Yang and his team ended up installing a steel girder to consolidate and straighten the beam.
He says he can still remember the dust that had accumulated on the beam over hundreds of years and how they had to blast it away when it was taken down for repair.
With surgical precision, Yang has given the drum tower a new lease of life.
"Bianjing Drum Tower is the work I'm most proud of," Yang says.
The project put Yang on the restoration map. His team has been invited to work on major historical structures at national, provincial and municipal levels.
Yang's two sons have also inherited the family tradition and followed in his footsteps.
In 2009, Yang and his sons led a team of workers back to the Yanmen Pass and worked on 1,800 meters of the Great Wall, upon which they also restored watchtowers and gate towers, as well as historical temples and a nearby folk village.
They finished the task in 2011, the same year the State Council listed "Yanmen folk house construction techniques" as a national intangible culture heritage.
Thanks to Yang's efforts, the Yanmen Pass scenic spot is one of the best culture and tourism destinations in the country and was classified as a top-rated national scenic spot in 2017.
Yang has shifted his focus to ancient architecture protection and inheritance, and has made a point of sharing his skills with more people beyond his family.
"As long as they want to learn, I'll hold nothing back," Yang says.
Half of the artisans in Daixian have been Yang's apprentices.
However, Yang has noticed a decreasing number of young people in his team.
"Most of them prefer modern trades," Yang says, adding that he hopes further support will be given to carry forward Yanmen house construction techniques.
Ji says he believes Yang's prayer will surely be answered.
The intangible culture heritage can be applied to a wide range of fields and help build the culture industry, which, in turn, will boost heritage development, Ji says. "The government will offer more support for its protection and utilization."
Peng Ke'er contributed to the story.
