing lack of space and inadequate equipment as major concerns.

The storage crisis has deep historical roots. In September 1994, a symposium on museum storage organized by the Musée des Arts et Métiers marked the beginning of extensive reflection on this issue. The symposium accompanied the museum's project for externalized storage in Seine-Saint-Denis, the first such project for a national museum, which remains an exemplary model today due to its impressive 8,000 square meters of space. Marie-Lys Marguerite, deputy director of the Louvre Conservation Center (CCL) in Liévin, describes these storage facilities opened in 1994 as "one of the models for all externalized storage facilities." The CCL itself spans 19,000 square meters, with 9,500 dedicated to storage.

The situation became so critical that in 2014, the Cultural Affairs Committee of the National Assembly studied French museums' conditions and dedicated an entire chapter to storage issues. Most recently, in 2024, ICOM devoted both a report and an international symposium to museum storage, highlighting the widespread nature of the problem. Museum storage facilities are no longer simple secure storage spaces – since the January 2002 law on museums, they have become integral parts of institutions' Scientific and Cultural Projects.

Space shortage represents the most frequently cited problem among museum directors and serves as a primary argument in both the 2014 parliamentary report and ICOM's findings. The 2014 report identified the constant growth of collections through acquisitions and the inalienability principle that prevents selling or disposing of artworks as key factors. Large donations compound the problem, as experienced at the Museum of Saint-Roch Hospice in Issoudun, where director Patrice Moreau noted a donation of monumental sculptures "that could not fit into the first saturated storage facilities." Similarly, Alexandre Estaquet-Legrand, director of the Mudo, Oise Museum in Beauvais, faces a comparable risk from a significant ceramics donation.

However, viewing storage facilities solely through the lens of space constraints would be reductive. These facilities also contribute to museums' conservation missions and mandatory decennial inventory requirements. Storage issues often resurface during major renovation projects or collection campaigns. Robert Blaizeau, director of the Metropolitan Museums Network (RMN) in Rouen, explained that "work at the Beauvoisine museum necessitated moving collections and reorganizing storage facilities," which led to a conservation center project.

Many museums face the problem of scattered storage across multiple locations. Before the CCL, the Louvre stored its collections in sixty-seven different storage areas within the museum itself and several warehouses in the Paris region. Numerous museums confront the costly problem of renting private storage facilities, primarily located in the Île-de-France region. The three Rouen museums affected by the Beauvoisine hub, housing 500,000 pieces, currently maintain several externalized storage facilities "including one in the Paris region," according to Blaizeau. During the 2000s, the National Museum of Modern Art rented storage facilities in northern Paris for 2 million euros annually, a cost highlighted in the 2014 report.

Conservation conditions for artworks can be particularly poor, especially in historic monuments where building constraints impose limitations. At Blois Castle, the Museum of Fine Arts maintains on-site storage facilities, some of which are inadequate. Director Bastien Lopez explained that furniture is "stored on the top floor of the François I wing, without an elevator." The Mudo, which has had external storage since 2015-2016, previously stored works under the roof of the Saint-Pierre wing of the episcopal palace, a section Alexandre Estaquet-Legrand described as "a real thermal sieve."

The numerous storage expansion projects reveal two strong trends: externalization and shared facilities. The 2014 report advocated for both approaches while acknowledging that museums are not equal in financial and logistical terms. Shared facilities offer numerous advantages, particularly financial ones. In France, 82% of museums are managed by local authorities, making it rational to gather local museum collections and conservation activities in one location. This approach has been adopted by Marseille, Nancy, Reims, Rouen, Tours, Strasbourg, and Rennes in recent years, as well as most cities with over 100,000 inhabitants.

In the Hauts-de-France region, where dozens of museums exist, storage sharing remains rare due to administrative oversight issues. A study by the DRAC Hauts-de-France on storage sharing, initiated alongside the CCL announcement, never materialized. Some metropolitan communities and departments have also chosen shared facilities, such as Quimper for Finistère museums in 2013, and the Nord Department for museums in four communes of La Porte du Hainaut in 2024.

National museums present a different case, as they have traditionally chosen to build their own storage facilities (Louvre, Mucem, Arts et Métiers). A recent exception involves the Centre Pompidou and the National Picasso Museum Paris, which partnered to construct storage facilities in Massy, included in a conservation center with cultural programming. Other museums adapt by creating spaces within their establishments or building small externalized storage facilities, such as the Museum of Pays de Cocagne in Lavaur.

Financial considerations remain central to these projects, which can cost several million euros. In Rouen, where storage facilities and the conservation center will cost 7 million euros, Robert Blaizeau reports no opposition from local officials, "even though a museum storage project doesn't bring immediate political visibility." Similar support exists in Issoudun, where Patrice Moreau notes that "the city supports the museum and provides the means to preserve collections." However, in Massy, the Centre Pompidou project faces criticism from the municipal opposition, which questions the financing arrangement where the city contributes 21 million euros out of 69 million total, while the building will belong to the state.

Financial costs sometimes force authorities to delay these projects for several years, with consequences for stored artworks and inconsistencies with museum policy. One way to make storage facilities profitable in officials' eyes is to open them for visits, but this conflicts with security requirements in buildings. The situation varies depending on whether storage facilities are located in new buildings (Reims) or converted old warehouses (Strasbourg museums).

The Mucem planned from its conception a 950-square-meter room within storage facilities to display selected works. Marie-Charlotte Calafat, scientific director and collections director, emphasizes that "any visitor can request to consult stored works in the reading room," similar to how libraries and archives function. This public opening requires "special arrangements, adapted circulation spaces, and presentation of objects in open cases." The Louvre's CCL is not open for visits except during European Heritage Days, since the nearby Louvre-Lens opens its storage facilities to visitors.

Storage facilities generally remain confined spaces because the atmosphere must be controlled (humidity, dust, mold, lighting, pests). Most storage areas are organized by materials and dimensions, with organic works and monumental pieces being naturally more complicated to preserve. At the CCL, the deputy director specifies that the large-format painting storage "was designed to accommodate the largest canvas preserved at the museum, Interior of Westminster Abbey in London, by Alaux" (66 meters by 19, stored rolled). In comparison, mineralogy or lapidary collections are simpler to preserve despite the number of pieces, as they don't require controlled climate conditions.

Conservators also focus on storage furniture and shelving types. Marie-Lys Marguerite explains that electrically movable shelves (compactus) minimize vibrations because their installation was integrated into construction lots with floor slabs. Patrice Moreau ordered "extractable painting grids of three by four meters specifically for large formats in the museum's first storage facilities" for the Museum of Saint-Roch Hospice. Robert Blaizeau cites the necessity of conducting floor load-bearing studies for very heavy loads (over 900 kilograms per square meter).

All facility directors emphasize the importance of packing and transit areas, which occupy space while facilitating handling in a context of multiplying temporary exhibitions. However, not all stored works and objects are intended for exhibition, and storage facilities also preserve objects for their scientific interest. Museum storage must therefore be organized to maintain balance between conservation, study, and valorization, ensuring these facilities serve multiple essential functions beyond mere space provision.