The partners in the TriWaSol project want to contribute to making existing apartment buildings in the east of the Netherlands climate-adaptive and natural gas-free. The project focuses on technical aspects such as heat stress, noise nuisance and nuisance from excess rainwater in an urban environment. A smart combination of water and air heat pumps and retention roofs is used to improve energy performance and improve quality of life. The project also investigates how air-to-water heat pump systems can be made more efficient and quieter, and how water management and greening can be applied. TriWaSol is working with three companies, a housing corporation and the University of Twente to demonstrate this concept in an inhabited apartment building. With this new renovation strategy, TriWaSol aims to reduce both implementation costs and energy costs.