Sion: observed built density
Municipality in the canton of Valais · FSO no. 6266 · Parcel data as of July 2025
The parcel data covers only part of the land in the canton of Valais, so figures here may be incomplete.
- Parcels
- 12’358
2 % of the canton
- Municipal zones
- 69
- Median utilization
- 9 %
Canton: 7 %
Switzerland: 10 %
- Median GFZ
- 0.08
Canton: 0.07
Switzerland: 0.09
- Median height
- 9.1 m
Canton: 8.4 m
Switzerland: 9.5 m
- Median floors
- 2.4
Canton: 2.3
Switzerland: 2.3
About Sion
Sion is a municipality in the canton of Valais. The parcel data lists 12’358 parcels in 69 municipal zone types. The zone types with the most parcels are Zone agricole (2’056), Habitat individuel plaine (1’255) and Zone agricole 1 et 2 (1’041).
The median parcel is built to a volume utilization of 9 %; half of the parcels lie between 4 % and 83 %. The canton median is 7 %, so Sion sits above it.
The median building height is 9.1 m at 2.4 floors, and the median floor-area ratio (GFZ) is 0.08. Parcels built in the last 20 years reach a mean volume utilization of 133 % (975 parcels), higher than the 82 % across all building years.
Parcels by municipal zone
| Zone | Parcels | Median utilization |
|---|---|---|
| Zone agricole | 2’056 | 0 % |
| Habitat individuel plaine | 1’255 | 85 % |
| Zone agricole 1 et 2 | 1’041 | 0 % |
| Zone résidentielle H30 | 745 | 47 % |
| Aire forestière | 591 | 0 % |
| Vieille ville | 480 | 99 % |
| Villages-Hameaux | 432 | 0 % |
| Centre III | 428 | 49 % |
| Zone agricole protégée | 329 | 0 % |
| Habitat individuel coteau | 320 | 93 % |
| Habitat individuel coteau sensible Différé | 307 | 43 % |
| Zone d'affectation différée | 289 | 0 % |
| Other zones (56) | 4’085 | - |
Volume utilization (ratioV)
Of the 12’247 parcels with a value, half lie between 4 % and 83 %. The median is 9 % and the mean 72 %.
Share of parcels by range
- below 50 %66 %
- 50 % to below 100 %14 %
- 100 % to below 150 %9 %
- 150 % and above11 %
Floor-area ratio (GFZ)
Of the 12’247 parcels with a value, half lie between 0.04 and 0.41. The median is 0.08 and the mean 0.43.
Share of parcels by range
- below 0.5079 %
- 0.50 to below 1.009 %
- 1.00 to below 1.504 %
- 1.50 and above9 %
Building height
Of the 5’086 parcels with a value, half lie between 7.2 m and 12.2 m. The median is 9.1 m and the mean 10.5 m.
Share of parcels by range
- below 8 m36 %
- 8 m to below 12 m39 %
- 12 m to below 20 m19 %
- 20 m and above6 %
Number of floors
Of the 4’797 parcels with a value, half lie between 1.8 and 3.3. The median is 2.4 and the mean 2.8.
Share of parcels by range
- below 210 %
- 2 to below 344 %
- 3 to below 533 %
- 5 and above13 %
Building age cohorts
Mean volume utilization of the parcels built inside each window, from all years on record down to the last five. The windows overlap: the last 20 years include the last 5.
| Built in | Parcels | Mean utilization |
|---|---|---|
| All years | 12’358 | 82 % |
| Last 60 years | 2’812 | 125 % |
| Last 40 years | 2’026 | 131 % |
| Last 20 years | 975 | 133 % |
| Last 15 years | 684 | 141 % |
| Last 10 years | 372 | 155 % |
| Last 5 years | 148 | 134 % |
How to read this page
room shows observed built density: what has been built on the parcels, not what the zoning permits. Volume utilization (ratioV) compares the built volume of a parcel with the reference volume of its municipal zone type. The floor-area ratio (GFZ) is floor area divided by parcel area; building height and number of floors are taken from the buildings on a parcel. Figures pool all municipal zones of the area. Medians and quartiles are read from bins 10 points (ratioV), 0.1 (GFZ), 2 m (height) and 1 floor wide, so they are exact to within one bin; means are exact. A parcel counts in a distribution only when the parcel data has a value for it. The floors distribution leaves out parcels without a building (0 floors).