Deconstruction

2021-12-16T09:26:26Z

Nihgxn:

[[File:BREoffice1.jpg|link=File:BREoffice1.jpg]]

= Introduction =

Deconstruction has been defined as ‘[https://www.designingbuildings.co.uk/wiki/Construction construction] in reverse’. As [https://www.designingbuildings.co.uk/wiki/Construction construction] involves assembling and erecting [https://www.designingbuildings.co.uk/wiki/Building buildings], so deconstruction is the [https://www.designingbuildings.co.uk/wiki/Complete complete] opposite: it involves taking [https://www.designingbuildings.co.uk/wiki/Building buildings] apart piece by piece, avoiding [https://www.designingbuildings.co.uk/wiki/Damages damage] by extracting carefully what is required. This contrasts with [https://www.designingbuildings.co.uk/wiki/Demolition demolition] which tends to be a relatively arbitrary and destructive process, although generally quicker.

Deconstruction is used synonymously with disassembly which has been defined as ‘non-destructive taking-apart of a construction works or constructed asset into constituent materials or components’ ([https://www.iso.org/standard/69370.html ISO 20887:2020 Design for disassembly and adaptability — Principles, requirements and guidance]) opposed to demolition which is defined as ‘removal of construction works or constructed assets by destructive methods.’

= Benefits =

Deconstruction may be chosen over demolition for various reasons, but commonly happens due to either economic reasons, site location, (e.g. [https://www.designingbuildings.co.uk/wiki/Sensitive_area sensitive area]s where [https://www.designingbuildings.co.uk/wiki/Demolition demolition] would involve danger to the immediate vicinity), preservation of items of historic/conservation interest or for environmental reasons where re-use or recycling of materials or components is prioritised. In such cases deconstruction may offer [https://www.designingbuildings.co.uk/wiki/Benefit benefits] compared to demolition such as:

* Lowering the requirement for extracting virgin [https://www.designingbuildings.co.uk/wiki/Resource resources].
* Can be a cleaner, more environmentally-friendly process with less [https://www.designingbuildings.co.uk/wiki/Pollution pollution] released into the atmosphere and into [https://www.designingbuildings.co.uk/wiki/Water water] courses.
* Can result in less [https://www.designingbuildings.co.uk/wiki/Embodied_energy embodied energy] compared to a totally new [https://www.designingbuildings.co.uk/wiki/Building building].
* [https://www.designingbuildings.co.uk/wiki/Safe Saving] [https://www.designingbuildings.co.uk/wiki/Energy energy] due to fewer [https://www.designingbuildings.co.uk/wiki/Loads loads] transported to [https://www.designingbuildings.co.uk/wiki/Site site].
* Allowing [https://www.designingbuildings.co.uk/wiki/Materials materials] to be reused or recycled and so contributes to the [https://www.designingbuildings.co.uk/wiki/Circular_economy circular economy].
* Offering controlled [https://www.designingbuildings.co.uk/wiki/Waste_management waste management].
* Reused [https://www.designingbuildings.co.uk/wiki/Materials materials] from deconstruction can offer a different [https://www.designingbuildings.co.uk/wiki/Aesthetics aesthetic] to newly [https://www.designingbuildings.co.uk/wiki/Manufactured manufactured] [https://www.designingbuildings.co.uk/wiki/Materials materials].
* Deconstruction [https://www.designingbuildings.co.uk/wiki/Activities activities] tend to be more [https://www.designingbuildings.co.uk/wiki/Labour labour] intensive therefore they can provide more jobs locally.
* Less [https://www.designingbuildings.co.uk/wiki/Materials material] goes to [https://www.designingbuildings.co.uk/wiki/Landfill landfill].

= Why deconstruct? =

Deconstruction allows the reuse of materials, which is more environmentally friendly and results in less waste going to landfill – this is critical as construction and demolition waste can comprise up to 20% of all solid waste that ends up in landfills. In addition, some materials may have become more valuable at the time of deconstruction than they were during the original construction, such as some types of brick, decorative cast iron and so on.

When materials are reused/recycled, the resulting building can have less embodied energy and so a smaller carbon footprint. Designing for deconstruction (DfD) requires that designers focus on sustainability, durability and lifecycle analysis, especially when choosing materials and ensuring that the construction process does not render future deconstruction an impractical process. High quality materials integrated into a construction that is as simple as possible can be effective as well as avoiding the use of techniques that rely on nailing and adhesives.

Deconstruction may also keep alive traditional building crafts, such as the use of lime mortars and stone dressings. Furthermore, it can provide opportunities for trainees and apprentices to learn how buildings are put together and to gain skills, such as in basic carpentry, critical thinking and teamwork.

