In the book How Buildings Learn, Stewart Brand adopts an architectural framework that was proposed by Frank Duffy in 1990. Duffy’s framework introduces a time-based understanding of buildings. He distinguishes between the shell, services and scenery of a building, with each having its own time frame before being replaced or adapted.14 Brand subsequently acknowledges that Duffy was one of few theorists of change rate in buildings at the time his book was published in 1994. To adapt Duffy’s framework for more general use, Brand renames the layers proposed by Duffy and adds additional layers.15 The resulting framework contains six typological levels which are referred to as ‘shearing layers‘. According to Brand, a building is constantly tearing itself apart due to the difference in longevity of these various layers. As Table 1 shows, these layers include site, structure, skin, services, space plan and personal stuff.

In terms of the physical scope, Brand’s framework provides a holistic overview of the architectural environment from a physical point of view. Interestingly personal stuff is included as the smallest and most rapidly changing layer. Here, Brand implies that the creation of an environment is not limited to the architectural fabric. Rather, the process includes the intervening impact of the users or residents themselves, usually through the arrangement of furniture and other objects. At the other end of the scale, the largest shearing layer is the site. The scope of the framework, therefore, includes the building itself and the spaces found directly around it. Brand emphasises the interrelation between the typological categories, meaning that the larger layers play a determining role for the smaller layers.16 For example, the structural grid (structure) of the building determines the possibilities for the interior division made by non-load-bearing walls (space plan). At the same time, based on the positioning of these non-load-bearing walls, the layout of the rooms (space plan) partly dictates the placement of furniture (personal stuff).

In terms of a communication tool, the terminology used in Brand’s framework to describe the environment is easily understandable and sufficiently precise. Shearing layers should therefore be understandable by researchers both with or without a background in spatial disciplines.

In terms of a research tool, the framework is primarily aimed at understanding the evolution of buildings through time. Nevertheless, abstracting a building into these categories also opens up ways of understanding how a building interacts with different categories of users. We can draw a parallel between the size of a shearing layer and the size of the social constellations they influence. While personal stuff is closely related to individuals, as the scale of a layer increases, so does the scale of social constellations with which they interact.17 Personal stuff interacts with individual residents and space plans with residents’ groups as a whole, and the skin of the building is in dialogue with the general public, consisting (from the residents‘ point of view) mostly of unknown individuals. Therefore, the shearing layers contain the potential for being used as a theoretical framework guiding empirical research.

Housing Design: A manual is a handbook aimed at supporting the practice of designing housing.18 Bernard Leupen and Harald Mooij have a background in architectural research, with a focus on design methodology. Their book concentrates mainly on collective housing as opposed to individual housing. This not only fits in with Dutch housing culture, but also responds to a more general need for housing densification, one of the critical urban challenges of modern times. The chapters of this book are organised around typological elements of the residential environment which is a combination of the framework introduced by Argan in 196419 and that introduced by Stewart Brand in 1994 (see above). The authors combine and adapt Argan’s and Brand’s frameworks according to the specific complexity of residential buildings, resulting in the framework presented in Table 2. The typological categories are arranged by scale from large to small. They range from the context, representing broad elements that influence housing designs, to tectonics, representing the material properties of the dwelling.

In terms of the physical scope, Housing Design: A manual offers an extensive overview of the typological elements of the residential environment. This environment is not merely the result of architectural design but exists within a larger context of both tangible and intangible influences. These are included as context. On the other side of the spectrum, we can find the smallest elements of the residential environment – tectonics – which is based on the reframing of the shearing layers of Brand. Tectonics in this case refers to the material composition of architectural elements of buildings.

In terms of a communication tool, the categories of the environment are organised in a two-level hierarchy. In doing so, the authors can strike a balance between complexity and understandability. However, while the terminology might be intuitive for designers, it could be complicated for researchers without a background in spatial disciplines.

In terms of a research tool, the framework is conceptualised to be broadly applicable by architectural and urban designers. Therefore, it does not actively seek to make theoretical links with social science disciplines. However, the clear distinction between typological elements and their organisation into a hierarchical structure opens up the potential for the framework to serve as a tool for researchers interested in studying the socio-spatial environment.

A Pattern Language by Christopher Alexander et al. is the result of the authors’ typological understanding of the physical environment. The language emerges out of interconnected patterns, which can be seen as problems that regularly occur in our environment.20 An overview of all patterns is given in the introductory section of the book; referred to as a summary of the language, it organises the 253 patterns into 36 groups. Each of these 36 groups contains between four and 10 individual patterns, as shown in Table 3.

In terms of its physical scope, A Pattern Language presents a holistic understanding of the physical environment while remaining systematic. It follows the principle that all patterns are organised from large to small. The large number of patterns illustrates the continuous nature of the physical environment and emphasises how smaller-scale environments are always embedded within a larger-scale context. Although the book does not focus specifically on the residential environment, explicit attention is given to housing and dwellings in several sections of the book. Furthermore, A Pattern Language offers insight into larger-scale levels of the socio-physical environment, while the smallest pattern confirms the importance of personal stuff as part of the physical environment, in line with Brand’s shearing layers.

