The Skyscraper as a Component of Public Space—The Case of Warsaw

Abstract

The following paper is devoted to the problem of relations between public space and high-rise buildings which were constructed in Warsaw in the years 1989–2022. The location of twenty-three high-rise buildings with a minimum height of one hundred meters was examined in terms of their role as basic elements of the city image and urban composition. According to the theory of K. Lynch and K. Wejchert, there were examined: multifunctionality of the space available in the public space in buildings, number of building users, parameters of the nearest neighboring public space including its area and width, and the visibility of buildings from the public space. Research shows that the high-rise buildings in Warsaw are located adjacent to public space that does not correspond to their scale and the generated traffic in the public space. Most of the analyzed buildings do not have a multifunctional ground floor, or offer more than three functions of public space. Most of the buildings are located at streets or traffic junctions while only two buildings are located at urban squares, and one at the closure of the streets. It is not possible to distinguish a coherent planning strategy related to the location of such facilities in Warsaw.

1. Introduction

1.1. Topic

The construction of a significant number of high-rise buildings is a characteristic feature of the development of Warsaw after 1990. It distinguishes Warsaw among the capitals of Central European countries after 1990 [1]. As in other European cities, the conditions for the planning of high-rise buildings in Warsaw are determined by the existing historical buildings, but the scale and momentum of their construction in Warsaw differ from those of other EU cities. This situation raises the question of the impact of high-rise buildings on the spatial structure of Warsaw. It is also necessary to examine the relationship of these buildings with the city’s public space over time.

In the first step, organizing the concepts, the types of impact of a high-rise building on the city should be categorized. For this purpose, theoretical models presented by Al-Kodmany [2,3], Lynch [4,5], and Wejchert [6] were used, as well as analysis of the influence of tall buildings on the readability and imageability of the urban environment contained in the study by Musiał [7]. The theory proposed by Al-Kodmany defines four basic factors through which high-rise buildings create the urban environment. These are imageability, human scale, socioeconomic, and spatial factors and culturally sensitive design. According to Musiał [7], tall buildings, including skyscrapers, favor the clarity and imageability of the urban environment. Their role in this respect is to act as: (1) an element of an urban composition, (2) an element of the spatial structure acting directly on the observer through its own strong form, (3) as a characteristic sign of space, and (4) as an element of the urban environment. In terms of the first three of these criteria, the structure of Warsaw was analyzed—primarily in terms of the development of the Wola district—in the works of Jóźwik [8,9,10]. Analysis concerning Warsaw is also partially included in the work of Musiał [7].

This work is devoted to research covering the fourth criterion: the impact of completed high-rise buildings on the urban environment, and more specifically on the relationships of skyscrapers and the public space closest to them. There is a lack of this type of research and studies on high-rise buildings. The existing literature on skyscrapers focuses primarily on the perception of skyscrapers as a strong form, according to K. Wejchert’s definition, affecting the city primarily visually. These studies analyze the role of high-rise buildings in creating the silhouette of the city [11]. In some of the research there is analyzed the perception of skyscrapers due to their form [12,13,14,15,16] or their role as a marker (landmark) and other elements distinguishing the components of the city’s image, both according to the theory of K. Lynch—roads, edges, regions, and nodes—as well as distinguishing elements of the urban composition given by Wejchert—dominant, borderlines and strips, roads and streets, regions, and junction points [17,18]. Researchers paid more attention to the scale, form, and silhouette of high-rise buildings and their visual impact on the urban space and perception of the city, and less on the ground floor, building base, the number of users, and their interactions with the nearest public space. Paying attention to this interaction can be seen as one of the criteria of the influence of a tall building on the city space, defined by Short [19] as permeability and connections with the public space of the base of a tall building, or in the studies of Parakh [20,21] analyzing the typology of public spaces in the vicinity of high-rise buildings.

1.2. Scope of Research

The location and surroundings of a high-rise building, combined with the design features that directly connect it to the city, are very important for the proper functioning of public spaces. High-rise buildings are facilities in which the number of users often exceeds several thousand, which makes them generators of public space activity. Therefore, they should be examined not only as graphic signs of space, present in distant—sometimes as several kilometer long perspectives and as elements of the city silhouette -on a metropolitan scale, the scale of a district or elements of an urban composition, but also on a scale the closest public space—as a living element of the city organism—permanently connected at the base with the space of the street or square.

The research covered high-rise buildings constructed in Warsaw from 1989 to 2022.

The lower boundary of high-rise buildings adopted in Polish regulations, such as the regulation “Technical conditions to be met by buildings and their location” is 55 m [22]. It is a height that does not reflect the height of 100 m above which buildings known as skyscrapers are recognized [23,24]. Among high-rise buildings, skyscrapers are characterized by: their specificity of the construction work, transferring vertical forces to the foundation and horizontal forces from high wind loads. They are buildings with a significant number of users, and due to the minimum height of 100 m, they affect large areas of the city in terms of scale and form. For this reason, a minimum height of 100 m was adopted as the criterion for the analysis of high-rise buildings in Warsaw. In the period from 1989 to 2022, a total of 23 such structures were constructed in Warsaw.

1.3. Existing Planning Context Related to High-Rise Location Strategies in Warsaw

Due to its scale and importance, a high-rise building should be the subject of careful planning. In the situation of Warsaw, in most of the analyzed period of time, there were no special regulations relating to permits for the location of such type of buildings in the city.

