Sannois · report
Renovation in Sannois
In 2025, 33% of the homes authorised were in existing buildings: conversions, extensions and changes of use.
- Homes in existing buildings, 2025
- 33%
Homes authorised in Sannois: new buildings and existing ones
Dwellings authorised each year, by the year the permit was granted: in new buildings, and by works on existing buildings (conversions, extensions, changes of use). SDES Sitadel.
- Existing buildings
- New buildings
Show the numbers
| Year | New buildings | Existing buildings | Total |
|---|---|---|---|
| 2025 | 8 | 4 | 12 |
| 2024 | 39 | 4 | 43 |
| 2023 | 326 | 4 | 330 |
| 2022 | 156 | 18 | 174 |
| 2021 | 484 | 8 | 492 |
| 2020 | 12 | 4 | 16 |
| 2019 | 69 | 34 | 103 |
| 2018 | 243 | 5 | 248 |
| 2017 | 658 | 81 | 739 |
| 2016 | 249 | — | 249 |
| 2015 | 130 | 1 | 131 |
| 2014 | 10 | 1 | 11 |
| 2013 | 154 | — | 154 |
Only permits that create dwellings are listed, so renovation that adds no home (refurbishing, insulating, re-roofing) is not counted. A permit is permission to build, not a finished home. The current year is left out until it is complete.
Other reports for Sannois
At the median sale price, a 90 m² home costs €330,030. With 10% down and a 30-year mortgage, the payment is €1,285 a month. The HCSF caps it at 35% of a household's income.
- Payment, two incomes
- 28%
- Payment, one income
- 56%
Owning a 90 m² apartment costs less each month than renting it. Owning counts interest, running costs and the return the deposit could earn, at apartments' median sale price; rent is the asking rent. Repaying the loan is saving, so it is left out.
- Rent per month
- €1,784
- Owning per month
- €1,095
Figures for Val-d'Oise: Sannois has no reliable figures of its own.
32.3% fewer homes were licensed for construction in the last 12 months than in an average year of the past decade.
- Licensed, 12 months
- 4,869
In 2022 the population grew by 152 while 184 homes were started: 0.8 new residents for every new home.
- New residents per new home, 2022
- 0.8
- Population change, 2022
- +152
5.1% of the 12,193 homes counted in the 2023 census stood empty, whether for sale, to let or for other reasons.
- Empty, 2023 census
- 5.1%
- Empty homes
- 618