One of Chicago's most iconic buildings is to undergo yet another change. Not only is the Sears Tower is soon to be renamed the Willis Building but it will possibly be the biggest sustainability overhauls so far planned for an existing tower.
It's a theme that ties in with some of the recent thrusts of research the firm has done that look at rejuvenating supertall skyscrapers that are in danger of becoming obsolete but too tall to knock down easily.
The plans which have been drawn up by American architectural firm Adrian Smith + Gordon Gill will not only result in the tower reducing its energy consumption by a whopping 80%, but it also includes plans for a new 50 storey environmental hugging hotel tower which will stand on the south side of the sears plaza.
In order to reduce energy consumption and emissions from the existing tower a number of changes will be made including replacement of the towers 16,000 single paned windows and an upgrade of the buildings facades to create a thermal break which in itself would result in a 50% saving on heating energy used.
Mechanical systems will be upgraded to use the latest energy saving technologies along with an overhaul of the towers 104 high speed elevators. Light fittings will be upgraded and in places a state of the art lighting control system will be able to dim lights according to the amount of sunlight filtering into the building which will further reduce the amount of energy the tower uses.
Thanks to the towers design with its many set back roof spaces and its height it is also possible to add sky gardens that will be used for water filtration and improve insulation as well as provide extra amenities for the tower and solar panels and wind turbines could also soon be a feature of the tower.
The retail spaces and plazas will also be improved to include new glass facades, digital displays and terraced, tree lined public spaces to work as natural carbon filters.
The new proposed hotel, designed to achieve an LEED gold rating for sustainability will run of the Sears towers energy meaning it will draw zero energy from the power grid. The towers stands on a multi level podium consisting of several curving sections, the resulting stepped roofs of which will be used as green public spaces.
From here the oval shaped tower rises its peak which is topped by a glazed dome with integrated photovoltaic panels housing a solar deck which will offer stunning views of the city below, on various levels of the tower other large, open green spaces feature.
Featuring fully glazed facades the tower will have one of the first double skinned facades in the city, this will serve to trap solar heat which can be used in the winter while being vented in summer saving on air conditioning use. Using the towers curved shape, wind turbines will also be included on the facades to further generate energy for the tower.
The two towers will be linked by a glazed dome shaped walk way as well as terraced plazas, the 500 roomed hotel will include a ballroom, pools and spa and if approved could create an extra 3600 jobs in the area.