During the analyzed period of time in Warsaw, only a procedure for examining the impact of the designed skyscrapers on the skyline of Warsaw was developed. It is related to the protected complex of the Old Town in Warsaw, which is listed in the UNESCO World Heritage List. The procedure consists in that each planned high-rise building is assessed in terms of its impact on the view of the Old Town complex from the side of the Vistula River. Its height and silhouette was then assessed by a team of city designers. For this purpose, a 3d model of the center of Warsaw is made, with the help of which the shapes and heights of future buildings were examined.

In this way, the impact of the planned buildings (viewshed) on the views of the Old Town was assessed—i.e., a graphic image of buildings from further perspectives—about 4–5 km, which came to studying the upper parts of the buildings. However, there is no procedure for judging how a building relates to the city at its base—the relationship and interaction with public spaces was missing.

The act that regulates the procedure for granting permission to locate buildings in Poland is the Act on Spatial Planning and Development [25]. It defines spatial planning as a multi-stage procedure, which is based on two basic planning studies: “Study of the Conditions and Directions of Spatial Development” (Study) which is obligatory to do and defines the framework of the spatial policy of the entire city and “Local Spatial Development Plans” (Master Plans), which define more precisely permissible development in selected parts of the city, in accordance with the adopted Study, which is the overriding document. There is no legal obligation for the cities to make the Master Plans, which are made to be a legal local law.

The procedures for accepting both the Study and the Plan require the submission of both documents for public consultation which is collecting opinions and comments, as well as issuing opinions on both documents by specialized administrative bodies. A planning procedure constructed in this way is a two-stage procedure and includes extensive consultation with both specialists and the public, could theoretically constitute a good basis for a well-thought-out location of skyscrapers. In practice, the situation in Warsaw consists in the lack of local spatial development plans in most cases of the examined, completed high-rise buildings.

In practice, the only high-rise building from the studied, which was implemented in Warsaw on the basis of the provisions of the Master Plan, were the Warsaw Unit [26] and Generation Park [27].

The location of the remaining examined buildings was approved by carrying out the procedure envisaged in the absence of a Master Plan [25]. This procedure consist of issuing a “decision on building conditions and spatial development”, during which the actual urban planning is not carried out. The criteria which the planned building must meet in such a case are: the access of the site to a public road, the possibility of service by technical infrastructure and the fulfillment of the “good neighborhood” requirement, which consists in the compliance of functions, dimensions and intensity of development with the existing land usage in a neighboring area of the city. This area is delimited by the three-fold width of the plot on which the planned building is to be erected. When issuing a decision on the location of “building conditions”, the city office carries out an urban analysis in this area, which consists in examining what functions, dimensions and intensity of development of the area occur there. This analysis is rather an automatic urban inventory of the area and checking the compliance of the planned development with the existing buildings in the neighborhood than a real urban planning.

This simplified procedure leads to situations where:

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permits for the location of high-rise buildings are issued automatically, as long as they meet the above limited criteria of compliance with the “urban analysis” performed by the office,

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it is not possible in this “conditions of development” procedure to place a hig-rise building as a landmark, defining the urban composition (e.g., closing a street or square or emphasizing city areas and creating a network of landmarks) if there is no already built object—a skyscraper—of a similar scale nearby

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high-rise buildings in Warsaw are located in their vicinity, due to the requirement of meeting the condition of “good neighborhood” and compliance with the existing development in the area

It is worth noting here that the tallest building in the European Union at the time of writing this text—the Varso Tower office building, was built on the basis of such a simplified planning procedure.

It seems that the situation in Warsaw is currently changing, as 40% of the city’s area is covered by now by the existing Master Plans. Some of them anticipate the construction of high-rise buildings in the future. For example, the Master Plan for the most central part of the city—around the Palace of Culture and Science, where the construction of planned high-rise buildings exceeding 200 m in height [28].

A separate publication and study should be devoted to a more detailed description of conditions of the location of the planned future high-rises, permitted in the Master Plans. This text is devoted to examining the current trends in the location of the existing, already built skyscrapers in Warsaw.

Recognition the trends of planning locations of high-rises, or absence of sometrends, is particularly important when the location of skyscrapers in Warsaw was not related to planning activities consisting in urban design in the form of Master Plans. It can clearly diagnose the situation and the effects that such buildings have brought for public spaces.

1.4. The Goal of the Paper

The goal is to conduct research and to draw conclusions about the operation, location rules and features of skyscrapers in Warsaw which were built in the period of 1989–2022. The study will allow to evaluate the scale and features of this relationship and to track possible variability in time of planning and design solutions. Skyscrapers are examined not only as an element of the city panorama or as a marker which was the leading direction of research on high-rise buildings so far, e.g., [29,30,31]. The goal is above all a study of high-rise buildings as elements of the city’s image and objects connected at the base with the public space with which they remain inextricably linked. These relations of the high-rise building and the adjacent public space with the examination of the type, location and size of the public space adjacent to the high-rise building have been ignored in the research so far. Research on high-rise buildings and their relationship with public space from the point of view of passers-by focused primarily on visibility and viewshed, e.g., [18,32,33,34].

Therefore, it can be stated that the methodology that will be developed in the presented paper may be universally applicable to other locations.

