What it is called, by market
One concept, four markets. Where a name means something else locally, the card says so rather than leaving you to find out on site.
United Kingdom
Close, not identicallintel
also cavity lintel, box lintel, catnic
Usually a manufactured steel section or a precast concrete unit rather than timber, and in a cavity wall a single lintel commonly spans both leaves and carries a damp-proof tray.
Australia
Close, not identicallintel
also head beam, galvanised lintel
As the UK for masonry, but in timber-framed construction the member over an opening is frequently called a head or head trimmer instead.
United Statesyours
Same word, different thingheader
also door header, window header, lintel
In British usage a header is a brick laid with its end showing, a header tank is a cold-water cistern, and a header is a pipework manifold. None of them spans an opening.
Canada
Same word, different thingheader
also lintel, built-up header
As the United States, with lintel reserved more often for masonry and header used for the timber member in framing.
The governing standard, by market
United Kingdom
BS EN 845-2
Specification for ancillary components: lintels, including their load classification and testing.
United States
IRC Table R602.7
Prescriptive header spans for wood framing, by species, size and loading condition.
Calculators for this
Each works in either measurement system, and the terminology on the page follows whichever market you have selected.
Frequently asked questions
- Does a header mean the same thing as a lintel?
- Structurally yes, materially usually not, and the word itself is a trap in British usage. Both name the member spanning an opening and carrying what sits above it. But an American header is typically built up from dimensional lumber — two or three members nailed together with packing between them, sized from a span table — whereas a British lintel is generally a manufactured steel profile or a precast concrete unit selected from a manufacturer's load tables. So converting a specification is not a matter of swapping the word: a timber header span table has no entry for a cavity-wall steel lintel, and the British lintel additionally carries a damp-proof tray across the cavity that the timber member never had to. And in British usage the word header is already taken three times over, by a brick laid end-on, a cold-water cistern and a pipework manifold.
- What is bearing length, and why does it get specified separately?
- It is how far the lintel sits onto the wall at each end, and it is a separate check because the lintel can be strong enough while the masonry under its ends is not. The load the lintel collects has to pass into the wall through that contact area, so a short bearing concentrates the same force over less masonry and can crush it — which is why manufacturers state a minimum bearing, commonly 100 mm or 150 mm depending on the span and load, and why a padstone appears under a heavily loaded end. It also changes the ORDER LENGTH: the lintel you buy is the clear opening plus two bearings, so a 1,800 mm opening with 150 mm bearings needs a 2,100 mm lintel. Ordering to the opening size is one of the commonest measuring errors on a job.
- Why do lintels over cavity walls look so different from solid-wall ones?
- Because they are doing a second job as well as spanning. A cavity wall has two leaves with a gap between them, and water that crosses the outer leaf has to be caught and sent back out rather than reaching the inner leaf. So a cavity lintel is profiled to support both leaves and to act as a tray, with a rise across the cavity and stop ends, and weep holes are left in the perimeter joint above it so the collected water can escape. A solid-wall lintel only has to span. That is why a cavity lintel is specified by the wall build-up it suits — cavity width, leaf thicknesses, insulation — and not by span and load alone.