By Chris 1 February 2024

What is a Door Lintel and Why Is It So Important

What is a Door Lintel and Why Is It So Important

If you’re looking to add an extra door to your property, knowing what a door lintel is could be handy.

This post talks about what a door lintel is and the different types, what size of lintel you need, installing and replacing a door lintel and our final words.

What Is A Door Lintel?

If you’re adding an additional door to your property, you need to remove some of the house bricks to make the opening. The question is, what holds up the bricks at the top of the doorway.

The door lintel is a horizontal beam fitted across the top of the door opening to support the bricks above the door structurally.

Over the years, lintels have been made from numerous materials, but today they are typically made from steel or prestressed concrete, depending on the door opening’s size.

Depending on the door lintel location, it can be decorative, and therefore you may find lintels that have been patterned in some way.

Do You Need A Door Lintel?

If the work that you’re carrying out on your property compromises the structural integrity, then a lintel is required.

The lintel material used will depend on the structure of your property. Timber-framed buildings need load-bearing support, and therefore you may need additional lintel support.

If the building has sufficient support in the door’s location, you may not need to fit more lintels. However, these days they are required as part of today’s building regulations.

For all openings using timber frames over a width of 600 mm, and all openings using steel frames over 900 mm, then lintels are needed.

In addition to lintels, other building reinforcing measures may be required to ensure the masonry above the door opening becomes a solid mass to suitably take the load on either side of the opening.

Types Of Lintels


Many years ago, Timber was used for lintels as the materials were readily available. However, today Timber is more costly and less durable compared to modern-day materials. Wood has safety concerns where it can be subject to fire.


Stone lintels have been the most common material used over the years, with the thickness being the most critical feature, and can be used as either one piece or several pieces.


Brick lintels are used for lower loads and when the opening is typically less than 1 metre. Bricks with frogs are best used as the frogs filled with cement provide more shear resistance, known as juggled brick lintel.


Reinforced brick lintels are typically used when the span is more than 1 metre and for heavy loads. The bricks are positioned to allow for 2 to 3 cm spacing between bricks to insert mild steel bars as additional reinforcement.


Steel lintels are typically used when the openings are extensive, such as a patio or bi-fold door, and for heavy loads. The steel lintel contains a rolled steel joists or channel sections.


The reinforced cement concrete lintel has many benefits, such as fire-resistant, easy to construct, rigid and high-strength, making them a popular choice for door openings for any span and all loads.

What Size Lintel Do You Need For A Door

It’s critical to get the required door lintel size correct. Therefore, if you’re unsure in any way on how to calculate the lintel size, we strongly recommend you seek help from a professional.

To calculate the door lintel size, you need to know the support load required by your lintel, the construction of the wall, and your lintel length.

Knowing the construction of your wall allows you to work out where the load-bearing points are. Either side of your lintel must be supported sufficiently to ensure the above load is distributed on both sides evenly.

Your lintel will typically sit across the inner and outer leaves of the cavity wall. With a solid wall, the lintel will rest on the single leaf.

With your structural opening known, you can calculate how long your door lintel needs to be. For a door lintel under 1 metre, the door openings lintel size is worked out by measuring the size of the structure opening then adding 10 cm. For lintels over 1 m add 15 cm. This calculation ensures you have a suitable overlap of the door lintel to ensure spreading the load.

We are now determining the load that the door lintel will bear, including cement, floor and roof loads and the general day-to-day building loads. To help calculate this, refer to the lintel load span tables.

These calculations need to be carried out accurately, and if there is any doubt, we strongly advise you to seek help from a professional.

How Do You Install A Door Lintel

Installing the door lintel is a specialised job and should only be carried out by an expert, as carrying out a poor job can have damaging consequences.

The 1st critical step is to fit temporary support to keep the property and brickwork secure and safe while creating the door opening. Steel props, or across, with boy attachments at the top provide good support. Ensure the flooring is solid and sturdy enough to take the load of the steel props. To help distribute the weight, sit the props on a solid, sturdy plank of wood.

To fit the strong boys in position, remove the cement into the rows of bricks using an angle grinder equipped with a diamond-tipped disc or a masonry drill. Slide the strong boys through the gap that you’ve just created, but make sure they are not more than 2.5 feet apart from each other. Your brickwork is now safely supported.

You can now remove the bricks to add the door lintel. Using an angle grinder or a masonry drill, remove the cement around the bricks that have to be taken out. Once the cement has been removed, you can knock the bricks out using a bolster chisel with a heavy hammer.

The next stage is fitting the door lintel. To do this, add a bed of cement onto the main bearing points, then position the lintel in place. Ensure your lintel is level before adding more cement to the lintel top. Leave to dry for a minimum of 24 hours or longer if possible.

When the cement has thoroughly dried, you’ve now installed the door lintel. The support props can be removed, and you can start removing the other bricks to create your door opening.

How Do You Replace A Door Lintel

If this is the first time you’ve replaced the door lintel, we strongly recommend seeking advice from a professional who has experience in this task.

This process of replacing a door lintel is very similar to the steps we took to install a door lintel.

The 1st step is to add your support props and strong boys to support the brickwork above the door lintel.

The next stage is to remove the cement between the bricks directly above the lintel. This will enable you to insert your strong boys into the wall and connect to your support props. As with the door lintel installation, make sure that your floor is stable and secure and that it can take the load. If need be, use a plank to suitably distribute the weight.

Now that your support is in situ, you can cut out the cement using an angle grinder or a masonry drill to remove the bricks around the door lintel. Ensure the area is clear from the old cement to give you a clean space.

Now that your bricks have been removed, you can now change your door lintel. Once the new door lintel is in place, add fresh cement to the bearing points and position your lintel in place, ensuring its level.

Replace the bricks with fresh cement around the lintel and ensure the whole installation is in place and secure. Leave the entire structure to dry for at least 24 hours, or more if possible.

As soon as the cement is dry, you can remove the support props and strong boys. Fill the removed cement where the strong boys were fitted into the wall, and that’s the job done.

Our Final Thoughts

While fitting a door lintel is a job that you can do yourself, it is a job that requires a lot of expertise, accurate calculations and experience and a complete understanding of what the job entails.

If you doubt how to proceed, we strongly recommend you seek help from a building expert with experience installing a door lintel and fitting doors to your home.

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