Roof System of Asia’s Largest Civil Aviation Maintenance Hangar

The Hangar No. 1 at the new Beijing Daxing International Airport, operated by China Southern Airlines, is the largest maintenance hangar in Asia. The construction of this hangar utilized advanced technologies, processes, and materials, while also emphasizing environmental sustainability. Given the roof’s considerable height, large span, and minimal slope, the hangar’s roofing system required enhanced performance in waterproofing, fire resistance, insulation, and wind uplift resistance.

The roofing system for this project features a new TPO (Thermoplastic Olefin) single-ply roofing system. The waterproofing layer consists of 1.5 mm thick Soprema polyester fiber-reinforced backing nonwoven TPO membrane, which is fixed using a combination of mechanical fastening and adhesive methods. The insulation layer is made from Foamglas foam glass insulation boards, equipped with a specialized fiberglass facing, offering Class A fire resistance.

In contrast to the commonly used single-ply roof system in China, which comprises a load-bearing steel plate, rock wool insulation board, polyethylene vapor barrier, and waterproofing layer, this project employs a load-bearing steel plate, insulation layer, and waterproofing layer with a tightly connected, cavity-free system. This configuration results in a comprehensive roofing system with a thickness of 150 mm.

Waterproof Performance:

The fully adhered method used to bond the waterproofing membrane to the insulation layer ensures high-quality waterproofing. The TPO membrane used in this project has high welding strength and excellent waterproofing performance, effectively ensuring overall waterproof functionality. Additionally, the TPO membrane is fully adhered to the foam glass board, which itself is non-absorbent, creating a multi-layered waterproof barrier that significantly improves system performance. This setup overcomes common issues of water penetration and leakage found in traditional single-ply roofing systems and effectively addresses condensation problems.

Vapor Barrier Insulation Effectiveness:

The foam glass board, made from glass, does not absorb water and features a 100% closed-cell structure, eliminating capillary action and completely blocking moisture vapor. During installation, sealant is applied to the seams of the foam glass boards, which not only prevents the migration of moisture and air but also reduces heat loss.

Durability and Longevity:

The TPO membrane used in this project is highly durable, with a certified lifespan of up to 30 years by BBA (British Board of Agrément) and wind uplift and fire resistance certifications from FM (Factory Mutual). The membrane’s nonwoven backing enhances adhesion and reduces damage from uneven substrates and long-term contact with fasteners. Furthermore, the foam glass insulation boards are characterized by high strength, non-compressible deformation, and resistance to moisture and decay, ensuring that the roof system’s waterproofing and insulation performance remain stable and reliable over time.

System Safety:

The spacing of the TPO membrane fasteners in this roofing system has been verified through theoretical calculations and wind uplift tests, with actual installation carried out at a density of 1.98 meters by 0.1 meters. Considering the profile of the corrugated steel base plate, a 0.8 mm thick steel plate was added in the fastening areas to facilitate the installation of the membrane. Professional wind tunnel testing has confirmed that this fully sealed adhesion system, combining the waterproofing and insulation layers, significantly enhances the overall wind uplift resistance of the roof.