These cavity lintels are all thermally insulated and galvanised for longer life, with a built-in key for plaster finishes. Perfect for double-skin fair-face masonry walls.

What Duty Cavity Lintel Do I Need?

Standard Duty 150mm Cavity Lintel

The standard gauge lintel will take on your basic masonry loads that comfortably triangulate over the opening. This means that on either side of the opening, there is at least 600mm of masonry (two feet) and that there are no obstructions above.

An obstruction might be a window or other opening that falls within a triangle of masonry directly overhead.

Depending upon the level of obstruction and the proximity of other openings or loadings you might require a medium-duty lintel.

Medium Duty 150mm Cavity Lintel

A medium-duty cavity lintel can get over most minor obstructions and is rated to carry higher loads than the standard specification. Check the load span tables to make sure the lintel matches the load.

Medium-duty lintels sometimes need to be ordered in advance as they are often made to order. It may be quicker to go for a heavy-duty steel lintel instead.

To help read the load span tables to make sure you are getting the right product, check out this guide from Stressline.

Heavy Duty Cavity Lintels and Extra Heavy Duty

For wider spans and openings below concrete floors or attic trusses, it could be time to upgrade to a heavy-duty or extra-heavy-duty lintel.

These steel lintels can take some serious loading. The Stressline SL150CXHD225 can comfortably span a 4.8m opening, as long as it is propped until the masonry has cured, to prevent flexing.

Structural Steel Lintel Specifications

If you have any concerns as to which is the correct lintel to use our team will be happy to help.

However, a structural engineer can specify which lintel would be most appropriate, saving you the worry, and the cost of replacement, or the added cost of over-specifying.

Couple the lintels with cavity closers to complete the opening ready for the window or door fitting team. Simple to cut and fit, and Building Control and NHBC compliant, they will give your masonry a professional finish.