2. Materials and Methods

The research methodology was to collect theoretical material on the issue, systematize the problems and define the scope of research, which was set as devoted to high-rise buildings exceeding 100 m in height, implemented in Warsaw between 1989 and 2022 and their interaction with the public space. The subject of the research is their interaction with the nearest public space—streets and squares. The next step was to define research questions, which were then categorized into three groups of analysis.

2.1. Building Functions and Traffic Generation in Public Spaces

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Analysis of the basic function of the building and the number of supplementary functions.

The research related to the answer to this question was carried out through a functional inventory of the completed buildings in the period from January to February 2022. A building with at least three functions supplementing the basic function was treated as a multi-functional building in the part of the ground floor adjacent to the public space. As supplementary functions that can be used, the following can be distinguished: commercial (H), gastronomic (G), service (U)—e.g., financial, tourism, legal, insurance services, etc., medical (M)—e.g., a health facility, pharmacy, etc., sports (S)—e.g., fitness, wellness (W)—e.g., beauty salons, hairdresser, massage, etc., entertainment (R)—e.g., clubs, viewing terraces, etc., educational (O)—e.g., nursery, kindergarten, etc.

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Analysis of the pedestrian traffic generated by the building in the public space.

Research on this and the next criterion was carried out by collecting data from specialist studies, interviews with designers and building administrators. To estimate the number of users, 7 m² of GLA space per 1 user of offices was assumed [35], and an average of 3 people per apartment or 25 m² of PUM per person. These values are an indicator—e.g., the number of office users indicates the estimated potential maximum number of employees that can simultaneously work in these buildings, not taking into account absenteeism, the vacancy rate or the possibility of arranging an office space which is lower than the maximum density of employees.

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Analysis of the number of users using public transport.

To estimate the indicator of people using public transport, it was assumed that for buildings with a basic office function, one user arrives with one car. Other estimated users of the building are assumed to use public transport or bicycles as long as the building offers parking spaces for bicycles. For buildings with a basic residential function, an indicator was adopted that one person living in a flat uses a car and half of the remaining people use public transport.

2.2. Interaction with the Nearest Adjacent Public Space

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Analysis of the type of the nearest neighboring public space.

The research was carried out based on spatial and functional inventories.

The closest adjacent public space was considered to be the space adjacent to the main entrance to the building and limited by the road system in front of the building. The basic types of public space are: street (UL), square (PL), square (SK), intersection (KR), space dedicated to public transport or a transport junction (TR). The study was considered important due to the determination of the trend in the location of high-rise buildings in Warsaw.

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Analysis of the area of the nearest neighboring public space.

The study of this and the next criterion was carried out based on collected maps from municipal resources as well as municipal and state geodetic services. The area of the public space between the lines of the facades in the building with entrances and the curb of the road system closest to them was measured.

Following the studies by Parakh [20,21] analyzing open spaces next to high-rise buildings, the following types of space were distinguished: small space (up to 1000 m²), medium (from 1000 m² to 4000 m²), large (from 4000 m²), very large and significant for the city (from 80,000 m²).

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Analysis of the width of the public space adjacent to the building.

The width of the widest public space (e.g., street or square) at which the building is located was measured, along its boundaries. This study is important due to the analysis of the spatial policy related to the location of high-rise buildings in Warsaw and the determination of the proportion of public space located in the vicinity of the building: its width to the height of the building under study. These proportions influence the perception of the building being examined by passers-by.

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Permeability through plot analysis.

The research was based on on-site visits and assessment of existing buildings and maps from municipal and state surveying resources. The levels of permeability through the plot on which the building was erected were assessed. Permeability grades have been defined as non-permeable (BP), partial permeability (CP), which occurs when part of the plot is left as a defined public space, without the possibility of passing the plot, two-, three-, four-sided permeability (2P, 3P, 4P), depending on the number of directions from which a pedestrian can cross the plot between public spaces.

2.3. Perception of the Building from the Public Space

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Analysis of the importance of the location of the building for the image of the city and urban composition.

The research on this and the other two criteria was carried out based on on-site visits and urban inventory. The following were assessed: terminating the view of the streets (DU) by the building, marking the course of linear elements of the city—streets or edges (PU), marking the node (W) or corner of the quarter geometry (WK). These criteria may be present simultaneously.

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Building form analysis.

It is a criterion that allows examining the design and planning strategy for placing buildings in the historic buildings of central Warsaw. As part of this criterion, one can distinguish the examination of the feature that the building has a separate part of the podium. As part of this feature, in turn, it is possible to examine the reference of part of the podium to the height of the surrounding buildings and the property of the building form consisting in the location of the main tower block of the building as located in the border delineating the public space of the city. These are the features of the form of high-rise buildings, which make the body of the high-rise building create relationships with historical buildings, a characteristic frontage of public space, or a characteristic marker.

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Analysis of the visibility of the full form of the building from the public space.

The adequate visibility of the full form of the object from the public space was considered to be the possibility of viewing the entire building from the level of the public space at the angle of visibility that is comfortable for passers-by—i.e., 53 degrees. It was found that it is not important from what distance such visibility is ensured, provided that it takes place at the angle of visibility of pedestrians and from the public space. The ability to conveniently observe the entire mass of the building from public space, not obscured by other buildings, was considered a feature indicating that the mass may play a role in building a map of landmarks [4] related to the shaping of the city’s image by the user. It is assumed that high-rise objects visible in this way from the public space can fulfill their full potential of creating a landmark.

