"It is a building of a single idea and not even necessarily a bad one, namely that every part - the steel structure, the polycarbonate cladding, the awnings, furniture, carpet and curtains - is coloured the same deep, blood red. The distribution of these elements is essentially church like, comprising a long nave, framed between lower side aisles, which terminates in an altar like box of red glass.....
In case we don’t get it, two words have been cut into the red film that has been applied to the glass at the back of the “altar”: GREEN, positioned at eyelevel and SKY close to the roofline. The effect is as underwhelming as it is leaden. The key problem is that the enclosure is far too partial to sustain the basic idea. Nouvel’s computer visualisations suggested a space that had the heady intensity of a photo lab but stepping into the pavilion one notices only the slightest change in light quality. (Are the gallery’s publicity photographs really free from the hand of Photoshop?)"
Further reading and Pictures of the Pavillion at bdonline