In terms of being a communication tool, attention has been given to using understandable terminology. The book is not just aimed at architects, it could also be used as a tool for auto-construction. The authors explicitly encourage readers to adapt the pattern language presented in the book to create their own pattern language. Therefore, the terminology should be understandable by researchers without a background in architecture.

In terms of being a research tool, while the 253 patterns present a holistic understanding of the physical environment, the large number of patterns makes it difficult to directly translate the framework into a research tool. Therefore, to fit this goal, the 253 patterns would need to be simplified into fewer categories. Furthermore, each pattern is elaborated in a concise format that describes the empirical background and the physical and social context of the pattern. The framework makes explicit references to knowledge from social science disciplines.

Assessing these frameworks, shearing layers offer a clear and understandable typology of building components; Brand’s focus is on detailing the elements that compose buildings, with larger aspects that go beyond the building playing a secondary role. The typological framework found in Housing Design: A manual then combines shearing layers with another framework by Argan. In doing so, the authors elaborate the scope of shearing layers into a more expansive framework for understanding the residential environment where more large-scale elements are added. This goes beyond the scope of the building in the form of urban ensembles or building blocks and contextual elements. In relation to these, A Pattern Language offers the most extensive examination of the residential environment. The large number of patterns emphasises the continuous nature and interconnectedness of the different elements of the physical environment on different scales. Additionally, it explicitly seeks to connect spatial aspects of the residential environment with its social aspects by providing empirical evidence in the description of the patterns.

These three frameworks can be combined to derive a possible new group of categories of the residential environment. Figure 1 shows the constituent elements of each framework, which are then systematically interpreted against one of three positions. Each element is judged to be directly relevant and included in our proposed framework (as shown with a line), considered as an influence (as shown with a single asterisk) or considered to fall outside the residential sphere (as shown with a double asterisk) and therefore is not included in the proposed framework.

As a result, five distinct categories emerge that can be considered typological categories of the residential environment: life-environment, neighbourhood, dwelling, tectonics and personal stuff. By basing these categories on existing architectural frameworks, we ensure that they are rooted in existing knowledge of architectural typology. It is important to take this newly developed framework of typological categories and measure it against the same criteria used to evaluate the previous frameworks.

In terms of physical scope, the overlap of the three frameworks endows the new one with broad, holistic coverage of the residential environment. The dwelling can be found at the core of the new typological framework with two smaller categories – tectonics and personal stuff – and two larger categories – neighbourhood and life-environment. Nevertheless, there are some elements that do not fall exactly into one of the five derived categories. These include abstract processes that influence housing in indirect ways and are difficult to associate with a specific architectural scope, and are considered to be influences. We note that ‘technology’, which can be traced in the evaluated frameworks in the form of ‘services’, is also considered to be an influence. While technology plays an important role in contemporary housing, the way it is experienced by a resident can usually be traced back to the five defined physical categories. In addition, there are elements from the three examined frameworks that fall outside the residential sphere,21 which are not included in our residential framework.

In terms of the framework as a communication tool, our proposed framework is composed of five clearly separate typological categories. Attention has been given to using a limited number of categories to accommodate communication. However, some elements inevitably fall in between certain categories. These elements can differ depending on context. For example, in urban environments, it can be argued that housing is organised more collectively, with dwellings taking the form of apartments within a large building. Here residents share collective spaces such as hallways, lifts and storage spaces. Alternatively, in rural contexts, it could be argued that dwellings often take up an entire building, which is situated on a site. The site in this case, in the form of private exterior space transitioning into public space, can be considered part of the dwelling. Therefore, we encourage the adaptation of the framework according to the specific research scope, if necessary. During the development of this framework, careful attention has been given to using lay terminology. While most of the categories presented seem to translate their meaning directly, the term ‘tectonics’ is the most demanding of prior knowledge as it stems from architectural theory. Here, the term is understood to indicate the essence of architectural expression as the result of structure, construction and space. We argue that, because of its precise meaning, it is more difficult to find a simpler synonym.

In terms of the framework acting as a research tool, it is possible that this proposed framework could serve as a basis for the analysis of research data. It could be argued that the social scope of the framework is focused on individual inhabitants rather than larger social groups such as communities. At the same time, its spatial scope is centred on the building or the scale of architecture rather than on the scale of urbanism or territories. We encourage researchers to adapt the framework to fit the specific scope of their research project if necessary. Nevertheless, we argue that the framework offers a way to relate social knowledge to the physical context of the residential environment.

We have examined existing typological frameworks of architecture and overlapped these to propose a new framework that is specifically tailored for the residential environment. By overlapping these frameworks, we have made the links to existing knowledge in architectural typology explicit. We hypothesise that, by proposing a typological framework, we can offer a way of explicitly understanding knowledge from social research within the field of architecture, essentially giving these forms of knowledge an inherently spatial characteristic, as shown in Figure 2. In this section, we will test this hypothesis by coupling research on residential experiences to specific spatial categories. A brief literature review reveals that it is possible to make explicit links between physical environments and findings from psycho-social experiences linked to dwellings.