What is a Lintel and What Are the Different Types of Lintels?

A lintel is a part of the supporting structure of a building wherever there is a requirement for an opening within a wall. A lintel can be made from steel, reinforced concrete, and sometimes, in a timber framed structure, wood.

There are a wide range of lintel types, sizes and duties to cater for every specification of opening size and supportable load. At its most basic it is a beam that helps to transfer overhead weight safely to the foundations.

You will need a lintel when you want to create a new window, or doorway, perhaps you would like to open up the interior of a house or build an extension. In every case you will require a lintel in one form or another to create the opening.

What Does a Lintel Do?

A lintel has a specific role to play in construction, to carry the load above windows and doors. Some lintels are made to be seen, a feature of the property design, while others are more covert, supporting face brickwork.

If you are experiencing difficulty using a window or door, perhaps there is some friction at the top and bottom of the frame, it could be that the lintel has failed. When this happens, the load may be being transferred through the door or window frame, causing it to distort.

It’s a good early warning that something might be structurally wrong. Check above the door or window for any signs of movement, such as cracked render, or failed mortar joints. It may be time to replace your lintel.

What Are the Different Types of Lintel?

The most commonly used lintels in the UK are made from either reinforced concrete, or steel. These lintel types are used extensively throughout the British construction industry on every kind of building project.

Reinforced concrete lintels are typically less expensive than steel, but both have their good and bad points. Lintel construction these days comes down to a number of factors, strength and stability being foremost.

• Some older buildings may boast timber or stone out front, but many will be backed up by modern methods of construction behind the scenes.

• The fancy traditional features surrounding windows on many new developments are often stone-finished polystyrene, simply glued directly to the wall.

• In timber framed houses the internal walls will have thick wooden beams called headers spanning doorways, or steel beams over wider openings.

How Do I Choose Which Lintel to Use?

On a new construction project, it will fall to your structural engineer to specify the particular rating of lintel required, standard, heavy, or extra-heavy duty. The architect may advise whether concrete or steel is preferable depending upon the aesthetics of the build.

On an existing building, it is always a good idea to match the existing method of construction, if it is compatible with modern specifications. If your property is listed, or in a conservation area, there may be restrictions on what you are able to do.

A good rule of thumb to remember is that steel is usually first choice for the widest openings, as it can maintain rigidity over longer spans than concrete. If in doubt, always consult a structural engineer, and your local authority.

What is a Reinforced Concrete Lintel?

Reinforced concrete lintels are incredibly durable and are often used below ground in order to bridge over incoming services, and outgoing drainage runs. Concrete has excellent compressive strength, which means that it can withstand heavy crushing forces.

However, it doesn’t have great tensile strength, which means that if it bends, it will likely break. This is where reinforcement, in the shape of steel rods, comes in.

Because steel and concrete have very similar heat transfer properties, it means that they move at the same rate, expanding and contracting together when the weather changes. This means that the concrete, reinforced with steel rods, becomes imbued with steel’s tensile properties.

Where Can I Use Concrete Lintels?

Concrete lintels are excellent in all standard masonry construction. They take render well on the outside of a building, and plaster on interior walls too. If your interior partition walls are built with blockwork, a concrete lintel could be your first choice.

Because of exposure to water, moisture, earth, or other poor conditions, a concrete lintel will do better than steel at any level below the damp proof course. Reinforced concrete lintels are also very cost-effective, so will help maintain a healthy bottom line.

Using concrete lintels to cap openings in cavity walls can help to minimise cold bridging too. With a lintel on each leaf, the masonry overhead is supported, the inner and outer wall only connected by a cavity tray.

Pro Tip

You can cut concrete lintels to size, so they are easy to modify if you have a bespoke size opening to deal with. It is also possible to use off-cuts that are the right size, as padstones, to deliver additional structural support.

What are the Problems with Concrete Lintels?

Concrete lintels aren’t designed to be pretty. They are no nonsense, here to get a job done.  On some projects, this isn’t an issue, but for larger spans the depth required for a concrete lintel could also make them heavy, and harder to transport and install.

If a concrete lintel is used in a maritime environment it may require additional protection from the elements. A concrete lintel that has been cut to size may have exposed reinforcement at either end.

It is often not an issue, however, if it is exposed to too much moisture, rust can make the steel expand inside the concrete, and the lintel will fail. Protect it with the right level of mortar cover.

Why Should I Use A Steel Lintel?

Steel lintels are incredibly versatile, extremely strong, and have advanced a long way technologically since their introduction into the UK construction sector in the 1960s. A steel lintel will be light, and easy to transport too.

I would advise using a steel lintel when there is a need to support face brickwork, or a decorative stone, or timber lintel. Steel is perfect when supporting a soldier course of vertical, feature brickwork.

For wider spans, steel comes into its own as a structural solution. If you are installing a folding or sliding doorset to the rear of a property, or a series of picture windows, steel has the strength to deliver an elegant solution.

What Types of Steel Lintel are Best?

Thermally broken steel lintels are ideal for new construction where Part L Building Regulation compliance is key. They can often solve the problem of cold bridging in cavity walls. Used with cavity closers a thermally broken lintel will contribute hugely to your EPC rating.

Steel cavity wall lintels come with a built-in cavity tray, to help direct moisture out of the building. If you select one with a thermal break, the moulded insulation will do the same job, just don’t forget the weep vents to let the moisture out.

Pro Tip

I would choose a cavity lintel over concrete for a front door frame to ensure stability across the cavity. As an area that would experience regular, frequent use, I would prefer to be confident that both the inner and outer leaf remained aligned over time.

Where Else Can I Use Steel Lintels?

Box steel lintels are a good choice for internal blockwork walls as they can take plaster directly. Again, they are ideal for wider spans, for open-plan designs, and are easier to handle than concrete counterparts.

Light gauge lintels that span narrow openings are inexpensive discreet supports for brickwork above utility cabinets.

Rolled steel joists (RSJs) or universal beams are popular when opening up larger structural openings, or when taking down internal supporting walls when remodelling.

Get in touch today and speak to our professional team. Whatever your lintel requirements, at Wade, we can deliver the support you need, right to your door.