Lintel
A lintel is a structural horizontal support used to span an opening in a wall or between two vertical supports. It is frequently used over windows and doors, both of which represent vulnerable points in a building's structure. Lintels are generally used for load-bearing purposes, but they can also be decorative.
The most common materials for lintels are timber, steel and concrete.
Timber is low cost, readily available and can be easily cut to size on site. However, it is generally only suited to small openings with low loadings.
Precast concrete lintels are economical and provide robust support for structures such as masonry over door and window openings. They are able to accept a wide range of surface finishes.
Steel lintels are generally made from pre-galvanised steel which is cut and either roll-formed or pressed into the required shape. Steel has the advantage over concrete in that the lintels are usually lighter and are easier to handle on site. The lintel can be shaped so that it is not visible above the opening. Steel is also versatile and can be custom-produced according to the specific building requirement, whether arched, in a corner, forming a bay window, and so on.
In order to specify the type of lintel required, the nature of the load to be supported must be calculated. This includes both dead and imposed loads. Dead loads refer to the static mass of the building components such as floor coverings, roof tiles, masonry, and so on, whereas, imposed loads refer to the weight of furniture, fittings, people and so on.
Lintels must have adequate support at each end, and typically, the length of lintel for a masonry wall is calculated by measuring the total width of the structural opening, and adding 150 mm for end-bearings at each end. If lintels or end-bearings are inadequate specified, they can cause cracking in decorations, or in the structure itself, and ultimately can cause structural failure and collapse.
Lintels are also important in terms of their role in reducing heat loss from a building and the occurrence of damp and condensation. Lintels must be designed and constructed carefully to avoid thermal bridging (a direct connection between the inside and outside through elements that are more thermally conductive than the rest of the building envelope). This may include the creation of a cavity within the wall above the lintel, and the insertion of insulation.
Lintels may also need to incorporate a cavity tray or damp proof membrane to direct water within the wall or cavity to the outside through weep holes. Stop ends at either end of lintels prevent water flowing off the end of the lintel back into the cavity where it may dampen the inside wall.
[edit] Related articles on Designing Buildings
- Architrave.
- Barrel vault.
- Braced frame.
- Cavity tray.
- Concept structural design of buildings.
- Concrete-steel composite structures.
- Concrete vs. steel.
- Damp proof membrane.
- Jamb.
- Long span roof.
- Mullion.
- Reinforced concrete.
- Spandrel.
- Specifying steel lintels.
- Structural engineer.
- Structural steelwork.
- Stud.
- Thermal bridging and the Future Homes Standard.
- Transom.
- Types of brick arches.
- Weep hole.
- Window.
- Window frame.
- Window sill.
Featured articles and news
The UK's Modern Industrial Strategy: A 10 year plan
Previous consultation criticism, current key elements and general support with some persisting reservations.
Building Safety Regulator reforms
New roles, new staff and a new fast track service pave the way for a single construction regulator.
Architectural Technologist CPDs and Communications
CIAT CPD… and how you can do it!
Cooling centres and cool spaces
Managing extreme heat in cities by directing the public to places for heat stress relief and water sources.
Winter gardens: A brief history and warm variations
Extending the season with glass in different forms and terms.
Restoring Great Yarmouth's Winter Gardens
Transforming one of the least sustainable constructions imaginable.
Construction Skills Mission Board launch sector drive
Newly formed government and industry collaboration set strategy for recruiting an additional 100,000 construction workers a year.
New Architects Code comes into effect in September 2025
ARB Architects Code of Conduct and Practice available with ongoing consultation regarding guidance.
Welsh Skills Body (Medr) launches ambitious plan
The new skills body brings together funding and regulation of tertiary education and research for the devolved nation.
Paul Gandy FCIOB announced as next CIOB President
Former Tilbury Douglas CEO takes helm.
UK Infrastructure: A 10 Year Strategy. In brief with reactions
With the National Infrastructure and Service Transformation Authority (NISTA).
Ebenezer Howard: inventor of the garden city. Book review.
The Grenfell Tower fire, eight years on
A time to pause and reflect as Dubai tower block fire reported just before anniversary.
Airtightness Topic Guide BSRIA TG 27/2025
Explaining the basics of airtightness, what it is, why it's important, when it's required and how it's carried out.
Construction contract awards hit lowest point of 2025
Plummeting for second consecutive month, intensifying concerns for housing and infrastructure goals.
Understanding Mental Health in the Built Environment 2025
Examining the state of mental health in construction, shedding light on levels of stress, anxiety and depression.
The benefits of engaging with insulation manufacturers
When considering ground floor constructions.
Lighting Industry endorses Blueprint for Electrification
The Lighting Industry Association fully supports the ECA Blueprint as a timely, urgent call to action.