In this section
French Building Regulations: One National Code
France runs one national Code de la construction et de l'habitation, backed by arrêtés and the private NF DTU technical standards — but a lot of the numbers people expect (stair rise, ramp gradient) actually come from the *accessibility* rules, which by law don't apply to a house you build for your own occupation. This hub separates what's genuinely mandatory for a private self-build from what only applies to housing built for sale or rent.
Rules by topic
The parts of the code a chippie actually sets out — each one in plain English, with the numbers and a calculator.
Footings & slabs
One code for the whole country
France has one national Code de la construction et de l’habitation (CCH), and it applies the length and breadth of the country — no département-by-département or commune version. The CCH sets out the legal requirements; the detail underneath it is spread across décrets, arrêtés (ministerial orders) and, for a lot of the practical execution detail, the private NF DTU technical standards published by AFNOR.
The exemption most guides skip
Here’s the thing a lot of secondary sources get wrong, and this hub tries hard to get right: a large share of the quantified stair, guard-opening and ramp figures people cite as “French building code” don’t actually come from a general building code at all. They come from the accessibility regulations (the arrêté du 1er août 2006 and the arrêté du 24 décembre 2015), and those regulations, by law, exempt an individual house built by or for its own owner-occupant (CCH art. L111-7-1 / R.111-18-4). They apply in full to a house built for sale or rent, and to collective buildings and ERP (public-facing establishments) — just not to your own self-build.
So on these pages, wherever a “code number” only exists in that accessibility scope, we say so plainly and don’t print it as if it were a mandatory rule for a private house. Where there genuinely is no fixed dwelling figure — private stair rise and going is the clearest example — we say that too, and explain what actually governs instead: trade convention (the loi de Blondel), the one CCH clause that is general (guard-corps height), and the NF DTU standards a builder works to on site even though they’re not, strictly, “the law.”
Where the numbers that ARE mandatory come from
A handful of figures genuinely do apply to every dwelling, self-build included, and this hub carries them straight: the guard-corps height at a balcony, terrace or floor edge (CCH art. R134-59), the minimum ceiling height / room size used as the practical décence (habitability) floor (Décret n°2002-120), and the ventilation flow-rate table (arrêté du 24 mars 1982) — the one genuinely hard, table-driven number in the whole cluster.
One more thing worth knowing before you rely on any figure here: CCH Book I was recodified wholesale on 1 July 2021, and a lot of familiar article numbers changed (the guard-corps rule, for instance, moved from the old R111-15 to the current R134-59). Any pre-2021 citation you find elsewhere should be treated as potentially superseded. Always confirm the current text on legifrance.gouv.fr before you sign off on a job.