Britain's Imperial War Museum (IWM) recently gained a new archive to help house its vast collection of records, courtesy of Architype. The IWM Paper Store is one seriously energy efficient building and is also the most airtight Passivhaus project to date, according to International Passivhaus Association records.

The design of the IWM Paper Store is intended to complement the existing museum buildings on the site in Duxford, Cambridgeshire. Its simple box-like structure features a rusted steel facade with perforations that reflect the quantity of documents kept inside for different years.

The building measures 1,238 sq m (13,325 sq ft) and hosts collections of artworks, photographs, letters, and diaries that detail experiences of warfare from the 20th century to the present.

The building's high level of airtightness, combined with large amounts of high-quality insulation, means it will require very little energy to maintain a steady temperature inside. This isn't just good for the environment, but makes sound practical sense for storing documents safely too.

"To ensure the long-term preservation of the collections it is critical that the environmental conditions of the building remained very stable and well within the optimal tolerances for temperature and humidity," says Architype. "Traditionally this has been achieved through a finely tuned balance of complex building services. A Passivhaus strategy offered IWM an opportunity to use a low energy method that guaranteed stable environmental conditions for significantly lower running costs.

"The repository is the second completed Passivhaus archive (awaiting certification) for architects Architype, benefitting from lessons learned to produce a highly refined and efficient building. As such the new archive building boasts the world record for an airtightness result of 0.03 ach [air changes per hour]; as well as incorporating pioneering strategic differences from common structural approaches and design strategies."

The project also involved Fabrite and Momentum, and was constructed between December 2017 and January 2019 at a budget of £2,863,000 (roughly US$3.6 million).

Source: Architype

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