Do you want to knock down an internal wall? Here’s what you need to know about costs and important considerations

The demolition of internal walls is an intervention that can completely transform the appearance and functionality of a living space. In this practical guide we will explore the costs, considerations and techniques to take into account to successfully complete this type of work. The demolition of internal walls can open up new design perspectives and improve the liveability of an environment, but it is important to carefully evaluate every detail before starting the work.

Permits required to demolish internal walls

In many cases, it is not necessary to obtain a building permit to knock down interior walls. However, there are exceptions. If your home is a historic building, it will be essential to request a building permit. Additionally, you will likely need to submit a Building Regulations Compliance application. Building Control will carry out an inspection of the work and, if everything complies, issue a certificate.

Building regulations and controls

Normally, compliance with building regulations is required when knocking down internal walls. This is especially true if the walls provide protection in the event of a fire or are structurally load-bearing. Non-load-bearing walls that serve as fire protection or that are located near stairs may also require inspection by building authorities.

Involvement of a structural engineer

To ensure safety when removing load-bearing walls, it is often necessary to involve a structural engineer. These will determine the type of beams or lintels needed to support the structure. This step is essential to obtaining accurate quotes from builders and ensuring the work is carried out safely.

Maintain cleanliness and safety

• Make sure they are installed dust screens to contain debris.
• Consider the costs of moving radiatorsswitches and electrical sockets.
• Include the need for redoing in the estimate plasters and wall decorations.
• Avoid damaging original elements and preserve the zoccoli originals.
• Keep small sections of the original wall to support new beams when necessary.

Agreements with neighbors

If the wall removal involves a wall bordering your neighbor’s property, a partition wall arrangement. Consulting a specialist surveyor ensures that all legal requirements are met. In some cases, it may be necessary to build new supports to support the new beams.

Identification of load-bearing walls

Not all interior walls are load-bearing. However, it is crucial to identify which ones are before proceeding. A qualified structural engineer or builder can help with this assessment to avoid costly and dangerous mistakes.

Procedure for knocking down an internal wall

Here’s how to proceed:

1. Disable wires and pipes inside the wall.
2. Protect rooms from dust using sheets and tape.
3. Remove ceiling plaster to expose beams, wires and pipes.
4. insert temporary supports to support the ceiling.
5. Remove door frames and lintels.
6. Start demolishing the top of the wall slowly.
7. Remove any heavy lintels.
8. Continue demolition down to the ground.
9. Prepare the space to insert the new steel beam.
10. Lift and place the new beam.
11. Reinforce the wall and apply new plaster.

Steel beam boxing

Steel beams must be covered with plasterboard to comply with fire regulations. One option is to build a suspended ceiling to hide the beam. In cases where floors are not at the same level, floor leveling may be necessary for a uniform result.

Costs to demolish an internal wall

Costs vary depending on the specific project. For a load-bearing wall of approximately 5 metres, builders’ estimates range from €1,250 ai €2,500 + VAT. This includes temporary structural support, demolition, installation of new steelwork, fire protection and finishing works. The costs for the structural engineer vary between €300 and €500 + VAT.

Duration of works

Removing an interior wall generally takes less than a week, assuming there are no structural complications. Demolition and beam installation operations can be completed in one or two days; plastering and painting take another couple of days.

Home insurance

Check if your insurance policy covers improvement work. Often, standard policies do not cover major renovation works.