Text description provided by the architects. This project is a exhibition pavilion supported by Longfor Real Estate and Orient Sundar windows company, within which the sustainable architecture strategies and the edge-cutting building techniques could be introduced to the public.
The pavilion is located in a large green area along the river bank, where an urban park is plannedfor the public. On the south of the site, there is a dry pond, full of poplars. The first impression on visiting the site is the sunshine casting shadows among the trees, andthe starting point of the design work is to create a scene, in which the building could merge itself in the natural environment.
Meanwhile, the pavilion is targeted at the passive house certification. According to the PHI (Passive House Institute) standard, the building must be designed to have an annual heating demand as calculated with the Passivhaus Planning Package of not more than 15 kWh/(m2a);and the building must not leak more air than 0.6 times the house volume per hour (n50 ≤ 0.6 / h) at 50 Pa (0.0073 psi) as tested by a blower door. Those strict standards make a lot of limitation of building insulation, area of openings & windows, air tightness of windows & doors, thermal bridges, even the rational space form & shape coefficient. Those limitation made the design work not so free as usual.
During the whole process of the project, holistically sustainable design strategies are adopted in different levels of design.
In order to improve the heat performance, the north side of the building is sheltered with earth. The shape of the pavilion merges with the landscape topography, which make the pavilion's north facade completely vanished into the natural landscape. And the building’s thermal losses are highly reduced due to earth shelter in comparison with ordinary building insulation.At the same time, the south side is made with curtain wall, which could work as solar collector in winter for passive heating and as a mirror reflecting clearly the surrounding environment to extend natural landscape. In these ways, the north side of the building is hidden in the topographical landscape, and the south side of the building is hidden in the curtain walls' reflection of the trees and shrubs.
The design of the pavilion responds to the principal of sustainability. The inner space is low in the north and high in the south, which is correlated with the function distribution. The higher spaces are for exhibitions and the lower spaces are for service rooms and equipment room. The curtain wall, forming the whole south façade, could contribute to heat gaining in winter. While in summer, the sun-shading system functions automatically, tracing the orientation of the sunlight, preventing interior space from overheat.
The skylight in atrium brings the sunlight in daytime and will be opened for the natural ventilation at night. The fresh air system also takes advantage of the particular shape of the interior space, matching the thermal press ventilation principle. The fresh air outlets are set in lower spaces, such as the corridor area in the north, and the bottom of the seating stairs in atrium and the return air inlet are set in the top of the south, the highest point in the interior space.
The basic prototype of the pavilion is made of two wedges. A wedge-shape atrium is inserted into the main body. Besides the common exhibition route, the atrium also brings another route for visitors, which could create an experience for space of landscape. The terraced atrium, connecting the outdoor landscape with the interior spaces, blurs the boundaries between indoor and outdoor, ground floor and second floor, artificial environment and natural environment.
To create a more interesting experience in such a geometrically pure shape of building mass, two major artistic feature of traditional Chinese gardens are set in the design. One is “Varying sceneries with changing view- points", the other is "Borrow scene". The exhibition circulation begins from the Preface hall in southwest corner, moving clockwise around the house. On each turning point, there will be an Opposite scenery, to attract people's attention to move on. The rain water garden on northwest corner is a typical example. The window on the northwest corner is a relaxing place, which provides the buried exhibition hall an open landscape view of rain water garden. The rain water from the roof is led into the garden, irrigating the vegetation layer by layer, and mingling to the earth on the garden. The great steps in atrium shows more carefully planned of scenic views.
Looking From north to south, the viewpoint is high, over the square, to the woods, while from south to north, a path with wide opening and narrow ends blocks the view, where people have to climb over the steps, getting to the narrow ends with floor-to-ceiling windows and pass through it to the outdoor terrace, reaching the top of the landscape terrain. After that, there is a pathway which is embedded into the terrain. The corten steel sidewall cut the terrain in different depth, create a moving and changing view sight among the grass and flowers.
As a result, this project has been certified as passive house in design and construction by the Passive House Institute in Germany. It becomes the first PHI certificated exhibition architecture in Asia. The most important meaning for the design team is, the architectural design is not focused on the technical parameters or limited by the strict requirement of PHI, but to strive actively for creating a prototype of spaces with sustainable strategies and architectural interest.