Cantilever
A cantilever is a beam supported only at one end, with load carried over the overhang. This is in contrast to a simply-supported beam, which is supported at both ends.
Cantilevers provide a clear space underneath the beam without any supporting columns or bracing.
Cantilevers became a popular structural form with the introduction of steel and reinforced concrete. They are used extensively in building construction, notably in:
- Cantilever bridges.
- Overhanging elements and projections.
- Balconies, such as at Frank Lloyd Wright’s ‘Falling water’.
- Machinery and plant such as cranes.
- Overhanging roofs such as stadium roofs, and shelters.
- Shelving.
- Furniture.
Cantilever construction can be used in bridge building for crossing large spans. A simple cantilever span is constructed from two cantilever arms extending from opposite sides, and meeting in the middle. A common variation of this is the suspended span where the cantilever arms support a central truss bridge resting on the ends of the cantilever arms. A classic example of the cantilever bridge is the Forth Railway Bridge in Scotland which has three cantilevers with two connecting suspended spans.
Cantilever cranes (otherwise known as 'hammerhead crane') are hoisting cranes with a swing or fixed cantilever along which a hoisting trolley moves. They are often used in shipyards and during the construction of tall buildings.
[edit] Related articles on Designing Buildings Wiki
- Abutment.
- Adaptive structures.
- Arches.
- Barrel vault.
- Canopy.
- Concrete v steel.
- Conoid shell.
- Engineer.
- Folded plate construction.
- Flying buttress.
- Hyperbolic paraboloid.
- Moment.
- Pendentive dome.
- Point of contraflexure.
- Resonant column method.
- Shell roof.
- Structural engineer.
- Structural systems for offices.
- Substructure.
- Superstructure.
- Swing bridge.
- Types of beam.
Featured articles and news
Design and construction industry podcasts
Professional development, practice, the pandemic, platforms and podcasts. Have we missed anything?
C20 Society; Buildings at Risk List 2025
10 more buildings published with updates on the past decade of buildings featured.
Boiler Upgrade Scheme and certifications consultation
Summary of government consultation, closing 11 June 2025.
Deputy editor of AT, Tim Fraser, discusses the newly formed society with its current chair, Chris Halligan MCIAT.
Barratt Lo-E passivhaus standard homes planned enmasse
With an initial 728 Lo-E homes across two sites and many more planned for the future.
Government urged to uphold Warm Homes commitment
ECA and industry bodies write to Government concerning its 13.2 billion Warm Homes manifesto commitment.
From project managers to rising stars, sustainability pioneers and more.
Places of Worship in Britain and Ireland, 1929-1990. Book review.
The emancipation of women in art.
Call for independent National Grenfell oversight mechanism
MHCLG share findings of Building Safety Inquiry in letter to Secretary of State and Minister for Building Safety.
The Architectural Technology Awards
AT Awards now open for this the sixth decade of CIAT.
50th Golden anniversary ECA Edmundson awards
Deadline for submissions Friday 30 May 2025.
The benefits of precast, off-site foundation systems
Top ten benefits of this notable innovation.
Encouraging individuals to take action saving water at home, work, and in their communities.
Takes a community to support mental health and wellbeing
The why of becoming a Mental Health Instructor explained.
Mental health awareness week 13-18 May
The theme is communities, they can provide a sense of belonging, safety, support in hard times, and a sense purpose.
Mental health support on the rise but workers still struggling
CIOB Understanding Mental Health in the Built Environment 2025 shows.
Design and construction material libraries
Material, sample, product or detail libraries a key component of any architectural design practice.