However, not all materials can be salvaged for reuse. Of these, some can be recycled on- or off-site otherwise they may have to be taken to landfill, while hazardous materials, such as asbestos and lead paint, require expert disposal.

Deconstruction tends to be a labour-intensive process given its selective nature. It can take weeks to harvest materials from a structure, whereas demolition can be completed in as little as a day.

A typical deconstruction process involves first removing windows, doors, appliances and finishes from the structure, much of which may be reused or resold. Then the structure is dismantled, usually from the roof, through the middle floors, down to the foundations.

= DfD design principles =

Ten common principles of design for deconstruction are:

* Design for prefabrication, pre-assembly and modular construction: prefabricated units are generally easily deconstructed and can be transported in large units. Additionally, modular construction materials allow for large quantities to be transported in one journey.
* Simplify and standardise connection details: this allows for efficient construction and deconstruction and reduces the need for multiple tools.
* Simplify and separate building systems: separating out the distribution systems within non-structural walls can allow for selective removal of low-value components. Consolidating plumbing services will also reduce the lengths of pipe required.
* Consideration of worker safety: the design should aim to reduce potential hazards and the use of potentially hazardous materials.
* Minimise building parts and materials: the design should aim to minimise the number of building materials and the equipment required.
* Select fittings, fasteners, adhesives, sealants etc that allow for disassembly.
* Design to allow for deconstruction logistics: small design tweaks can allow for significant improvements in waste-removal efficiency.
* Reduce building complexity: this will reduce costs and improve buildability as well as simplifying the deconstruction process.
* Design with reusable materials: consideration of materials that are adaptable and will be useful in the future. Materials such as wood, steel members, brick and carpet tiles may be reused or refurbished.
* Design for flexibility and adaptability: the design should consider any future renovations or adaptations that may be required to extend the life of the building.

= Timber =

Timber lends itself to easier reuse than say, brick, stone or metal. The benefits of avoiding timber waste mean fewer disposal costs, a reduction in greenhouse gas emissions (methane) from decomposition. The process typically has a 33% efficiency rate: it is estimated that every three square-feet of deconstructed timber will yield around one square foot of new timber construction.

= Related articles on Designing Buildings Wiki =

* Building pathology.
* Building Revolutions - review.
* Circular economy.
* Circular economy in the built environment.
* Climate Change Act.
* Cradle to cradle product registry system.
* Decommissioning.
* Design for deconstruction.
* Design for deconstruction, BRE modular show house.
* Design for deconstruction, office building.
* Design for deconstruction, ski slope.
* Dismantling.
* Disposal.
* Emission rates.
* End of life potential.
* Energy targets.
* Examining the 2021 construction materials shortage.
* Forensic engineering in developing countries.
* Kit house.
* Lean construction.
* Mean Lean Green.
* Modular buildings.
* Off-site prefabrication of buildings: A guide to connection choices.
* Prefabrication.
* Recyclable construction materials.
* Site waste management plan.
* Structure relocation.
* Structures at the end of their design life.
* Sustainability.
* Sustainable materials

[[Category:DCN_Definition]] [[Category:DCN_Guidance]] [[Category:Construction_techniques]] [[Category:Design]] [[Category:Products_/_components]] [[Category:Circular_economy]]

Adaptability

2021-12-16T09:13:33Z

Nihgxn:

[https://www.designingbuildings.co.uk/wiki/The_SUDS_manual The SuDS Manual] (C753) published by CIRIA in 2015, defines adaptability as: (The degree to which a system can be adapted to better suit changing circumstances or conditions (see flexibility).’

Where flexibility is: ‘The ability to cope with a range of conditions or requirements.’

[https://www.urban-design-guidelines.planning.vic.gov.au/toolbox/glossary Urban Design Guidelines for Victoria], published by the State of Victoria (Australia) in 2016, defines adaptability (or 'adaptive re-use') as: ‘The capacity of a building or space to respond to changing social, technological, economic and market conditions and accommodate new or changed uses.’

In January 2020 the standard [https://www.iso.org/standard/69370.html ISO 20887:2020 Design for disassembly and adaptability — Principles, requirements and guidance] was published where the term adaptability is defined as the: ‘ability to be changed or modified to make suitable for a particular purpose.’

See also: Adapt.

= Related articles on Designing Buildings =

* SuDs.
* CIRIA.
* Resilience.
* SuDS manual.
* Sustainability.
* BREEAM Functional adaptability.
* Future proofing construction.
* Design flexibility.

[[Category:DCN_Definition]] [[Category:Definitions]] [[Category:Sustainability]]

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Deconstruction

Adaptability