3. Results

The results of the research are presented in tabular form. The location of analyzed building is shown on Figure 1.

Table 1. Research in terms of function criteria and traffic generation in public space. Legend: 1—Year of construction. 2—Total height (m). 3—Number of overground storeys. 4—Basic function: office (B), residential (M), hotel (H). 5—Ground floor multi-functionality: commercial (H), gastronomic (G), service (U), medical (M), sports (S), wellness (W), entertainment (R), educational (O). 6—Total overground gross area (m²). 7—Estimated number of users. 8—Number of parking spaces for cars. 9—Number of parking spaces for bicycles; 10—Index of users using public transport (%).

No.	Name:	1 Year of Construction	2 Total Height	3 Number of Overground Storeys	4 Basic Function	5 Ground Floor Multi-Functionality	6 Total Overground Gross Area	7 Number of Users	8 Number of Parking Spaces for Cars	9 Number of Parking Spaces for Bicycles	10 Index of Users Using Public Transport
1	Varso Tower	2022	310	54	B	G, R (1)	86,000	10,000	116	250	98.8%
2	Warsaw Spire	2016	220	49	B	G, S, O, U	74,000	8500	766	379	90.8%
3	Warsaw Trade Tower	1999	208	43	B	H, G, S, O, W	54,800	6000	450	100	92%
4	Warsaw Unit	2021	202	46	B	G	72,800	8200	456	310	94%
5	Skyliner	2021	195	45	B	H, G, U, R	72,000	7000	430	300	93.8%
6	Q22	2016	195	42	B	G, H, S,	69,000	7500	348	110	95.4%
7	Złota 44	2013	192	55	M	U, G	72,500	712	288	0	29%
8	Rondo 1	2006	192	40	B	H, S, G, O, U+	103,000	9500	490	120	95%
9	Generation Park	2021	180	40	B	G	61,800	6800	325	187	95.2%
10	Cetrum LIM	1989	170	43	H, B	U, H, G, M, R+	87,600	1046 (H) 1700 (B)	248	0	85%
11	Warsaw Financial Center	1998	165	32	B	G, H, U	81,300	7100	350	0	95%
12	Inter Continental	2004	164	45	H	-	57,000	828	175	0	58%
13	Cosmopolitan	2013	160	44	M	G, U	60,939	630	300	0	26%
14	Mennica Legacy Tower	2020	141	32	B	S, G, U	50,700	7050	608	300	92%
15	The Warsaw Hub	2020	130	31	B	G, H, U, S+	98,000	10,700	1000	286	90%
16	Spektrum	2003	128	35	B	G, R	49,900	5800	314	110	94.5%
17	Łucka City	2004	120	30	M	H, U, R	51,000	855	350	-	29.5%
18	Błękitny Wieżowiec	1991	120	27	B	H, G, U+	37,500	3350	39	-	98.8%
19	Atlas Tower	1999	116	28	B	S, G, H, U+	52,900	4030	539	-	86.6%
20	Central Tower	1996	115	26	B	G, H	14,400	1650	-	-	100%
21	Złote Tarasy–Skylight	2007	105	26	B	G, H	23,000	2780	770	130	72.3%
22	Babka Tower	2000	105	28	M/B	G, H, U	84,850	2600	675	-	74%
23	Ilmet	1997	103	22	B	-	32,500	2350	212	-	91%

⁽¹⁾—the entirety of the Varso Place team consists of the Varso 1, Varso 2 and Varso Tower buildings connected on the ground floor, which in total offer more functions available from public spaces: H, G, U, W, M, R.

presents studies in terms of the criteria of functions and traffic generation in public space, in

Table 2. Research in terms of the criteria of interaction with the closest public space and the perception of the building from the public space. Legend: 1—Type of adjacent public space: street (UL), square (PL), square (SK), intersection (KR), space dedicated to transport, transport node (TR). 2—The width of the adjacent widest street/square in the demarcation lines at which the building is located (m). 3—Area of public space directly adjacent to the building (m²), small space, up to 1000 m² (M), medium—from 1000 m² to 4000 m² (S), large—from 4000 m² (D), very large and significant at the same time for the city—from 80,000 m² (BD). 4—Permeability of the site: no permeability (BP), partial permeability (CP), two-, three-, four-way permeability (2P, 3P, 4P). 5—Locations in the urban context: terminating the view of streets (DU), determining the course of linear elements of the city–streets or edges (PU), determining the node (W), corner of the quarter geometry (WK). 6—Building form: tower (W), tower with a podium (WP), tower with a podium adapted to the neighboring buildings (Pd), tower located on the border of public space (Wp). 7—Visibility from public space: it is possible to see the whole building from the spatial level (V1), not possible (V0).

