Beijing Horticultural Expo (Int'l Pavilion)

Background

The International Pavilion of the 2019 Beijing International Horticultural Exhibition, located in the core exhibition area in Yanqing District, Beijing, is one of the Expo’s landmark buildings. Its design concept, inspired by “flower umbrellas,” features 94 large steel structures forming a complex, multi-curved roof with numerous skylights, vents, and equipment bases at varying heights. As a key venue for global exhibitors and visitors, the International Pavilion demanded extremely high reliability, durability, and aesthetics from its waterproofing system. The roof had to withstand rain, snow, and ice loads while coping with Beijing’s summer heat, winter cold, and intense UV radiation. The basement level, housing equipment rooms and exhibition support spaces, faced long-term moisture exposure and potential structural settlement, making conventional flat waterproofing methods inadequate.

Solution

The roof renovation utilized KIN TARPO DR TPO waterproofing membrane, while the basement employed KINJOYA FM PLAIN SBS waterproofing membrane, with distinct strategies for each area. Before roof construction, 3D scanning and modeling of the curved substrates of the 94 “flower umbrella” steel structures were conducted. Custom fan-shaped membrane cutting plans were developed from the model data to ensure perfect adhesion of each TPO sheet to the curved surface, minimizing seams. For the connections between skylights and the steel structure, a triple sealing system of “TPO membrane + metal batten + sealant” was applied. For the basement, considering potential settlement, a cold primer was applied before the SBS membrane was fully adhered, with seams welded via heat fusion to create a continuous layer. Additional SBS layers were installed at internal and external corners for reinforcement.

Outcomes

Since the Expo’s opening in 2019, the waterproofing systems for the roof and basement have remained stable for over five years, with no leaks. The KIN TARPO DR TPO membrane on the roof shows no significant aging, cracking, or discoloration under long-term UV exposure, maintaining its flexibility and integrity, effectively resisting structural deformation during winter. The complex roof and detail treatments have withstood numerous heavy rains and snow accumulation without leaks, safeguarding the exhibition spaces and equipment inside. The KINJOYA FM PLAIN SBS membrane in the basement remains firmly bonded without blistering or delamination, effectively preventing groundwater infiltration and ensuring reliable operation of the equipment rooms and auxiliary spaces.