屋頂城市化—萬能視角建筑學(五)

朱文一

1 屋頂城市化與萬能視角建筑學

屋頂城市化（Rooftop Urbanism）意指通過再設計的方式將被忽視、被廢棄、被物所占據的建筑屋頂轉變為具有相應空間品質的屋頂。城市化后的地方被稱為城市或城區。城市中的建筑應該都是城市化的，屋頂是建筑的一部分，為什么還要提“城市化”？事實上，仔細分析城市化的狀況，就會發現城市中供居民和游客使用的空間沒有想象中的多。城市中相當多的地方是閑人免進的、禁止入內的，也就是不可達的。例如，在不少現代城市中，許多建筑屋頂往往被設施、設備占據，沒有被城市化。在谷歌地球衛星地圖上萬能視角下，甚至在現代城市的中心區，未城市化的建筑屋頂比比皆是（圖1）。屋頂城市化，構成了“萬能視角建筑學”理論第五篇文章的主要內容。

再來談談萬能視角建筑學。在過去4 年中，我先后發表了萬能視角建筑學（一）至（四）4 篇系列文章[1-4]，分別討論了萬能視角優先、城市地標的扁平化設計、城市地標二維碼設計以及萬能視角建筑學理論術語等內容。最后一篇文章針對34 個相關名詞進行了梳理和再定義，簡要總結了萬能視角建筑學理論的基本理念和方法。萬能視角優先，這是萬能視角建筑學的出發點。它在虛擬空間中實現了以萬能視角優先體驗建筑獲得完整空間體驗。在萬能視角優先下，與北京老城優美、錯落、協調的建筑坡屋頂相比（圖2a,圖2b），不少現代城市丑陋的第五立面可以用“荒蕪的地表”來形容。萬能視角優先下，甚至在現代城市的中心區呈現出如同城鄉交接帶一樣的廢墟景象。這一方面表明過去的城市與建筑發展中設計的缺席，至少忽略了萬能視角下建筑屋頂的設計，另一方面也為未來的城市更新與可持續發展提供了 空間。

圖1 / Figure 1萬能視角下的當代城市Contemporary City through God's-Eye-View

本文從屋頂建筑化（Rooftop Architecture）、屋頂公共化（Public Rooftop）和屋頂公園化（Rooftop Park）等方面，論述了當今城市屋頂城市化的必要性，探討了在萬能視角下通過屋頂城市化進一步提升城市空間品質的一種路徑。

2 屋頂建筑化

屋頂建筑化（Rooftop Architecture）是指通過再設計的方式，將設施設備的屋頂變成人活動的屋頂；在工程師所做的屋頂的基礎上添加建筑師設計的屋頂。這不是替代關系，而是“屋頂+”。如果在建筑設計過程中，建筑師已經設計了屋頂，那么可以認為這幢建筑屋頂已經城市化了。如果在建筑設計過程中，建筑師忽略了屋頂，那么這幢建筑就需要進行屋頂再設計，即“屋頂+”。

不少現代城市方盒子建筑林立，被各種設施、設備占據的功能性屋頂隨處可見。在寸土寸金的城市中心區，這樣的現象依然存在。中心區地價如此昂貴，被設施設備占據的建筑屋頂顯然沒有體現其價值。動作片電影導演應該是最早看到城市中心區建筑屋頂再利用潛力的一類人。他們將極限打斗場景從過去郊外廢棄的船廠等破爛場所搬到城市中心區建筑屋頂上同樣破敗不堪的場所，并且還創造了在同一個地方現代文明與叢林野蠻、摩登時尚與破爛廢墟產生強烈對比的視覺效果。

從專業的角度看，不少建筑屋頂被結構、水、暖、電專業的設施和設備占據，除了極少數檢修工人之外，這里幾乎是城市人口密集區中的“無人區”。換一句話說，現代城市中多數方盒子建筑的屋頂普遍存在建筑師缺失的狀況，成為建筑設計的盲區。今天，非常有必要以建筑與城市設計視角重新審視建筑屋頂。建筑屋頂再利用，特別是城市中心區建筑屋頂的再利用，將建筑屋頂上那些被設施設備占據的地方釋放出來，變成城市公共空間的一部分，已經成為提升城市空間品質不可回避的議題。針對大型商場、辦公樓以及大型交通建筑等不同建筑的屋頂，屋頂建筑化有不同策略。

