A tree would live for hundreds of years while the timber buildings have much shorter life. Designing a city is also designing our forests. The projects aims to use digital tools to aid the labor process of the pre-treatment, after-care and transformation of timber. The building is a prototype in Shanghai, the alleys in the historical areas facing demolishment are transformed from horizontal to vertical town, inheriting the same spatial dialogue. The design system is inspired by the Theseus’s ship Paradox, timber elements from the old buildings will be examined and treated to be grafted into the new building system, where there would be both the uploaded digital twin and preserved physical bodies. That the identity is preserved as continuous state and the original matters. The structural part is designed with new CLT and Glulam, where the pre-treatment and inspection method are applied. The integral system seeking to extend the life of timber and joining the stories of the past and future.