Building transformation: concepts and definitions
Adaptation covers a wide range of perspectives and its definition is very context specific. In terms of construction projects adaptability is often used as a synonym for flexibility, though the latter might imply fewer or lighter structural changes  as well interchangeable elemental, modular or component parts. More recently adaptation can be found with reference to environmental performance both internally (adaptive comfort) and externally (climate adaptation). The term adaptation can be roughly described as any adjustment to an existing building (over and beyond standard maintenance), its structural or non-structural fabric and layout. The purpose of adjustment being rehabilitation, changes in capacity, function or performance eventually extending a building’s life or increasing its value (in economic, social, environmental and aesthetical senses). In literature the term adaptation has been used to cover changes in use, physical layout and size. It also covers interventions to building components or materials and their reuse. Building adaptation might be roughly divided into building refurbishment and adaptive reuse, which can then be further divided into several other subcategories. [12, 13, 18]
Refurbishment derives from the Latin words re (again) and furbish (to polish) and might describe a broad range of activities to improve current conditions of use or appearance, from deep cleaning or decoration to reconfiguration and replacement. In more formal terms the scope of interventions range from ‘improving environmental and operating costs’ to ‘repair work, renovations and alterations, and the structural rehabilitation’ of existing buildings . These activities may be carried out in cycles as part of an ongoing management approach of developing, operating, maintaining, upgrading and disposing of assets, such as buildings (asset management). Increasingly, the term specifically covers additions which are made to improve energy or environmental performance (e.g. in-use energy efficiency and operating costs) of existing buildings . However on the whole, refurbishment covers a wide range of interventions that aim to prolong the useful life of a building, which may include what might be considered aesthetic improvements, that often go beyond simple maintenance, repair work, and alteration. [13, 14, 18]
 Retrofitting of buildings / retrofit
Retrofit involves the addition of elements or parts available after initial manufacture, installation or completion. In buildings terms this often involves the non-structural addition of new materials and elements to the existing fabric of a building. This will quite often relate to the redesign, reconstruction (whole or partial) or reconfiguration of existing technical services ( such as lighting, heating, cooling or ventilation) in order to meet new requirements, regulations or needs. The level of retrofit maybe described through additional terms such as in the case of deep retrofit. The goals of these changes might include for example improving energy efficiency (e.g. reducing fabric energy losses, improving the efficiency of heating, ventilation and air conditioning systems) or improving performance (e.g. improving internal air quality with actuated windows). They may also include safety and comfort in use ( e.g. smoke detectors or carbon dioxide monitors) or increased accessibility (e.g. adding a lift or accessibility ramp). [10, 18] Guidance and even standards may be adjusted for the specific case of retrofit such as energy standards or access according to the disability discrimination act (DDA) for listed and historic buildings.
 Renovation of buildings / renovate
Renovation derives from the Latin words re (again) and novare (make new). Generally, it can be defined as the process of cleaning, changing, replacing or repairing outdated components or remodelling, for example the interior spatial layout of an existing building, or its external facade, to bring it (back) into good condition. Hence, renovation means to improve a building’s state while not necessarily restoring it to a former state. It can include structural and non-structural interventions and is most commonly used as a broad building term in European countries. As it is a general term that has local differences in definition, it is seen as somewhat unpopular in the academic context. [13, 18]
 Building rehabilitation / rehabilitate
Rehabilitation addresses the need to substantially improve failing features of a building so that it can provide a compatible use, this will mainly involving the repair, alterations, additions or restoration of portions that convey historical, cultural or architectural value. The term to some extent assumes that the existing building has fallen into such a state of repair that it needs work in order to prevent further damage, the goal of the works are to bring it into a compatible contemporary use (as opposed to being purely repaired or restored). As such the works such as strengthening or replacement of a structure do so in a way that ‘returns its performance to levels approaching or exceeding those of a newly constructed facility’ . In some cases, the terms cover an update of building systems to the latest building regulations. [10, 18] The term is perhaps more commonly used in the US construction industry, but is also used and understood in the UK. Should not be confused with buildings that are rehabilitation facilities, which describes the social function of a building to rehabilitate users after an illness or injury through various type of therapy or treatment. See also regeneration which applies to the urban context.
Conversion includes the reuse of an existing building for a use different from the one for which it was originally designed with the aim of ‘extending the useful life of old, historic, obsolete, and derelict buildings’ . Adaptive reuse, repurposing and conversion are often used interchangeably. The term conversion is a more formal term that refers explicitly to changes that involve a functional and a physical component. [10, 13, 18] Conversions from industrial to residential or commercial, residential to commercial and commercial to any other type are among the most commonly reported types of conversion found in the literature. Conversion bears high risks regarding return on investment and is therefore often disregarded as a potential alternative to demolition by owners and investors. Adaptive reuse aswell as repurposing can also refer to the reuse of building materials and components, as it does in Shahi et al. (2020), but this is not the standard use for the term.