多數大型商場的屋頂處于廢棄狀態(圖3），特別是城市中心區的大型商場，屋頂建筑化的必要性和迫切性大大加強。將這樣的屋頂再設計為以室外為主體的公共空間，既能更好地滿足中心區的使用需求，又直接提升了城市空間的品質。大量辦公樓建筑的屋頂也處于廢棄狀態（圖4）。針對上班族白天8 小時上班的地方，可以將辦公樓屋頂再設計為觀景平臺，并配置咖啡等室外休閑場所。城市中的大型交通樞紐（圖5）往往位置極佳、占地巨大，同時又有最佳的可達性，但現狀的建筑屋頂往往是巨大的不能上人的巨型頂蓋。是否可以探索將局部屋頂再設計為公共休閑觀景平臺，進一步提升建筑空間的品質。

以萬能視角優先的思路設計建筑，建筑屋頂不僅被充分考慮，而且成為建筑的“正立面”（圖6）。這樣的設計不存在屋頂建筑化的問題。

3 屋頂公共化

屋頂公共化（Public Rooftop）是指將城市中建筑的屋頂向居民和游客開放。隨著城市的不斷發展，人們對城市公共空間的需求也相應增加。然而，城市公共空間用地是有限的、不可再生的稀缺資源。提倡屋頂城市化，為進一步發掘城市中的公共空間資源提供了一種可能。

本文主要討論的是由方盒子建筑構成的現代城市。在這樣的城市中，一般都有少數帶有觀景臺的高層建筑、構筑物或自然山頂作為公共空間對公眾開放。絕大多數建筑的屋頂都具有建筑化的潛力。在此要強調的是，屋頂公共化就是要鼓勵更多的建筑屋頂不僅要實現建筑化，而且還要追求更多公共化。

圖2a / Figure 2a今天的老北京城The Old City of Beijing on Satellite Map

圖2b / Figure 2b電影《邪不壓正》中的老北京城 / Image of the Old City of Beijing in Movie Hidden Man

政府政策支持是屋頂公共化的一種策略。具體地說，針對大型商業綜合體，政府政策獎勵，鼓勵業主重新設計和改造屋頂空間，創造對外開放的屋頂空間。這樣的方式不僅可以創造更多開放的城市觀景平臺，而且還可以提升大型購物中心的購物體驗。針對城市中心區辦公建筑，政府通過特殊政策支持，鼓勵業主重新設計并開放屋頂空間，增加辦公樓區公共服務功能，提升辦公建筑環境的整體品質。針對城市中的住宅樓，鼓勵開發商選擇部分可達性較強的住宅樓建筑，在符合法規條件下進行屋頂再設計，將社區中心的部分功能放置在住宅樓的屋頂，提升社區空間的品質。

屋頂公共化旨在挖掘城市中那些有潛力變成公共空間的建筑屋頂，一方面可以大大增加城市中公共空間的數量，并與城市中已有公共空間相連接，形成整體的城市公共空間體系；另一方面，還可以增加公共空間的類型，創造“城市剖面”豎向城市空間形態，形成向居民和游客開放的城市天際線。而在萬能視角優先下的設計中，可以將建筑主入口設計在屋頂上，達到建筑屋頂公共化的最大化（圖7）。

4 屋頂公園化

屋頂公園化（Rooftop Park）是指在城市中盡可能多的建筑屋頂上進行植物和花草等種植，形成屋頂花園。公園是滿載人類情感的空間形式在城市中的投射，是人類理想聚居模式在城市中的體現。一百年前，埃比尼澤·霍華德提出的花園城（Garden City）所詮釋的城市與自然關系至今依然是人類城市追求的目標，而勒·柯布西耶的建筑屋頂花園構想則在建筑層面呈現了建筑與自然關系。與自然和諧融合的城市和建筑是人類追求的理想。在現實的城市中，這樣的美好愿景只能在公園這樣在城市中占比很低的空間形態中體現?？梢哉J為，公園是實現城市美好愿景的初級階段。

