Do you dream of a more spacious house without having to move? This is possible with raising, a technique of creating additional surface on the roof without encroaching on the ground. A good alternative to create a new room without major work. What are the stages of this type of extension? To find out, asked the architect Joël Van Nieuwenhuyse from the Daligaux-Van Nieuwenhuyse cabinet, who will give you his advice on the subject.
: What are the conditions necessary to raise your roof?
Joël Van Nieuwenhuyse: In theory, anyone can raise their roof. However, there is a study to be done on the structure of the building to see if it can support an additional load. To increase the chances, we work in this case in wooden frame because it minimizes the weight and the load on the existing structure. On the financial level, the costs vary according to the type of elevation, the structure and the modifications of the ground floor. To give you an idea, whether it is an extension or an extension, the cost per square meter is around 2000-2500 €.
: What are the stages of construction of an elevation? How long does the site last?
Joël Van Nieuwenhuyse: The work begins with the removal of the elements of the existing house: the roof, the frame and the modification of the floor between the ground floor and the first floor. There are 2 ways to do this: walls can be prefabricated and installed more quickly on site. It depends on accessibility to the site. If it is accessible with hoists, the panels are important. On the other hand, if it is in an urban environment such as in the city center where access to vehicles is difficult, the walls are portable and therefore smaller. The workers mount them as they go upstairs under construction. The deadline depends on the scope of the project. For example, for an extension of 15m² upstairs on a structure of the same surface, the work takes around four months.
: What materials are used to add a floor to your home?
Joël Van Nieuwenhuyse: 90% of the wood frame is used. This allows a site to be faster, dry and ecological. The façade is clad in natural wood or fiber cement panels, a mixture of cellulose, sand and cement. For the cover, zinc is used.
: What are the legal rules to follow for an elevation?
Joël Van Nieuwenhuyse: For any extension greater than 20m², the town hall's approval is required with a building permit. The local urban plan (PLU) fixes the maximum height of the buildings. If you are considering an extension of 50m² or more, I know that you will have additional calculations to include in your building permit file. Below this surface, the file is simplified.
: Are there any precautions to take towards the neighborhood?
Joël Van Nieuwenhuyse: If you are on the edge of property and the building permit authorizes it, you have no authorization to do so. But you should know that some municipalities impose a neighborhood agreement.
: Can an individual carry out the roof raising work himself?
Joël Van Nieuwenhuyse: At the level of the design of the building permit, if you exceed 170 m², you have to make the plan and design with an architect. Touching the structure of the building and its waterproofness involves risks because the individual has no insurance in the event of a disaster. An alternative is then possible if he wants to be a handyman: he calls on an architect to produce the exterior envelope and he takes care of the interior design (insulation, installation of Placo® and floor-paint coating ).
For more info: www.dvn-architectes.com