seele built the new roof on the existing steelwork to the atrium and closed off the open sides with glass cable-net façades. These comply with high energy-efficiency requirements and the museum’s special lighting specification: no UV light and a high level of daylight with natural colour rendering. Computer simulations enabled condensation scenarios to be studied. The results of the simulations governed the design of the glazing: double and triple glazing and at particularly exposed places a low E-coating as well. This faithful response to the particular conditions in situ reliably prevents condensation collecting on the inside of the panes.
A constructional trick was also necessary for transferring the wind loads: Horizontal cable backstays absorb a large part of the wind load and therefore enable a very slender cross-section for the vertical steel sections, which are just 120mm x 60mm.
The work to the end blocks was also exceptional. Completely prefabricated, including the glazing, they were delivered in containers and lifted into position on the façade by crane. Stepped insulating glass units combined with structural silicone joints produce a flush appearance that harmonises well with the large-format stone slabs.
Header image, 1st, 2nd & 3rd slide image © Museum of Fine Arts
4th, 5th & 6th slide image © Nigel Young / Foster + Partners