在現代城市中，比公共空間還要難以發掘的是城市綠地空間。過去幾十年大力提倡的綠色建筑設計和生態城市建設，已經為城市增加了盡可能多的綠色。本文提出的屋頂城市化則為大幅度增加城市公園提供了新的路徑。理論上，現代城市中方盒子建筑的屋頂都是可以公園化的?？梢哉w清理廢棄屋頂進行種植，在屋頂上創造具有一定規模的空間花園；可以在屋頂設施之間，“見縫插針”進行種植，在屋頂上形成由零散種植構成的花園；還可以在屋頂設施上方加建一層輕型結構，通過加法增加綠色空間。

在墨爾本未來公園設計國際競賽中，朱文一工作室提交的“墨爾本屋頂公園2050”設計方案探索了在墨爾本城市中心創造未來屋頂公園新形態的可能性。在研究墨爾本城市空間發展的基礎上，方案選定墨爾本現有的公園為地段，并將其向西邊的方盒子建筑為主體的商務中心區擴展，設計1.8km×1.8km 方形的全新形態城市公園。在這座公園中，具有歷史文化價值的公園、體育運動公園等現有的地面標高上的城市公園占不到40%面積，其余60%的公園將按照設計在未來30 年中在方盒子建筑屋頂上逐步實現。這是地面公園和空中花園相結合形成的全新公園形態，也成為屋頂公園化的首個案例（圖8a，圖8b）。

屋頂公園化是一種設計理念，也是一種設計方法。它可以應用在同樣呈現方盒子建筑荒蕪地表的城市中心區，如東京、上海、成都等城市中心區，當然還有方盒子建筑摩天樓林立、荒蕪地表最集中代表的紐約曼哈頓中央商務區。

5 大中央公園構想

圖3 / Figure 3大型商場荒蕪的第五立面The Fifth Facade of Shopping Malls

紐約中央公園（Central Park），這座完全的人造自然景觀，由美國景觀建筑師弗雷德里克·奧姆斯特德（Frederick Law Olmsted）和卡爾波特·沃克斯（Calbert Vaux）于1858 年設計。中央公園被稱為紐約“后花園”，以59 街（59th St.）、110 街(110th St.)、5 大道(5th Ave.)、中央公園西部路(Central Park West)圍繞，南北跨越51 個街區，長達4,000m，東西橫跨3 個街區，寬800m，占地面積340ha（圖9a）。中央公園不僅是景觀園林的杰作，城市與自然和諧關系的楷模，更是一個從過去到現在直指未來的神奇存在。150 年前的中央公園喻示著未來城市公園化的趨向。

圖4 / Figure 4辦公樓頂上布滿設施的建筑屋頂Rooftop of Office Buildings Occupied by equipments

朱文一工作室2019 年8 月完成的屋頂城市化研究性設計方案“大中央公園”（Greater Central Park），探索了從曼哈頓中央公園到曼哈頓公園城市的可能性。方案在現狀中央公園的基礎上，將其向東擴展3 個街區至第2 大道，向南延伸50 個街區至6 街；創造4 倍于中央公園，面積達1,360 公頃的大中央公園（圖9b，9c）。方案建立在屋頂公園化的設想基礎之上。曼哈頓中心城是中央商務區高樓林立形態的原型，方盒子高層建筑的匯聚地。中央公園東面的高檔公寓區同樣以方盒子建筑為主體。也就是說，在大中央公園劃定的范圍內，除了少量地標建筑之外，為數眾多的方盒子建筑都存在屋頂城市化、屋頂建筑化、屋頂公園化的巨大潛力。紐約有非常成熟的城市治理體系，特別在區劃、城市設計導則方面一直引領世界城市的發展；紐約又是未來城市的實驗室，引領世界城市發展的設計方案、設計實踐案例層出不窮。盡管大中央公園只是設計構想，仍然可以想象，在未來幾十年間逐步形成的大中央公園（圖10），可以將曼哈頓整體實現花園城的愿景向前推進一步；同時也將屋頂城市化的理念散布至世界城市的中心區。

