Properly enlarging your house: 6 mistakes not to make

Enlarging your house is a project that allows you to preserve your home by adapting it to your new needs. Whether to welcome a new member of the family, set up a work space, or simply increase the value of your property, the reasons for extending your home are many and varied.

But house extension projects, like all construction, must be well thought out. Because some mistakes can be costly. Maisons SIC, specialist in house renovation and extensions of all kinds, gives you the keys to answer 5 of the main mistakes to avoid.

• Not being accompanied by the right partner to enlarge your house

Expanding your house costs money and has long-term consequences. A manufacturer with many years of experience will be able to answer all your questions precisely because he will have faced different situations. The complexity of expansion work requires expertise that only experienced professionals can offer. More than 50 years of expertise Maisons SIC in the construction of individual houses can make a real difference here.

Managing building permits, respecting local standards, and optimizing spaces are all essential skills that a good partner can bring to your project.

Especially since the question of materials is essential in the construction of a house extension. Concrete, concrete block, single-wall bricks, wood, aluminum, glazing, wrought iron, steel, PVC, fiber cement panels, natural or reconstituted stone, and plaster. Each building material has its specificities, its advantages and disadvantages. And only a building professional can enlighten you on the subject.

Another advantage of calling on an experienced builder to enlarge your house: perfect mastery of current standards, in particular those of RT 2012 / RE 2020. Indeed, for any extension of your house exceeding 150 m² or corresponding to more than 30% of the existing surface area, certain criteria must be applied, such as the heating consumption of an individual house must not exceed 12 kWh/m² per year.

A professional will also be able to help you with all purely technical aspects such as the soil study, stability issues, foundations, waterproofing between two frames and work on orientation and layout.

Also read: House extension: the 11 key steps

• Predict the environmental impact of the expansion

Before embarking on an expansion project, it is crucial to consider the environmental impact of your extension. Using sustainable materials and eco-friendly construction techniques can not only reduce your carbon footprint but also improve the energy efficiency of your home.

Incorporating eco-friendly solutions such as solar panels, rainwater harvesting systems, and reinforced thermal insulation can help make your extension more sustainable and energy efficient. In particular, choose to enlarge in wood can be an excellent option for those looking to combine aesthetics, durability, and respect for the environment.

• Expand your house without thinking about permissions and neighbors

There are many mandatory and legal authorizations that should be requested before starting to think about extending your house. Ignoring these steps can lead to legal complications and fines, or even demolition of the extension.

First of all, find out about local regulations. Your town hall can provide you with information on the town planning rules in your area (height of buildings, materials used on facades, etc.).

The first administrative step to take is to declare your work at the town hall, to obtain the famous prior declaration of work. It only concerns extensions whose living area is between 5 and 40 m², which can be located in an urban area covered by a Local Urban Plan (PLU). A stage which concerns both L-shaped constructions and extensions using materials such as wood.

If your project to enlarge your house exceeds 40 m² of living space, or if the entire house reaches or exceeds 170 m² Net Gross Surface Area (SHON), you will need to request a building permit becomes mandatory. For houses reaching this last surface area, the law also requires the intervention of an architect.

Once your extension has been built, you will have to complete a Declaration of Completion and Conformity of Works (DAACT). But also get a certificate of non-contestation from the town planning services within three months following the end of the work.

Please note, these steps are anything but optional! In case of non-compliance (with a limitation period of up to six years for criminal liability and ten years for civil liability), you risk the demolition of the non-compliant extension.

To help you find out correctly about the administrative conditions for extending your house, consult a building professional such as Maisons SIC !

 

Also read: Understanding the administrative procedures for a house extension

 

Why is it crucial not to forget to warn the neighbors?

Well before starting your house extension project, it is essential to inform your neighbors for several reasons.

First of all, for compliance with town planning rules : for example, buildings must be erected at a minimum distance of 3 meters from the neighboring property, according to the town planning code. Informing your neighbors allows you to check compliance with these standards together and avoid possible violations.

