Anticlastic structures
Tensile surfaces, that is, surfaces which carry only tension and no compression or bending, rely on double curvature for their stability. Stability is provided by the opposition of two curvatures which enable the surface to be tensioned without losing its form.
Tensioning the surface reduces its elasticity and so its tendency to deform under load, and the curvature itself means that the surface will deform less for any given extension.
Tensile surfaces can be used in buildings to create thin, long span enclosures, such as roofs for sports stadia, shopping centres, atria and so on. Typically they are constructed using a PVC coated polyester or PTFE coated glass fabric, typically just 1 mm thick.
Double curvature can be anticlastic or synclastic.
![]() |
![]() |
Anticlastic (saddle-shaped). | Synclastic (dome-shaped) |
Anticlastic surfaces are those in which the centres of curvature are located on opposing sides of the surface. This is commonly-described as a saddle shape. A hyperbolic paraboloid is an anticlastic surface.
Synclastic surfaces are those in which the centres or curvature are on the same side of the surface. This is a dome-shape. This can be created with an architectural fabric by inflation – that is, air pressure within the dome maintains the form of the surface when it is tensioned, rather than the opposition of the curvatures.
[edit] Find out more
[edit] Related articles on Designing Buildings Wiki
- Barrel vault.
- Biaxial bending.
- Concept structural design of buildings.
- Conoid shell.
- Fabric structures.
- Hyperbolic paraboloid.
- Limit state design.
- Millennium Dome.
- Structural engineer.
- Synclastic.
- Tensegrity.
- Tensile structures.
- The development of structural membranes.
- The structural behaviour of architectural fabric structures.
- Types of dome.
[edit] External references
- ‘How structures work: Design and behavior from bridges to buildings’ (2nd ed.), YEOMANS, D., Wiley (2016)
Featured articles and news
Retrofit 25 – What's Stopping Us?
Exhibition Opens at The Building Centre.
Types of work to existing buildings
A simple circular economy wiki breakdown with further links.
A threat to the creativity that makes London special.
How can digital twins boost profitability within construction?
The smart construction dashboard, as-built data and site changes forming an accurate digital twin.
Unlocking surplus public defence land and more to speed up the delivery of housing.
The Planning and Infrastructure Bill
An outline of the bill with a mix of reactions on potential impacts from IHBC, CIEEM, CIC, ACE and EIC.
Farnborough College Unveils its Half-house for Sustainable Construction Training.
Spring Statement 2025 with reactions from industry
Confirming previously announced funding, and welfare changes amid adjusted growth forecast.
Scottish Government responds to Grenfell report
As fund for unsafe cladding assessments is launched.
CLC and BSR process map for HRB approvals
One of the initial outputs of their weekly BSR meetings.
Architects Academy at an insulation manufacturing facility
Programme of technical engagement for aspiring designers.
Building Safety Levy technical consultation response
Details of the planned levy now due in 2026.
Great British Energy install solar on school and NHS sites
200 schools and 200 NHS sites to get solar systems, as first project of the newly formed government initiative.
600 million for 60,000 more skilled construction workers
Announced by Treasury ahead of the Spring Statement.
The restoration of the novelist’s birthplace in Eastwood.
Life Critical Fire Safety External Wall System LCFS EWS
Breaking down what is meant by this now often used term.
PAC report on the Remediation of Dangerous Cladding
Recommendations on workforce, transparency, support, insurance, funding, fraud and mismanagement.
New towns, expanded settlements and housing delivery
Modular inquiry asks if new towns and expanded settlements are an effective means of delivering housing.