No.	Name:	1 Type of Adjacent Public Space	2 The Width of the Widest Adjacent Street	3 Area of Public Space Directly Adjacent to the Building	4 Permeability of the Site	5 Locations in the Urban Context	6 Building Form	7 Visibility from Public Space
1	Varso Place	UL, TR	54	970, M	4P	WK	Wp	V0
2	Warsaw Spire	PL, UL	87	7500, D	2P	PU, WK	Wp	V1
3	Warsaw Trade Tower	UL	59	8330, D	3P	PU, WK	WpPd	V1
4	Warsaw Unit	TR	64	990, M	BP	W, PU	Wp	V1
5	Skyliner	UL	87	760, M	BP	PU	Wp	V1
6	Q22	UL	62	2400, S	BP	PU, WK	WpPd	V1
7	Złota 44	UL	27	970, M	BP	PU	WpPd	V0
8	Rondo 1	TR	73	1500, S	2P	WK, PU, W	WpP	V1
9	Generation Park	TR	50	2500, S	3P	WK, PU, W	Wp	V1
10	Cetrum LIM	UL	62	4800, D	2P	WK	WP	V1
11	Warsaw Financial Center	UL, S	57	1220, S	BP	WK	Wp	V1
12	Inter Continental	UL	57	1400, S	BP	PU	WpP	V1
13	Cosmopolitan	UL	34	990, M	2P	DU	WP	V1
14	Mennica Legacy Tower	UL	53	5500, S	2P	PU	W	V1
15	The Warsaw Hub (dwie wieże)	UL, TR	64	6400, D	2P	PU	W	V1
16	Spektrum	UL	18	370, M	BP	PU	WPd	V0
17	Łucka City	UL	18	250, M	BP	PU	WP	V0
18	Błękitny Wieżowiec	PL	70	2000, S	2P	W, WK	WPd	V1
19	Atlas Tower	UL	66	920, M	BP	W	WPd	V1
20	Central Tower	TR, UL	80	850, M	BP	WK	Wp	V0
21	Złote Tarasy–Skylight	UL	57	780, M	BP	PU	WP	V1
22	Babka Tower	TR	55	4500, D	BP	W	WpPd	V1
23	Ilmet	TR, S	73	3600, S	BP	WK	WpPd	V1

studies in terms of the criteria of interaction with the nearest public space and the perception of a building from the public space.

3.1. The Results of Research on the Function of the Building and the Generation of Traffic in Public Space

In the majority of—74% of the surveyed buildings, the primary function is offices, for 17% of buildings it is the residential, and for 9%—as a hotel. The visible advantage of the office function results in generating a lot of traffic in public space by these buildings: the total estimated potential number of users of the office function of the examined buildings is 102,510 people, which is comparable to a large county city in Poland. From the group of buildings with office functions, the Varso tower has the most potential users—about 10,000 people (which will double this value after adding the lower office buildings of the complex), and the least—Central Tower—about 1650. Two buildings—Centrum Lim and Babka Tower are very beneficial for the operation of public space, doubling the basic function—in the first case they are offices and a hotel and in the second—offices and apartments. This gives the building the effect of operating a greater time range during the day and increases the number of necessary main connections to public space.

In terms of the multi-functionality of the basement part of the building, 34% of buildings did not offer multi-functionality understood as the availability of 3 or more functions for users of public space. At the other extreme, there are skyscrapers with a rich functional program of the podium part, accessible from the ground floor of the building, such as the Rondo 1 complex, Centrum Lim, The Warsaw Hub, and Atlas Tower. In two of them—Centrum Lim and Atlas Tower, these are commercial and service parts organized in the form of a gallery.

Office towers are built with the assumption that the majority—from 85% to 100% of potential users will commute to them by public transport, despite the implemented parking parts located below the ground floor, up to 5 floors (Warsaw Spire) and 1000 parking spaces (The Warsaw Hub).

3.2. The Results of Research on the Interaction of Buildings with the Nearest Adjacent Public Space

Most—52% of buildings are constructed as planned on the street, 34% as located next to transport spaces—roundabouts, flyovers, 8.6% as located next to transport spaces—roundabouts and adjacent to the square at the same time, only 5.4%, i.e., 2 buildings—Błękity Wieżowiec and Warsaw Spire are planned at city squares. The buildings were planned on streets with an average width of 58 m along the dividing lines, although two of them—Spektrum and Łucka City were built on narrow streets—only 18 m wide.

In the largest number—43%, the public space directly adjacent to the building is small—up to 1000 m², with the smallest values in front of the Łucka City building—250 m² and Spektrum—370 m². 35% of the buildings are directly adjacent to a medium-sized public space, and 22% to a large public space, the largest of which has over 8000 m² and is located in front of the Warsaw Trade Tower.

There are no buildings near a large and significant public space for the city.

Most of the buildings—53.5% do not provide passage through the area in which they are built, the rest of the majority provide a one-way passage through the area, and three—more than one-way—are Varso Tower Complex (Figure 2), Warsaw Trade Tower, and Generation Park Complex.

3.3. The Results of Research on the Perception of the Building from the Public Space

In terms of creating the image of the city and the urban composition, 65% of the buildings are marked by street spaces, 17% of which are also the corner of the quarter, and two—Rondo 1 and Generation Park, due to their corner location, are also corner markers associated with junctions and nodes. 21.7% of the buildings constitute the node, and one building—Cosmopolitan (Figure 3) is planned as clearly closing the street—Emilii Plater.

Most of the buildings—60.8% are built in the form of a tower with a podium, half of which in such a way that the tower part is located on the border of the public space—the line separating the streets. 39.2% of the buildings are towers without a part of the podium, of which only two—Mennica Legacy Tower and The Warsaw Hub—are towers not directly touching the street border.

