Site constraints
The phrase site constraint normally refers to the physical constraints of a development site, such as the site boundary or surrounding features that may constrain the type of development that is possible. These constraints may also be dictated within planning policy, stating the type of development that is acceptable, known as 'planning constraints'. The development project itself may also be impacted by a number of other types of constraints, which might include legal, regulatory or environmental constraints; utility and infrastructure constraints; as well as budget constraints.
Understanding the site constraints is an important early step when planning a construction or development project, followed by or in tandem with consideration of the wider project constraints. Identifying and analysing such constraintsearly on can help ensure that a project is primarily feasible and compliant with relevant laws and regulations as well as cost-effective. The RIBA Plan of Work section 0 Strategic Definition includes what is referred to as a site appraisal, which includes different actions to be taken at the early stage of a project. These include 'site appraisal of sustainabilityopportunities and constraints of potential sites and building assets'.
Examples of physical constraints of a site might include topography, soil conditions, drainage, existing structures, and access. For example, a steeply sloping site may limit the placement of buildings or require expensive grading and retaining walls. Similarly, poor soil conditions might prevent deep foundations or require soil stabilisation. Access can be a key element in the planning of a project. If the site access is limited, it may be difficult for certain types of development or methods of construction.
Legal and regulatory constraints might include development zones of land classification, relevant building regulations, and boundary or public easements. Planning might dictate the kind of structure that can be built in terms of height, density, overlooking, parking, etc., and may also dictate the uses, such as commercial, residential, etc. Other planningaspects constraining site development could include the site classification, such as 'greyfield, 'greenfield, brownfield' or 'greenbelt. Environmental constraints might also be part of regulatory requirements and include sites with protected species, wetlands, floodplains, contaminated soils, etc.
Utility and infrastructure limitations are another important consideration. A site without access to essential utilities like water, electricity, gas, sewerage, and telecommunications may not be viable for development until those services are extended, often at significant expense. In rural areas, lack of infrastructure can be a significant constraint on residential or commercial growth.
[edit] Related articles on Designing Buildings
- Brownfield Passport.
- Concept design report.
- Construction management: feasibility studies.
- Constrained site.
- Constraints on construction projects.
- Construction site.
- Consultation on proposed reforms to NPPF and other changes to the planning system.
- Deemed discharge of planning conditions.
- Design and access statement.
- Development appraisal.
- Discharge of planning conditions.
- Feasibility studies for construction projects.
- Golden rules for the release of land.
- Grey belt.
- Main statutory considerations and constraints.
- National Planning Policy Framework.
- Planning appeal.
- Planning condition.
- Permitted development.
- Planning enforcement.
- Planning fees.
- Planning objection.
- Planning obligation.
- Planning permission.
- RIBA Plan of Work.
- Site information for design and construction.
- The grey, the brown and the golden rules of housing.
- Traditional contract: feasibility studies.
Featured articles and news
Difficult Sites: Architecture Against the Odds
Free exhibition at the RIBA Architecture Gallery until 31 May.
Designing Buildings reaches 20,000 articles
We take a look back at some of the stranger contributions.
Lessons learned from other industries.
The Buildings of the Malting Industry. Book review.
Conserving places with climate resilience in mind.
Combating burnout.
The 5 elements of seiri, seiton, seiso, seiketsu and shitsuke.
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.