本文提出的屋頂城市化直接針對當代城市發展、城市空間品質提升、城市改造更新等議題。這是萬能視角建筑學理論系列文章的第五篇，萬能視角優先是屋頂城市化的先導。如同萬能視角建筑學（I）文章中提到的，萬能視角建筑學也可以稱之為谷歌地球建筑學。通過谷歌地球提供萬能視角優先的衛星地圖，還可以發掘更多城市空間發展的議題。

圖5 / Figure 5大型交通樞紐的屋頂Rooftop of Mega Structure Terminal

圖6 / Figure 6 Plan O方案中，屋頂作為建筑正立面設計Rooftop as Main Facade of the Proposal Plan O

圖片來源：朱文一工作室 www.zhuwenyi.com

圖7 / Figure 7赫爾辛基大臺階上的入口Entrances on Rooftop from Proposal Helsinki Steps

圖片來源：朱文一工作室 www.zhuwenyi.com

1 Rooftop Urbanism and God's-Eye-View Architecture

Rooftop Urbanism means to redesign neglected, abandoned and occupied building rooftops into rooftops with better spatial quality through redesign. The place after urbanization is called a city or an urban area. The buildings in the city should be urbanized. The roof, as part of the building, must be urbanized. Why do we mention "rooftop urbanism"? In fact, by analyzing the current state of urbanization, it is found that the space used by residents and tourists in the city is not as much as imagined. A considerable number of places in the city are forbidden to enter, that is, unreachable. For example, in many modern cities, many building's rooftops are often occupied by facilities and equipment where are not urbanized. Under the God's-Eye-View on Google Earth satellite map, even in the central area of modern cities, unurbanized rooftops abound (Figure 1). Rooftop Urbanism is the main content of the fifth article of the God’s-Eye-View Architecture theory.

Let's talk about the God's-Eye-View Architecture theory. In the past four years, I have published a series of four articles (1) to (IV) of the God's-Eye-View Architecture theory[1-4], respectively discussing the God's-Eye-View first, the flat design of urban landmarks, the urban landmark QR code design, and The terminology of God's-Eye-View Architecture Theory and so on. The last article redefines 34 related nouns of the theory, and briefly summarizes the basic concepts and methods of the theory. The God's-Eye-View is preferred, which is the starting point for the God's-Eye-View Architecture theory. It realizes a complete experience of architecture in the virtual space with God's-Eye-View. Under the God's-Eye-View first, compared with the beautiful slope roof of the old city of Beijing (Figure 2a, 2b), many of the ugly fifth facades of Buildings in modern cities can be described as "ridiculous surface". This indicates that the absence of design in the past urban and architectural developments at least neglects the design of the building roof from God's-Eye-View； on the other hand, it also provides space for future urban renewal and sustainable development.

From the aspects of Rooftop Architecture, Public Rooftop and Rooftop Park, this paper discusses the necessity of rooftop urbanism today, and discusses the further urbanism through rooftops from God's-Eye-View, A path to improve the quality of urban space.

2 Roof Architecture

Rooftop Architecture refers to the redesign of the roof of a facility into an active roof； an architect-designed roof is added to the roof of the engineer. This is not an alternative relationship, but a "rooftop +". If the architect has already designed the roof during the architectural design process, then the roof of the building can be considered urbanized. If the architect neglects the roof during the architectural design process, then the building needs to be redesigned for the rooftop, "Rooftop +".