Due to the location on wide streets, it is possible to see the entire body of most buildings from a further perspective from the angle of view of passers-by. This is not possible for five of them, including the highest one—Varso Tower: located on the wide Aleja Jana Pawła II, but blocked by a road flyover running opposite it. A similar case is the Central Tower, located at the same communication flyover, on the opposite, southern side of Al. Jerozolimskie. The others are Złota 44, Łucka City, and Spectrum, located on narrow or very narrow streets.

4. Discussion

4.1. The Problem of the Size of the Public Spaces Adjacent to the Buildings

As far as locating Warsaw high-rise buildings, it is evident that the issue of the appropriate size of public space directly adjacent to the building is overlooked, even though the vast majority of buildings are intended for the basic office function characterized by a high density of employees, which, combined with the scale of the buildings, generates large numbers of users of the buildings under study. Most of the facilities are planned with a small space of this type, in extreme cases—Spektrum and Złota 44 facilities not exceeding 370 m². This is particularly unfavorable for the Spektrum building, which, due to its basic office function, is intended for a larger number of users, up to 5800, than the Złota 44 residential tower. This situation leads to excessive crowding of public space during morning and afternoon traffic peaks—it is inconvenient both for building users and city users. A similar situation occurs in the case of Varso Tower, which—although designed as the tallest building in the European Union, intended for approximately 10,000 users, is planned with a small public space of approximately 970 m. In his case, large-sized internal open spaces, shaped as a common passage connecting the Varso Tower with the other two buildings of the Varso complex, can help to fill the building and unload the congestion.

The fact that, although buildings are mostly located on statistically wide streets, the number of public spaces adjacent to them is small, indicates that planning decisions are rather issued without taking into account the need to locate such facilities with the corresponding amount of public space, and investors are reluctant to allocate the area to public spaces or public (except for Warsaw Spire, where a large public space of Plac Europejski square has been developed within the investor’s area, which is shown on Figure 4).

4.2. Permeability and Multi-Functionality of Buildings

The inability to cross the investor’s site in the case of the implementation of over 56% of buildings proves the lack of interest of investors, planners, and city decision-makers in stronger interactions of the built objects with public space, although research shows that this trend is slowly reversing. Buildings without the possibility of crossing a plot of land are on average sixteen years old, buildings with the possibility of going in more than one direction—twelve, and the newest and highest—Varso team will offer the possibility of going in four directions through the complex.

As part of the building’s interaction with the public space, in most cases, the parts of the buildings that connect to the site are multifunctional. Four of them offer a range of public space functions, organized in the form of arcades or commercial and service clusters. These are Centrum Lim, Warsaw Trade Tower, Atlas Tower, and Rondo 1. A similar solution, considering more broadly the connections of the analyzed skyscrapers with other buildings belonging to the same development complexes, is offered by The Warsaw Hub and Varso Tower.

It is characteristic that the largest of the multi-functional parts of the surveyed buildings, located in Centrum Lim, Atlas Tower, and Warsaw Trade Tower, were completed the earliest—more than twenty years ago. At the same time, in most of these cases, the immediately adjacent public space was large.

The high multi-functionality of, above all, older skyscrapers proves that investors are withdrawing over time from the strategy of implementing high-rise buildings with a highly multifunctional ground floor during the period under study, and a question can be asked whether the latest buildings such as The Warsaw Hub from 2020, Skyliner from 2021 or the currently completed team Varso having multifunctional ground floors are a signal of more permanent changes in this trend.

4.3. Problems of Generating Pedestrian Traffic

A feature of older skyscrapers is greater reliance on individual cars than on public transport compared to the latest implementations. The newest—Varso Tower, with one of the largest numbers of users—around 10,000 people (excluding the other two buildings in the complex), has only 116 parking spaces for cars: an estimated 99% of employees use city public transport or bicycles. In this case, it can be said that planning such a functioning facility generating a lot of pedestrian and bicycle traffic in a small public space is disadvantageous for its operation.

4.4. The Problem of the Image of the City and the Perception of Buildings from Public Space

From the point of view of the image of the city and the urban composition, it is significant that the location of most of the buildings means that they primarily determine the course of the street and, to the least extent, can be perceived as marking clear view closures (which is only a feature of the Cosmopolitan building) or the spaces of squares (which characterizes two of them: the Blue Tower (Figure 5) and the Warsaw Spire, of which only the first one is located at a square recognizable by Warsaw residents, existing before the construction of the building).

Although a large group of objects: six—are located in such a way that they mark nodes, 66% of objects in this group constitute a communication node, which is not a strong element of the actively used public space system. The situation of this insufficient realization between the rank and scale of the building and its location in terms of the urban composition is improved by the fact that almost half—47.8% of the buildings constitute the dominant feature located at the corner of the streets, delimiting the quarters of buildings in which they are implemented.

In terms of the perception of objects from the public space, the vast majority of objects are buildings with a separate part of the podium and a tower. This feature is characteristic of older buildings, it always occurs in the projects from 1999 to 2013. The newest buildings from 2020–2022 are buildings in the form of towers without a podium and it can be observed whether this formal change will be maintained in the coming years. The distinctive feature of the facilities implemented in Warsaw in formal terms is that regardless of whether the facilities are erected as having a podium or not, most often—in 60% of cases, the tower part of the facility is located on the border of the public space or the border of street boundaries, in direct contact with the ground. This is probably the result of the implementation of objects on plots of land that are small concerning the scale, but the perception of the tower from the public space is clear.

