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Extension work on a house:what approach? what cost?

Extension work on a house:what approach? what cost?

Enlarging a house means creating more space or adding a few square meters to its initial surface. The reasons that lead to a house extension can be many, such as the arrival of a new member in the family or simply for comfort.

To make the extension, there are different ways, it depends mainly on the state of the house. Using the elevation of the house, for example, to add an extra floor is one option, just as the creation of new rooms is another. What is the procedure to follow and what is the cost for the extension work of a house?

Approach for the extension work of a house

First of all, it is necessary to learn about the legal procedures regarding the different types of extensions. Some require building permits and others only require a simple prior declaration of work. In addition, the formalities are different depending on the size of the extension work to be carried out.

A building permit is required for extensions with a floor area greater than 20 m2, and greater than 40 m2 in urban areas and for a total living area of ​​approximately 170 m2.

A prior declaration is to be made for an extension in the following cases:a floor area greater than 5 m2, less than 40 m2 and a total surface area of ​​the dwelling of 170 m2, in an urban area. It is therefore necessary to obtain authorization from the administration to avoid possible and future legal problems.

An extension project requires the services of a professional, because it is not just work that can be done by an amateur.

Prices of different types of home extensions

Extension work on a house:what approach? what cost?

The price of a home extension depends on the type of work to be done. Regarding the raised extension, this operation consists of raising the house to add one or more additional floors. This is the ideal option when you have a limited floor space. During the works, reinforcement of the foundations is mandatory. For example, for an elevation with development and roof extension, the price will be between 900 and 2000 € per m², but this varies according to the work to be carried out.

The development of the attic:this option is chosen when the structure of the house has a space which is not exploited and which can be converted into another additional room. The price for a redevelopment varies between 500 and 1500 € per m².

The side house extension and the veranda are also solutions to gain more volume. The price for a veranda is calculated according to the material chosen, it varies from 500 to 2500 € per m². For example, the m² for a house extension in glass or steel for a veranda amounts to 2000 €. If it is a wooden veranda, the price is around 1000 € per m².

Future costs also include property taxes and expenses related to supplying the new space with electricity, heating and, possibly, water.