Adding a storey
to your house.

The most common case is a constrained plot: a small site, footprint already used, setbacks required by the PLU that prevent extending towards the boundaries. Adding a storey uses no land and does not affect footprint rules.

Second case: planning rules block an extension. The ground coverage ratio has been reached, the area limits sprawl, or ground-level buildability is restricted. Going vertical is then the only direction available — provided the maximum permitted height allows it.

Third, more personal case: you don't want to sacrifice the garden. A single-storey extension takes away terrace space and ground-floor light, and often the best-oriented part of the plot. Adding a storey leaves all that intact — and offers views as a bonus, which is no small thing in Savoie.

Adding a storey places a permanent load on a building that was not necessarily designed to take it. Three elements must be checked first: the existing foundations, load-bearing walls and floors.

On a recent concrete-block or concrete building, the margin is often sufficient. On older stone buildings, very common in Savoie, the answer cannot be guessed: foundations are sometimes shallow, masonry uneven, and the real condition only becomes clear after investigative surveys. This study is not an administrative formality — it determines whether the project is feasible at all, and sometimes its final cost.

That is why we carry out this assessment before pricing, not the other way round. A quote for adding a storey drawn up without a structural study commits no one, and is always revised in the wrong direction.

When adding a storey, weight is not a detail: it is the main constraint. A timber-frame structure weighs a fraction of equivalent masonry, which reduces the load transferred to the existing walls and foundations accordingly. In many cases, this is what makes the project feasible where concrete would have ruled it out.

It brings two other advantages on this type of project. Prefabrication in the workshop greatly shortens the time the house is left open — a decisive point when you are still living there. And timber frame builds the insulation into the thickness of the wall, giving good thermal performance without extra thickness.

It is not a universal answer: the choice depends on the existing structure, the architecture, the PLU and the budget. But when adding a storey in Savoie, it is very often the solution that makes the most technical sense.

Your town's local plan (PLU) sets a maximum height. It is the first document to consult, even before the structural study: if the permitted height does not allow the extra floor, the project stops there. It also governs appearance — roof pitch, materials, colours — and the new storey must remain consistent with the existing building and the neighbourhood.

Adding a storey creates floor area and changes the external appearance: a building permit is therefore required in the vast majority of cases. And as with loft conversions, using an architect registered with the Ordre des architectes becomes mandatory above 150 m² of total floor area after the work — a threshold that adding a storey almost always crosses.

We handle reading the PLU, the feasibility study, preparing the permit and following its processing, then coordination of the trades through to handover — under a project management contract or as general contractor with a committed price and timescale.