- Project plans
- Project activities
- Legislation and standards
- Industry context
- Specialist wikis
Last edited 01 Oct 2020
An uplift force is any upward pressure applied to a structure that has the potential to raise it relative to its surroundings. Uplift forces can be a consequence of pressure from the ground below, wind, surface water, and so on.
Water pressure can exert an uplift force on a structure due to high rainfall, for example by causing clay soils to expand. This can be problematic if the upward forces are greater than the forces being exerted downwards by the structure. To overcome this risk, the structure must be appropriately designed to provide greater resistance against uplift forces, and also a drainage system to relieve the water pressure.
All roofs are subject to wind uplift, which will vary according to location, terrain, height, size, shape, exposure and so on. Wind uplift occurs when the air pressure under the roof is greater than the air pressure above it. This can be exacerbated during high wind, as air infiltration into the building can increase pressure below the roof, whilst the speed of wind over the roof surface can reduce air pressure above it, in much the same way it does over an aircraft wing. This can cause damage to the roof if the difference in pressure becomes too great.
'BS EN 1991-1-4:2005+A1:2010 Eurocode 1. Actions on structures. General actions. Wind actions' defines the methodology for calculating likely wind loads which then allow a roofing system to be appropriately designed.
 Related articles on Designing Buildings Wiki
- Bearing capacity.
- Floor loading.
- Ground heave.
- Hurricane design considerations.
- Lateral loads.
- Limit state design.
- Roofing defects.
- Settlement of buildings.
- The design of temporary structures and wind adjacent to tall buildings.
- Types of structural load.
- Uniformly Distributed Load.
- Wind comfort simulations.
- Wind load.
Featured articles and news
On Levelling-Up and Regeneration Bill.
Over 70 managers and organisations shortlisted for the 14 awards.
From biometric to electrical current, chemical and more.
Changes are due to come into force on 1st October 2022.
Heed advice and insight of this report IPA tells the government.
From the Commonwealth Association of Architects.
For the Levelling Up, Housing & Communities Committee.
BSRIA's Technical Director reflects on recent weather patterns.
A national valuation to fund old-age pensions.
The world’s largest Commonwealth memorial to the missing.
Long after the end of the defects liability period.
Occupant satisfaction and wellbeing in buildings.
From the simple to the complex.
And the UK Government guidelines.
Commitment agreed to by major built environment bodies.
Electrical skills, low carbon, high-tech and the building services revolution.
Ultra-deep drilling with millimeter-wave beam technology.
Looking at the built environment from space.
BSI standards 8671, 8672 and 8673.
Bringing life to burial grounds.
From failed modernism to twenty-minute neighbourhoods.
The gates process and change control.