1. Project Information
The Beijing China Resources Building is located in the Central Business District approximately 500 meters northwest of the Jianguomen Overpass. It is adjacent to the Second Ring Road in the east, Chang'an Avenue in the south, Jinbao Street in the north, and Jinyin Street in the west. Covering an area of 13,000 square meters, it has a total floor area of 71,054 square meters. The building has 29 floors and a height of 99.7 meters, making it the tallest building within the Second Ring Road of Beijing at that time.
After the building was put into use in August 1999, leakage problems gradually emerged, affecting the normal use of the tenants. In 2006, the property owner decided to carry out roof waterproofing maintenance. After selection and comparison, the Sika PVC single-layer roof system was finally chosen, and the waterproofing renovation construction started on May 1st, 2006.
Before the waterproofing renovation of the China Resources Building, the basic layers of the roof were: ceramic tiles, cement mortar, insulation layer, waterproof layer, ceramsite slope-making layer, and structural layer. The original waterproof layer was made of asphalt waterproofing membrane, which had aged, and the concrete protective surface layer had cracked, losing its waterproof function. Due to the ceramic tiles laid on the roof, it was difficult to find the leakage points, and local maintenance was challenging. Moreover, there were many detailed nodes on the roof and protruding components, and ordinary waterproof materials and construction techniques were difficult to achieve long-term, environmentally friendly, and reliable waterproofing effects.

2. Roof Renovation Process
Because there were ceramic tiles on the roof, it was difficult to find the leakage points, and local maintenance was challenging. Additionally, there were many detailed nodes on the roof and protruding components, so it was finally decided to carry out a comprehensive waterproofing renovation. Before the waterproofing construction, all the existing roof tiles, ceramsite slope-making layer, the original waterproof layer, etc. were completely cleaned to the roof concrete base layer, and the damaged parts of the concrete base layer were repaired. The Sika PVC membrane was fixed to the roof concrete base layer using the mechanical fixation process. The model of the waterproofing membrane used was Sika Sarnafil F10-15F, and the model of the adhesive used was Sarnacol 808 adhesive. For the parts that are frequently accessed for inspection by people, Sika's special PVC anti-slip walkway panels were laid and installed after the membrane construction. The entire waterproofing construction process was carried out without open fire and was a cold construction method.
The specific layers of the roof repaired with PVC membrane are as follows:

3.   Project Summary

The roof waterproofing renovation was completed on June 1st, 2006. On August 23rd, 2023, Beijing Guzhuo conducted a roof follow-up visit 17 years later. As the core management personnel of the original waterproofing renovation project, through on-site inspection and the actual feedback from the property management personnel of the building, we learned that the roof waterproofing of the China Resources Building in Beijing has been in good condition so far and there has been no leakage in 17 years. This follow-up visit confirms the feasibility, reliability, and safety of the application of the Sika PVC single-layer roof system in the waterproofing of high-rise building roofs.

1) The Sika PVC membrane has excellent weldability and physical properties, effectively ensuring the continuity of the waterproof layer, its compatibility with the base layer, and the convenience of subsequent maintenance and service.

2) The Sika PVC waterproofing membrane has excellent anti-aging and anti-ultraviolet properties, and has a BBA certification for a service life of up to 35 years. The white surface and self-cleaning function endow the membrane with high solar reflectivity and energy-saving effects.

3) Excellent materials require higher requirements for construction control and detail handling. A professional, reliable, and responsible engineering company is crucial to the success of the project.