圖8a / Figure 8a墨爾本屋頂公園方案總圖Master Plan of Proposal Melbourne Rooftop Park

圖片來源：朱文一工作室 www.zhuwenyi.com

圖8b / Figure 8b墨爾本屋頂公園方案Proposal Melbourne Rooftop Park

圖片來源：朱文一工作室 www.zhuwenyi.com

Many box buildings in modern cities are built, and abandoned-like rooftops occupied by various facilities and equipment can be seen everywhere, even in the city center. The land price in the central area is so expensive that the building rooftop occupied by the facilities and equipment is not in line with its value. The action film director would be the first to see the potential of building rooftop reuse in the city center. They moved the extreme fighting scene from the ruined sites of abandoned shipyards in the past to the equally dilapidated sites on the rooftop of the city center, and created a strong contrast between modern civilization and jungle barbarism, modern fashion and ruined ruins in the same place.

From the perspective of professional fields, many building rooftops are occupied by structures, water tanks, heating and electric facilities and equipment. Apart from a very small number of maintenance workers, it is almost a “no man's land” in downtown area. In other words, there is no architects who cares about the building rooftop of most box buildings in modern cities. Today, it is very important to rethink the building rooftops from the perspective of architecture and urban design. Reuse of building rooftops, especially the reuse of building roofs in city centers, has become an unavoidable issue in improving the quality of urban space. There are different strategies for rooftop redesign of different buildings such as large shopping malls, office buildings and large transportation terminals.

The rooftops of most large shopping malls are abandoned (Figure 3). Especially in large shopping malls in the downtown area, the rooftop architecture has been more necessary and urgent. Redesigning such a rooftop into a public space not only better meets the needs of the downtown area, but also directly improves the quality of the urban space. The rooftop of a large number of office buildings is also abandoned (Figure 4). For people who work 8 hours a day during the day, the rooftop of the office building can be redesigned as an observation deck, and outdoor relax places such as coffee can be arranged. Large transportation hubs in the city (Figure 5) tend to be in an excellent location, occupying a large area, and at the same time having the best accessibility. But the building rooftop is often a huge giant canopy that cannot be used as a public area. Whether it is possible to explore the redesign of a partial roof as a public places.Designed with God’s-Eye-View first, the building rooftop is not only fully considered, but also the "main facade" of the building (Figure 6).

3 Pubic Rooftop

Public Rooftop refers to opening the roof of a building in a city to city residents and tourists. As the city continues to develop, so does the demand for urban public space. However, the land for urban public space is a limited, non-renewable resource. Making more public rooftop provides a possibility to further explore the public space resources in the city.

This article focuses on modern cities made up of box buildings. In such cities, there are usually a few high-rise buildings, structures or natural hilltops with observation decks that are open to the public as public spaces. The rooftops of most buildings are potential to be public Rooftop. It should be emphasized here that the public Rooftop is to encourage more building rooftops not only to become architecture, but also to pursue more public Spaces.

圖10/ Figure 10分階段實現大中央公園計劃Implementation of Greater Central Park step by step

圖片來源：朱文一工作室 www.zhuwenyi.com

Government policy support is a strategy for the public rooftop. Specifically, for large commercial complexes, government policy incentives encourage owners to redesign and renovate rooftop spaces to create open roof spaces. This way not only creates more open city observation decks, but also enhances the shopping experience of large shopping centers. For the office buildings in the city center, the government can encourage the owners to redesign and open the rooftop space through special policy support, increase the public service area of the office building, and improve the overall quality of the office building environment. For residential buildings in cities, developers are encouraged to select some of the most accessible residential buildings, and redesign the rooftop under regulatory conditions, placing some functions of the community center on the rooftop of the residential building to improve the quality of the community space.

Public Rooftop aims to tap the Building rooftops in the city that have the potential to become public spaces. On the one hand, it can greatly increase the number of public spaces in the city and connect with the existing public spaces in the city to form an overall urban public space system； On the other hand, it is also possible to increase the type of public space, create a "urban vertical public spaces", and form a city skyline that is open to city residents and tourists. In the design with the God’s-Eye-View first, the main entrance of the building can be designed on the rooftop to maximize the public spaces of the building rooftop (Figure 7).