The visibility of the vast majority of objects from the level of the user of public space is ensured by wide communication arteries planned in Warsaw after the war (although four of the examined buildings are impossible to see from the public space as a whole), which means that these buildings can be permanently embedded as elements of the city’s image by city’s inhabitants.

4.5. Strategies for the Location of Skyscrapers in Other European Countries in Relation to the Relationship with Public Space

The tradition of building skyscrapers in Western European cities is much longer than in Warsaw. European experience of the implementation of this type of buildings rely on careful and thoughtful location of both clusters and individual skyscrapers. In the analyzed period—1989–2022, the characteristic scale for the objects raised in the European Union and Great Britain was the height, which was slightly more than 200 m [23]. There is also a tendency to erect more and more buildings over 150 m high and, in recent years, over 200 m [7].

There are noticeable two parallel trends:

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planning of zones for high-rise buildings or deglomeration of high-rise buildings outside the city center, examples of which are Canary Wharf in London, La Defense in Paris, Donau City in Vienna, Zuidas in Amsterdam, Centro Direzionale in Naples, Plaza d’Europa in Barcelona and European Union Moscow City,

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central location, reconstruction of an existing urban structure and creation of groups of skyscrapers or landmarks, as exemplified by the City of London, Frankfurt am Main, Milan, Berlin to some extent Madrid and Cologne.

The issue of the location of a skyscraper in relation to the historic structure of the city is often the subject of long discussions and analyzes in Europe. Various studies and analyzes of views and panoramas are carried out in order to determine the places where skyscrapers cannot be located. For example, in London, where many skyscrapers are built, one of the criteria determining their location is the lack of collisions with the designated viewing corridors.

In Western Europe, there is also a noticeable tendency to consciously plan high-rise buildings not only as an element of the city skyline, but also as an element constituting a component of public space. This is the case not only of designating zones and districts for high-rise buildings—such as La Defense in Paris, Canary Wharf in London or Donau City or development along Paseo de la Castellana in Madrid, but also in the planning and implementation of free-standing high-rises. Examples of the latter are skyscrapers in Frankfurt am Main, e.g., Commerzbank erected adjacent to important public spaces, Koln Turn in Cologne erected by the square, Porta Nuova Garibaldi and Palazzo Lombardia in Milan, erected together with squares located directly next to the buildings, Generali Tower in Milan located with the square, and planned skyscrapers in the City of London like 1 Udershaft and Heron Plaza, where a carefully planned public space is to be built.

The situation related to the planning and construction of high-rise buildings in European Union cities is therefore more mature and subject to planning considerations than in the case of the projects realized so far in Warsaw, where the location of skyscrapers at squares—existing or planned—is an exception.

4.6. Conclusions Regarding the Existing Strategy of the Implementation of High-Rise Buildings in Warsaw

Certainly, the completed Warsaw skyscrapers, from the point of view of the urban composition, do not constitute integral parts of planning visions or evidence of a clear spatial policy regarding this type of buildings. They are also not elements strengthening the network of public spaces of the city and crystallizing their spatial arrangement. Despite the fact that they are implemented with respect to the skyline composition and the role they play in the city panorama, their location is inadequate in relation to the system of adjacent public spaces. Certainly, high-rise buildings should be planned so that they constitute an important complement to nodes, edges and paths in the structure of the city image. The studies prove that in the case of Warsaw there is a poor integration of these buildings with the immediate surroundings. In the future, high-rise buildings in Warsaw should be planned, taking into account the implementation of their ground floor as a multifunctional and permeable, planned with with a clearly defined public space of medium or larger size located in their immediate vicinity.

The current practice of issuing consents for the location of high-rise buildings in Warsaw consisted in spontaneous presentation of plans for the construction of this type of buildings by developers and the launch of a simplified procedure for issuing a planning decision—“development conditions”—by the city. The procedure for issuing this decision was to a large extent automatic, and the only analytical procedure for assessing the impact of these buildings on the city was the procedure for the viewshed of these buildings on the city skyline visible from the eastern side—the Vistula River. This was to preserve the view of the old town in Warsaw, the complex of which is ilisted on the UNESCO World Heritage List [36,37]. It is a procedure assessing the influence of building visibility on the skyline, not its relation to the public space. The procedure for issuing decisions on “development conditions” in Warsaw is based on the principle of “good neighborhood” for decisions issued (described earlier). As a result of the necessity to meet such a criterion, most of the skyscrapers in Warsaw are grouped next to each other, in the central area of the city. It is certainly beneficial for the view of the skyline of Warsaw as it has led to the construction of buildings in one central area of the metropolis. Unfortunately, permission for the location of these buildings was issued without examining the impact and relationship of these buildings with the public space of streets, squares and nodes.

It is difficult then to assign their location to any model of high-rise building location mentioned by the literature: the European, American, or Middle Eastern model mentioned by Paszkowski [17] or a similar one indicated in the publications of Jasiński [38].

The American model is to build high-rise buildings adjacent to each other, and the various ways of locating such buildings in Europe which was presented earlier in the paper can be summed up in such a way that they often constitute a component of the implementation of larger urban assumptions, or visions regarding the principles of their introduction into urban spaces [39]

In Warsaw, after the research has been carried out, it can be concluded that it is impossible to distinguish any of these methods as urban markers. It can be concluded that the location of Warsaw high-rise buildings and their relations with public space is the result of leaving the construction of this type of buildings primarily to the market forces and the possibilities or ambitions of developers as well as general building regulations. The location of the buildings was spontaneous, partially governed by simplified rules for issuing a location decision regarding “development conditions”. The research shows the superficiality and temporary nature of the spatial policy with regard to the location of high-rise buildings.

