Building conversion and change of use in Geneva
Planning building work? Apartment, house or building renovation, a new storey or a roof extension, running the project is our job.
Converting a building or changing its use in Geneva means obtaining a building permit, then running a site inside an existing structure. HMG Construction Management SA draws up the plans, files the application as an agent registered on the Geneva MPQ list (mandataires professionnellement qualifiés, the cantonal register of qualified building professionals), works out the cost, appoints the contractors and manages the works to SIA standards until the building is handed over.
How do you get your building conversion done without the worry? By handing the management and the coordination of the contractors to HMG. HMG is there for you.
What counts as a conversion or a change of use?
Converting a building means altering its layout, its structure or its services without demolishing it. Changing its use means giving it another purpose, for example turning a workshop into offices, a storeroom into a shop or offices into a medical practice. The two often go together, because a new use places different demands on the building.
Those demands concern fire safety, escape routes, ventilation, acoustics, access for people with reduced mobility and the load the floors can carry. The first step is therefore to compare what the building offers with what the future use requires. That comparison tells you whether the project is realistic before you commit to significant design fees.
Which building permit do you apply for in Geneva?
In Geneva, building permits are issued by the Office des autorisations de construire (OAC), the cantonal building permit office. The official page on permit types (in French) states that the fast-track procedure, called APA, covers interior changes to an existing building and works that do not alter its general appearance. A project outside that scope follows the ordinary procedure, a full application called DD (demande définitive).
Where the future use raises a question of principle, a preliminary application, called DP (demande préalable), is worth filing. It obtains the authorities' position on siting, use, envelope, volume and access before the detailed design begins. If the building contains housing, the LDTR, the Geneva law on demolition, conversion and renovation of housing, governs the works that affect those homes, and this point is checked first.
According to the page Je prépare ma demande d'autorisation de construire, an application under the ordinary procedure must, with rare exceptions, be filed by a professional on the MPQ list. The Canton also recommends a geo-analysis of the constraints of the plot before filing, which is done online on AC-Démat. Before any interior demolition, the Canton of Geneva page Rénover, transformer ou démolir sans danger deals with the asbestos, PCB and lead to look for in the building. Our guide to building permits and procedures in Geneva presents each procedure.
Who do you call first?
Two routes lead to the same result.
- HMG runs the whole project. The firm studies the feasibility, draws up the plans, files the permit application, prices the works, appoints the contractors and manages the site to completion.
- Your architect designs the conversion and obtains the permit. HMG then takes over the construction phase and works with the architect through to acceptance.
In a conversion, the budget depends heavily on what the existing building reveals. Whichever route you choose, it is wise to bring the person who prices and the person who designs together early.
How HMG manages the conversion of your building
HMG starts with a measured survey of the building and with opening-up at the places that matter, namely the floor slabs, the load-bearing walls and the service shafts. These checks reduce the unknowns before tendering. The firm then coordinates the structural engineer and the building services engineers, and prepares an estimate by trade that separates the certain works from the contingency for the unforeseen.
The contractors are consulted on a common specification and their bids are compared item by item. During the works, HMG chairs the site meetings, writes the minutes, checks the workmanship against SIA standards and verifies invoices before payment. When part of the building stays in use, the schedule separates the areas under construction from the areas in service, with distinct access routes and working hours agreed with the occupants.
Usual steps and timing
- Survey of the building, opening-up and comparison with the requirements of the new use.
- Feasibility study, sketch design and first cost estimate.
- Choice of procedure, plans and permit application.
- Survey of hazardous substances, tenders and contracts with the contractors.
- Interior demolition, structural strengthening, building services, partitions, then finishes.
- Inspections, acceptance of the works, snagging and final account.
The review of the application and the true condition of the structure have the greatest effect on the timetable. HMG draws up a schedule that separates design, permit and construction, then revises it after each discovery made on site.
HMG projects on existing buildings
Frequently asked questions
Do I need a permit to change the use of premises in Geneva?
A change of use affects the purpose of the building, one of the points on which the authorities give their position in a preliminary application (DP). HMG checks which procedure applies to your case with the Office des autorisations de construire, then prepares and files the application.
Can a building be converted while it stays occupied?
Yes, provided the site is prepared in phases. The areas under construction are sealed off from the rest by temporary partitions, water and power shut-offs are announced, and noisy work is scheduled at times agreed with the occupants.
How much does a building conversion cost in Geneva?
The cost depends on the condition of the structure, the services to be replaced and the requirements of the new use. A first estimate is prepared after the survey and the opening-up, then a budget is fixed on the basis of the contractors' bids.
What is the difference between renovating and converting?
A renovation restores what exists without changing the layout or the use. A conversion alters the layout, the structure or the purpose of the building. The second generally needs more design work, and the permit procedure is checked case by case.
Related guides and pages
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