As the contemporary ecological architecture movement gained momentum, an architectural movement formed that was diametrically opposed to it. Since the 1960s, a massive growth in concrete buildings has occurred, with construction consuming significant amounts of water and fossil fuels. Brutalist and modernist architectural forms are no longer as fashionable as they were between the 1960s and 1980s, and green features conceal and modify their harsh aesthetics.Architects are becoming more concerned with quantifying and mitigating the environmental impact of the buildings they construct. The word “ecological architecture” gradually appears in the vision of the architects. The buildings we make are becoming more and more " environmentally friendly", "sustainable" and "ecological". We even have a rating system such as LEED. Although LEED and Energy-Star are commendable, they are incomplete. These scorecard techniques do not match design practice. The LEED credits do not offer design direction or evaluation on the effectiveness of a design choice. Rather, they present a set of dos and don'ts for the design process. Architects seek strategies to determine the environmental effect of both the entire building and individual design choices. Many architects or architectural firms rigidly try to make the buildings they design sustainable or environmentally friendly. They rigidly integrate architecture and nature, whether through the use of green walls on individual structures or the incorporation of green spaces into urban plans. Yes, these buildings meet LEED standards, but they are very superficial. What is a real sustainable building, and a real ecological building? A true eco-architecture should be a “Loop”. Loop can be understood from a superficial perspective as a cycle, where the beginning is the end. The cycle also means that when a substance loses its own properties, it becomes another substance that exists in the world, in a way that is understood like the feeling of reincarnation in religion. In nature, substances die, degrade, turn into other substances, or become catalysts for the creation of certain substances. There is a Chinese poem that says, “落红不是无情物，化作春泥更护花” which means: Fallen petals are not heartless matter, Transmuted into spring soil they will again nurture flowers. Therefore, I think the again nurture flowers. Therefore, I think the real ecological architecture should be like the loop in nature, the building must not be able to do the real standing, we should think about the life span of the building, when the material life span is exhausted, what can the building become. Therefore, I think architects need to think about this issue from three aspects: material, space, and the role of architects. Materials as a “Loop”, a new way of using materials wisely for the whole earth ecosystem, not only building with reused, renewed, and recycled materials, but also using some emerging materials to protect the environment. Space as a “Loop”, a new space, not only adds a natural element to the space, the space itself is nature, and the key to nature is that everything is a cycle of cycles. Architect as a “Loop”, a new way of designing buildings, takes a completely new perspective on these buildings. Architecture is no more a machine but a life form. The lifecycle of the building is also part of the loop, from where the materials came from to design, and what kind of posture the building presents to people when the material lifespan ends, all these need to be thought of and designed by the architect. The essays will star from this three directions to discuss all the projects I designed in Cornell University to illustrate Designing Building as a Loop.