The results of the research in terms of spatial policy show that decisions are made primarily in terms of spatial results, economic considerations and prestige. In the analyzed period, there is an intense, speculative expansion of capital aimed at achieving the highest possible profits [40].

The image of the city in terms of the location of high-rise buildings presents the results as an effect of globalization activities. High-rise buildings are signs of revitalized spaces and development. It can be said here that Warsaw is a city undergoing a strong transformation and its mechanisms were primarily regulated by the market and the economy. As a result, the genesis of most Warsaw skyscrapers is partially analogous to the construction of American skyscrapers, which are an expression of the city’s vitality, economic energy, market power, ambitions, and technical possibilities rather than strict urban planning in the contemporary European sense.

The situation of a real lack of planning related to the location of high-rise buildings results in not using their full city-forming potential, and incoherent urban tissue.

Certainly, the situation will be improved by departing from the current strategy, consisting mainly in planning activities related to the procedure of issuing decisions on “development conditions” for the implementation according to local Master Plans. The aforementioned procedure for the preparation of “development conditions” is a simplified procedure, ad-hoc issuance of decisions on the construction of high-rise buildings, which simplifies the planning process. It is based primarily on the city’s operation as a passive body that checks the applications prepared by developers, and not as an active entity planning the construction of high-rise buildings according to its assumptions, plans and policies. Therefore, it is worth preparing a set of analyzes and criteria for planning the location of high-rise buildings as part of spatial planning, the effect of which is a local plan.

In terms of the relationship between the planned high-rise buildings and the public space, the research shows the necessity to conduct the following analyzes as part of planning procedures at the stage of preparing a local Master Plan.

• Analysis of the urban context
  • Analysis of the topography and the unique form of the surrounding landscape
  • Analysis of the layout of the surrounding public spaces
  • Analysis of the scale of the surrounding buildings
• Analysis of the impact of buildings on transport conditions
  • Analysis of the potential users of the building
  • Analysis of the necessary parking spaces for cars and bicycles
  • Analysis of pedestrian traffic generated by buildings
  • Analysis of ensuring adequate transport capacity: roads, bicycle paths and public transport
• Analysis of the building’s role in the functioning of public spaces
  • Analysis of the functionality of the ground floor of the building
  • Analysis of the permeability of the site
  • Analysis of the improvement in the perception of the area in the near and further context
• Analysis of the building’s operation in the context of building the city’s image
  • Analysis of the building’s visibility from the public space
  • Analysis of the building’s operation as an element crystallizing the structure of public networks in a city: building as an element defining path, edgeges, regions or nodes
  • Analysis of the possibility of creating a defined public space around the building: medium or large

5. Conclusions

The paper presented research which was devoted to the relations between high-rise buildings built in Warsaw in the years 1908–2022 and the surrounding public space. The selected scopes of research were:

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building functions and generating traffic in public space: the basic and supplementary functions of the building, the scale of pedestrian traffic generated by building users, the degree of use of public transport were examined,

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perception of the building from the public space: the significance of the building for the image of the city and urban composition was examined, the form of the building in terms of its proximity to the public space, visibility of the entire form of the building from the building space.

The conducted research makes a new contribution to the research issues of buildings implemented in metropolitan areas, because the scope of the study is focused primarily on the operation of buildings within public spaces—streets and squares. They focus on the contact between buildings and the public space and interaction with it, and not—as most of the research conducted so far—on the influence of buildings on the visibility (viewshed) of the metropolis and on its skyline in a broader sense.

The paper presents the results of the research together with conclusions and postulates to be introduced in future planning works carried out by the city, related to allowing the location of high-rise buildings in terms of creating a correct public space in their surroundings.

On the scale of Warsaw, the location of high-rise buildings coincides with the area delimiting the center, which makes its central part visible in the distant perspective of the city skyline. However, the research shows that on a local scale and in terms of the connection of skyscrapers with public space, the location in some cases was not subordinated to a coherent, separable planning policy, and the public space adjacent to the building is modest in size and does not correspond to the rank and scale of the high-rise building located.

Most of the completed buildings do not have a multi-functional part of the groundfloor which would be beneficial for the operation of public spaces. In the completed buildings there is a problem with permeability.

Some buildings, such do not co-create a coherent development with the neighboring buildings, and in the case of a podium facility, almost 60% of such buildings have a podium scale that does not correspond to the neighboring buildings and public space.

Comparing the constructed Warsaw skyscrapers with the European experience related to the construction of such buildings, it can be stated that it is crucial to connect landmarks with important public spaces—existing or planned and generally accessible buildings with vital, center-forming functions, gathering large numbers of users.

Certainly, a high-rise building can be planned and designed in such a way that for the city it is something more than an icon visible in the panorama—that is, an important and logical component of public space, having a well-functioning, multifunctional space accessible from public space, visible intrusion and exhibition in city landscape, which will consist of medium or large public space next to which it is being implemented.

It is worth making future planning decisions in Warsaw to try to achieve such goals.

For this reason, the paper indicates the postulated analyzes useful in the future planning of high-rise buildings as part of the preparation of future local Master Plans.