4 Rooftop Park

Rooftop Park refers to the planting of plants and flowers on as many roofs as possible in the city to form a rooftop garden. The park is the embodiment of the ideal settlement pattern of human beings in the city. A hundred years ago, the relationship between the city and nature explained by Garden City by Ebenezer Howard is still the goal pursued by human cities, and Le Corbusier's rooftop garden concept of new architecture. Cities and buildings that blend harmoniously with nature are ideals for human pursuit. In a real city, such a beautiful vision can only be reflected in a spatial form such as a park that has a low proportion in the city. It can be argued that the park is the initial stage of realizing the city's vision.In modern cities, it is more difficult to discover than the public space is the urban green space. Green building design and eco-city practice, which have been strongly promoted in the past few decades, have added as much green as possible to the city. The rooftop urbanism proposed in this paper provides a new path for the substantial increase of urban parks. In theory, all of the box-building rooftops in modern cities can be parked. The abandoned rooftop can be cleaned as a whole for planting, and a garden with a certain scale can be created on the rooftop； it can be planted between the facilities on the rooftop, forming a garden composed of scattered plants on the rooftop, creating a light structure and add green space by adding.

In the Melbourne Future Park Design International Competition, the "Melbourne Rooftop Park 2050" design proposal by ZHUWENYI Atelier explored the possibility of creating a new form of future rooftop park in the heart of Melbourne's city centre. Based on the study of Melbourne's urban space development, the proposal selected Melbourne's existing park as a lot and expanded it to the west side of the box building as the main business center area, designing a new typology of city park, a square park with 1.8km×1.8km. In this park, the existing urban parks with historical and cultural values such as parks and sports parks account for less than 40% of the area, and the remaining 60% of the parks will be designed on the box-building rooftops step by step in the next 30 years. This is a new form of park formed by the combination of ground parks and sky gardens. It is also the first case of Roof Park proposed (Figure 8).

Roof Park is a design concept and a design method. It can be applied to the central area of the city that also presents the absurd surface of the box-building, such as the central area of Tokyo city, Shanghai city, Chengdu city, etc., of course, the central business district of New York Manhattan, where the box-building is full of skyscrapers and high rise buildings.

5 A Concept of Greater Central Park

Central Park, New York, this completely manmade natural landscape, was designed by American landscape architects Frederick Law Olmsted and Calbert Vaux in 1858. Central Park is known as the "back garden" of New York, surrounded by 59th St., 110th St., 5th Ave., Central Park West, and 51 blocks across the North and South with 4,000 meters long, and the east and west spans 3 blocks, 800m wide and covers an area of 340ha (Figure 9). Central Park is not only a masterpiece of landscape architecture, but also a model of harmonious relationship between city and nature. It is a magical existence that points to the future from the past to the present. The Central Park 150 years ago symbolizes the future trend of urban parks.

A proposal "Greater Central Park", designed by ZHUWENYI Atelier on August 2019, explored the possibility from Manhattan Central Park to Manhattan Garden City. Based on the current Central Park, the proposal will extend eastward to 3 blocks to 2nd Avenue and 50 blocks to 6th Street to the south； create a large central park with a total area of 1,360ha, 4 times of the area than the area of Central Park (Figure 10). Rooftop Park is the main idea of the proposal. Midtown Manhattan is the prototype of the high-rise buildings in the Central Business District, the gathering place of the high-rise box-buildings. The service flat block on the east side of Central Park is also dominated by box-buildings. That is to say, in the scope of the Greater Central Park, in addition to a small number of landmark buildings, there are a large number of box-buildings that have great potential for Rooftop Urbanism, Roof Architecture, and Roof Park. There is an excellent urban governance system in New York City. The city is also a laboratory of the future city. As a design concept, proposal Greater Central Park would be one of the good interpretation of the idea of Rooftop Park and Rooftop Urbanism.

The Rooftop Urbanism proposed in this paper directly addresses the issues of contemporary urban development, urban spatial quality improvement, and urban renewal. This is the fifth in a series of articles on the theory of God's-Eye-View architecture. Rooftop Urbanism is based on God's-Eye-View first. As mentioned in the article on God's-Eye-View Architecture (I), the God's-Eye-View architecture can also be called Google Earth Architecture. By providing a satellite map from Google Earth, more issues of urban space like Rooftop Urbanism can be explored.