Then, it is certain that your work will generate noise and visual nuisance. Notifying your neighbors is therefore a simple sign of courtesy allowing you to maintain good neighborly relations and to mitigate the possible negative impacts of this work to enlarge your house.

Communicating clearly about your construction intentions is not only a question of legality, but also of good neighborliness. This makes work easier and ensures a harmonious living environment for everyone.

 

• Not thinking about the exact function of the new room in your house

Have you found your partner for the creation of your extension? But before you decide on the type of house extension you want, you need to ask yourself what the function of this room will be.

If you wish to start or continue a teleworking activity, this room will be an office. It will then necessarily have to be bright but not too bright (especially if you are working on a computer). It will also need to be well insulated. A veranda with a large glazed area is, for example, less recommended here than a brick extension or an attic conversion.

You are going to welcome a child or an elderly person of your family within your home? Here you need a room that is well insulated thermally but also soundly. The extension in concrete or concrete block or the conversion of the attic could be a good idea but you have to think about the adjacent room: it is better that it is a kitchen than a living room or a bathroom...

You just want an extra living room. If you don't need light, the basement layout can make a laundry room, a games room, a cinema room or a storage space. If you want to see your beautiful garden, a veranda or a wooden extension with large bay windows can be good solutions too.

• Do not analyze upstream the different house extension solutions

So you have defined your need to extend your home: an extra room to set up an office in your home, for a child's bedroom or to accommodate a member of your family? Expanding your house offers many possibilities. And before you decide, it is important to know all the choices available to you. Because each has its advantages, its cost and its disadvantages.

 

1. Concrete or concrete block expansion

• Advantages: This method is economical and offers a very solid structure.
• Disadvantages: The design may lack aesthetics and may not blend in harmoniously with the rest of the house.

 

2. Wooden extension

• Advantages: Wood is aesthetic, authentic, durable and offers good insulation. It adds a natural charm to the property.
• Disadvantages: This option may be more expensive due to materials and specialized construction.

 

3. Installation of a veranda

• Advantages: Perfect for taking advantage of natural light and offers a feeling of openness to the outside. Ideal for a winter garden or relaxation room.
• Disadvantages: May require regular maintenance, especially if the structure includes a lot of glass.

 

4. Expansion/creation of garage / carport

• Pros: Converting a garage is a great way to add an extra room without sacrificing outdoor space.
• Disadvantages: The conversion must be well insulated and ventilated to be comfortable, which may incur additional costs.

 

5. Arrangement of the attic

• Benefits: Maximizes living space without changing the footprint or facade of your home.
• Disadvantages: Requires good insulation and may involve structural costs if the roof needs to be reinforced.

 

6. Layout of the basement

• Advantages: Ideal for adding an extra room such as an office or a games room.
• Disadvantages: Lack of natural light and may require significant work for insulation and waterproofing.

 

Each option for expanding your house therefore has its specificities. Your constructor Maisons SIC will guide you towards the best choice!

 

• Expand your house without considering harmony with the existing and the environment

When you have decided to extend your house and have chosen the most appropriate extension, it is also important that it fits perfectly with the style of the existing building. The whole house + extension must be homogeneous. Ask the architects of Maisons SIC, for example, to help you find the structure that will best match your current home.

At the exterior level, the harmonization of facades is essential. Whether through the choice of materials or through modifications such as resurfacing the existing plaster, every detail counts to ensure a smooth transition between the old and the new.

For example, a wooden extension can complete a stone facade, thus enriching the authentic character of the house while bringing a touch of warmth. Adding large picture windows can also align with local regulations while maximizing natural light.

Inside, the reorganization of spaces must also be considered. If the addition involves a sunroom, it may be appropriate to reconfigure the living areas to create a natural flow to this new space. Likewise, if you are converting an attic, considering easy access to toilets is crucial.

—

To avoid any mistakes when you decide to enlarge your house, do not hesitate, we contact Maisons SIC !