Hong Kong International Airport is one of three Skytrax 5-star airports around the world, and also the world’s busiest cargo gateway and one of the world’s busiest passenger airports.
The existing waterproofing system at Hong Kong Internation- al Airport Terminal 1 was found to be damaged. It consisted of 1.8 mm thick PVC membrane which was fixed on the composite roof decking by tie bars. The Hong Kong Airport Author- ity decided to install an additional waterproofing membrane on top of the existing system without removing the existing membrane in order to provide a durable new waterproofing system. The whole re-roofing project covered an area of 200,000 m2 with a target completion date in 2016.
The project included the design, supply and installation of an additional roof waterproofing membrane on the top of the existing PVC sheet membrane waterproofing system of Terminal 1 roof. The loading of the additional waterproofing system to be imposed on the roof was not to exceed 2.5 kg/m2, while its fixing system needed to satisfy the design wind pressure with the highest figure 8.5kPa. Moreover, seam welding was mostly done by handheld welding guns instead of automatic machines. This was due to the dome shape profile of the roof where automatic machine could not be implemented.
Sika Sarnafil® S 327-15 L was laid on top of the existing mem- brane by mechanically fastening it to the metal deck. The membrane was clamped by polymeric batten strip, Sarnarail and stainless steel fasteners. Sarnafil® Metal Sheet and Sikaflex® AT Sealant were installed along the roof edge pro- files and skylights. Sikaflex®-265 was applied to all skylight joints, totaling over 20,000 m of length. Sikaplan® Walkway was installed as maintenance protection.