What does in situ mean?
In situ (also referred to as insitu or in-situ) is a Latin phrase that is commonly used in the construction industry to mean ‘on site’, ‘in place’ or ‘in position’. It refers to work which is carried out on the construction site itself, often in the finished position, as opposed to in an off-site location as with prefabrication or pre-assembly techniques.
The most common use of the term 'in situ' is in relation to concrete, with components such as a slabs, beams and piles being described as ‘cast in situ’ to distinguish them from precast concrete components, that are manufactured off site.
Generally, in situ construction techniques tend to be more labour- and time-intensive, however, they are more flexible in response to changes that may arise on site. Prefabricated components, in contrast, must be designed in detail in advance, with limited scope for changes once they have been manufactured.
In situ can also be used to refer to in situ testing, for example, tests carried out on site to determine the density or shear strength of soils. For more information, see: Insitu testing of soils.
Also, in the context of soil, in situ can refer to soil which is still in its original condition and that has not been ‘cut’ from one area of a site and ‘filled’ in elsewhere.
See also: On site.
[edit] Related articles on Designing Buildings
Featured articles and news
Shading for housing, a design guide
A look back at embedding a new culture of shading.
The Architectural Technology Awards
The AT Awards 2025 are open for entries!
ECA Blueprint for Electrification
The 'mosaic of interconnected challenges' and how to deliver the UK’s Transition to Clean Power.
Grenfell Tower Principal Contractor Award notice
Tower repair and maintenance contractor announced as demolition contractor.
Passivhaus social homes benefit from heat pump service
Sixteen new homes designed and built to achieve Passivhaus constructed in Dumfries & Galloway.
CABE Publishes Results of 2025 Building Control Survey
Concern over lack of understanding of how roles have changed since the introduction of the BSA 2022.
British Architectural Sculpture 1851-1951
A rich heritage of decorative and figurative sculpture. Book review.
A programme to tackle the lack of diversity.
Independent Building Control review panel
Five members of the newly established, Grenfell Tower Inquiry recommended, panel appointed.
Welsh Recharging Electrical Skills Charter progresses
ECA progressing on the ‘asks’ of the Recharging Electrical Skills Charter at the Senedd in Wales.
A brief history from 1890s to 2020s.
CIOB and CORBON combine forces
To elevate professional standards in Nigeria’s construction industry.
Amendment to the GB Energy Bill welcomed by ECA
Move prevents nationally-owned energy company from investing in solar panels produced by modern slavery.
Gregor Harvie argues that AI is state-sanctioned theft of IP.
Experimental AI housing target help for councils
Experimental AI could help councils meet housing targets by digitising records.
BSRIA Occupant Wellbeing survey BOW
Occupant satisfaction and wellbeing tool inc. physical environment, indoor facilities, functionality and accessibility.