Bolken: observed built density
Municipality in the canton of Solothurn · FSO no. 2514 · Parcel data as of July 2025
- Parcels
- 362
< 1 % of the canton
- Municipal zones
- 12
- Median utilization
- 65 %
Canton: 29 %
Switzerland: 10 %
- Median GFZ
- 0.22
Canton: 0.10
Switzerland: 0.09
- Median height
- 8.6 m
Canton: 9.2 m
Switzerland: 9.5 m
- Median floors
- 2.1
Canton: 2.2
Switzerland: 2.3
About Bolken
Bolken is a municipality in the canton of Solothurn. The parcel data lists 362 parcels in 12 municipal zone types. The zone types with the most parcels are Wohnzone, 2-geschossig (171), Landwirtschaftszone (95) and Verkehrsfläche Strasse (35).
The median parcel is built to a volume utilization of 65 %; half of the parcels lie between 6 % and 103 %. The canton median is 29 %, so Bolken sits above it.
The median building height is 8.6 m at 2.1 floors, and the median floor-area ratio (GFZ) is 0.22. Parcels built in the last 20 years reach a mean volume utilization of 103 % (57 parcels), higher than the 60 % across all building years.
Parcels by municipal zone
| Zone | Parcels | Median utilization |
|---|---|---|
| Wohnzone, 2-geschossig | 171 | 94 % |
| Landwirtschaftszone | 95 | 0 % |
| Verkehrsfläche Strasse | 35 | 0 % |
| Kernzone | 14 | 81 % |
| Verkehrszone Strasse | 13 | 0 % |
| Wohnzone, 3-geschossig | 11 | 88 % |
| Wald | 8 | 0 % |
| Erhaltungszone | 6 | 81 % |
| Gewässer | 4 | 0 % |
| Zone für öffentliche Bauten und Anlagen | 3 | 10 % |
| Naturschutzzone Tümpel Turbenmoos | 1 | 0 % |
| Verkehrsfläche Bahnareal | 1 | 0 % |
Volume utilization (ratioV)
Of the 353 parcels with a value, half lie between 6 % and 103 %. The median is 65 % and the mean 58 %.
Share of parcels by range
- below 50 %45 %
- 50 % to below 100 %28 %
- 100 % to below 150 %21 %
- 150 % and above5 %
Floor-area ratio (GFZ)
Of the 353 parcels with a value, half lie between 0.06 and 0.38. The median is 0.22 and the mean 0.21.
Share of parcels by range
- below 0.5093 %
- 0.50 to below 1.007 %
- 1.00 to below 1.500 %
- 1.50 and above0 %
Building height
Of the 206 parcels with a value, half lie between 7.4 m and 9.6 m. The median is 8.6 m and the mean 8.6 m.
Share of parcels by range
- below 8 m33 %
- 8 m to below 12 m62 %
- 12 m to below 20 m4 %
- 20 m and above0 %
Number of floors
Of the 158 parcels with a value, half lie between 1.7 and 2.5. The median is 2.1 and the mean 2.1.
Share of parcels by range
- below 212 %
- 2 to below 366 %
- 3 to below 522 %
- 5 and above0 %
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 | 362 | 60 % |
| Last 60 years | 183 | 101 % |
| Last 40 years | 146 | 105 % |
| Last 20 years | 57 | 103 % |
| Last 15 years | 45 | 104 % |
| Last 10 years | 22 | 110 % |
| Last 5 years | 10 | 100 % |
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).