 Transformation / transformative
Transformation is an umbrella term for various kinds of comprehensive adaptation and refurbishment activities, often but not exclusively seen in the positive sense of improvement. The term may be related to transformative deisgn, which can be described as human-centred design that seeks to create positive environments that can impact towards positive behavioural change. From a functional perspective the term usually indicates a notable change in the use of a building, either through change of function(s) or significant alterations to the current function(s) via e.g. spatial rearrangements. In addition, the term may be applied to actions that do not directly affect the use of the building but otherwise majorly alter e.g. its appearance or technical performance, such as thorough façade renovation.
In construction the term could refer to specific products or elements of a building as well as the end-of-life of the whole building. It may be understood as being the result of physical deterioration, technological advances or changes in preferences. More explicitly it may refer to the growing divergence between rising demand side expectations due to technological advances on the one side, and declining performance on the other.
The reasons for obsolescence might include:
- The degradation or fatigue of materials over time, through insufficient maintenance, overload, overuse, misuse or maltreatment.
- Physical impacts of nearby construction, rising standards and government regulations may amplify the onset of obsolescence, in the surroundings or building locations.
- Changes in function, use or needs that cannot be accommodated within the existing design.
- Social deprivation processes, criminality, availability or simply aesthetics as external behavioural factors.
Modularity involves the use of repetitive components and subsystems  that often allow a speedy assembly or disassembly, maintenance and replacement. National or international codes often regulate or have an indirect impact on dimensions (e.g. the dimensions of ship containers or lorries), in addition to which modules are custom size and system-specific. Modular buildings may be divided into building into zones or elements that can allow for greater control and efficiency in production, installation and use, which in turn can lead to economic and environmental efficiencies.
 Building life cycle
The life cycle of a building begins with the extraction of the raw materials used for its construction and continues until the eventual demolition and subsequent disposal, reuse, or recycling of its components or materials. Within this span, the life cycle can be divided into distinct phases. The specific terminology varies, but overall the following phases are distinguished: the product phase (extraction and processing of materials into usable products), the construction phase (erecting the building), the use phase (use of the building, including maintenance), the end of life phase (demolition and related handling of the building’s materials and components), and ideally the ‘beyond’ phase, when materials and components extracted from the building are further used. [5, 10, 21]
The service life of a building comprises the use phase of a building’s life cycle  over which at least an acceptable minimum level of shelter or service, as defined by the owner, is provided . Furthermore, service life can be understood as the period of time over which parts of a building meet or exceed performance requirements  including technical, economic, functional, or even aesthetic aspects. For example, the economic life of a building is ‘the period of time over which costs are incurred and benefits or disbenefits are delivered to an owner; […] not necessarily related to the likely [technical] service life of a facility or subsystem.’  The service life of a building can be extended through maintenance, refurbishment, and adaptation, depending on case specific needs. Different parts of a building can have different service lives. For example, building services equipment are likely to require replacement due to technical ageing before the structural building frame does. On the other hand, through reuse of materials and components the service life of some building parts may exceed the original use phase of the building.
The foundation for building preservation was laid in the 19th century with two distinct movements; ‘restoration movement’ as argued by e.g. Eugène Viollet-le-Duc and the ‘anti-restoration’ or ‘conservation’ movement as supported by e.g. John Ruskin. Both approaches aim for the ‘protection of historic buildings and works of art’ , yet methods and objectives are often conflicting. Both movements intend to safeguard monuments as historical evidence. Generally speaking, preservation means to keep an existing building from falling into decay and protecting it from irredeemable damage, alterations and changes. [1, 6, 7, 14]
Also called the ‘anti-restoration movement’, conservation is the maintenance of an absolute maximum of the original building material in as unaltered condition as possible. Maintenance on a permanent basis is the essence of conservation by ‘making use of [the architectural work] for some socially useful purpose’ . During reparation or modifications required by a functional change, as little as possible of the original materials may be removed or altered and most of the work (including additions) on the building must be reversible with minimal impact on its condition or layout. In conservation, history and setting are inseparable from the architectural monument which does not allow the moving of the monument or alterations made to the relations of mass and colour. [7, 14]
According to Davies & Jokiniemi (2008), restoration is ‘the action of bringing a building […] to its original state by repair work, cleaning etc.’. Moreover, restoration aims not only to preserve but also reveal the aesthetic and historic value of a monument by bringing it into a condition of potentially unprecedented completeness. Unlike conservation, it allows replacing and even adding elements which are to be integrated harmoniously into the whole. Whether this means that new and old should be distinguishable is disputable. For example, ICOMOS (1964) argues for a clear distinction while Viollet-le-Duc’s restoration practice often included additions made to fit the same style as the original. Restoration also allows repair work to be executed by using reclaimed building parts to replace missing originals which opens new possibilities for potentially more sustainable alternatives to the use of virgin materials. However, free space for reinterpretations of architectural heritage leads to what anti-restorers often call falsification. [2, 7, 9, 14]
- Building adaptation.
- National Adaptation Programme.
- Resilient adaptation.
- Future proofing construction.
- Design flexibility.
- Comprehensive refurbishment.
- Energy efficiency retrofit training videos.
- Loft conversions.
- Alterations to existing buildings.
- Upcycling buildings.
- Remedial work.
- Design for deconstruction.
- Design for Manufacture and Assembly (DfMA).
- Flat pack.
- Kit house.
- Modern methods of construction.
- Modular buildings in the educational sector.
- Modular classrooms: The Friars Primary School extension.
- Modular construction market report 2020-2026.
- Modular housing and electrical circuitry.
- Volumetric modular construction.
- Ashworth, A. (2012). Preservation, Conservation and Heritage: Approaches to the Past in the Present through the Built Environment. Asian Anthropology, 10(1), 1-18. https://doi.org/10.1080/1683478X.2011.10552601
- Denslagen, W. (1994). Architectural Restoration in Western Europe: Controversy and Continuity. Amsterdam: A&NP.
- Davies, N., & Jokiniemi, E. (2008). Dictionary of Architecture and Building Construction. 2nd edition. Architectural Press.
- Gosling, J., Naim, M., Sassi, P., Iosif, L. & Lark, R. (2008). Flexible buildings for an adaptable and sustainable future. Association of Researchers in Construction Management, ARCOM 2008 - Proceedings of the 24th Annual Conference. 1. 115-124.
- Hasik, V., Ororbia, M., Warn, G.P., & Bilec, M.M. (2019). Whole building life cycle environmental impacts and costs: A sensitivity study of design and service decisions. Building and Environment 163(106316). https://doi.org/10.1016/j.buildenv.2019.106316
- Huuhka, S. & Vestergaard, I. (2019). Building conservation and the circular economy: a theoretical consideration. Journal of Cultural Heritage Management and Sustainable Development 10(1), 29–40. https://doi.org/10.1108/JCHMSD-06-2019-0081
- ICOMOS. (1964). Venice Charter: International Charter for the Conservation and Restoration of Monuments and Sites. Article 5. Venice.
- International Organization for Standardization (ISO) (2000). ISO 15686-1. Building and Constructed Assets – Service. Life and Planning – Part 1: General Principles, ISO, Geneva.
- Kalakoski, I. & Huuhka, S. (2018). Spolia revisited and extended: The potential for contemporary architecture. Journal of Material Culture 23 (2), 187-213. https://doi.org/10.1177/1359183517742946
- National Research Council (1993). The fourth dimension in building: Strategies for minimizing obsolescence. Washington, DC: The National Academies Press. https://doi.org/10.17226/2124
- National Research Council (1993). The fourth dimension in building: Strategies for minimizing obsolescence. Washington, DC: The National Academies Press. https://doi.org/10.17226/2124. p. 68.
- Pinder, A., Schmidt, R., Austin, S., & Gibb, A. (2016). What is meant by adaptability in buildings? Facilities 35(1/2), 2–20.
- Plevoets, B. & van Cleempoel, K. (2019). Adaptive reuse of the built heritage: concepts and cases of an emerging discipline. https://doi.org/10.4324/9781315161440
- Rouhi, J. (2016). Development of the Theories of Cultural Heritage Conservation in Europe: A Survey of 19th And 20th Century Theories.
- Rouhi, J. (2016). Development of the Theories of Cultural Heritage Conservation in Europe: A Survey of 19th And 20th Century Theories. p. 1.
- Rauf, A., & Crawford, H. (2015). Building service life and its effect on the life cycle embodied energy of buildings. Energy 79, 140–148. https://doi.org/10.1016/j.energy.2014.10.093
- Schwartz, Y., Raslan, R., Mumovic, D. (2016). Implementing multi objective genetic algorithm for life cycle carbon footprint and life cycle cost minimisation: A building refurbishment case study. Energy 97, 58-68. http://dx.doi.org/10.1016/j.energy.2015.11.056
- Shahi, S., Esfahani, M., Bachmann, C., & Haas, C. (2020). A definition framework for building adaptation projects. Sustainable Cities and Society 63(102345). https://doi.org/10.1016/j.scs.2020.102345
- Shahi, S., Esfahani, M., Bachmann, C., & Haas, C. (2020). A definition framework for building adaptation projects. Sustainable Cities and Society 63(102345). https://doi.org/10.1016/j.scs.2020.102345. p. 5.
- Shahi, S., Esfahani, M., Bachmann, C., & Haas, C. (2020). A definition framework for building adaptation projects. Sustainable Cities and Society 63(102345). https://doi.org/10.1016/j.scs.2020.102345. p. 9.
- Sharma, A., Saxena, A., Sethi, M., Shree, V., & Varun. (2011). Life cycle assessment of buildings: A review. Renewable and Sustainable Energy Reviews 15(1), 871–875. https://doi.org/10.1016/j.rser.2010.09.008
- Thomsen, A., & van der Flier, K. (2011). Understanding obsolescence: a conceptual model for buildings. Building Research and Information 39(4), 352–362. https://doi.org/10.1080/09613218.2011.576328
- Loft conversions.
- Construction of a basement.
- Redesign of floor plans.
- Re-wiring, re-plumbing, new drainage lines and so on.
Cosmetic renovation might include:
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