Screening Methodology of Natural Hazards for Buildings

4. Overview: Most relevant risks for GVB

6. Methodology to estimate risk values: flooding r: risk value f j : frequency of scenario j (per year) D j : damage (CHF) V: insurance value (CHF) d j : relative damage j: scenario (characterised by frequency class)

8. Methodology to estimate risk values: flooding d j : relative damage  : maximal probable loss in relation to the insurance value s: damage sensitivity (vulnerability): average damage without protection measures as a percentage of the maximal probable loss f: effect of safety measures reducing the damage i: index of building j: scenario (characterised by 1 out of 3 frequency classes)

9. Methodology to estimate risk values: flooding How to estimate the different variables :  : maximal probable loss per insurance value - local estimate (upon inspection, e.g. maximum 2 of 4 similar storeys affected due to static high water  0.5 ) s: damage sensitivity: - fixed basic values depending on event intensity - factors depending on sensitivity of materials used on floors + walls towards moisture, existence of critical installations in ground floor (e.g. electric equipment) f: effect of safety measures reducing the damage - standard values for measures such as protection dam or height of lowest opening

10. Calibration of parameters Total and average risk values should be consistent with experience 3.050 176 9.000.000 Windstorm 6.199 176 9.000.000 Hailstorm 16.370 586 30.000.000 Flooding Average damage per event to a building [CHF / year] Risk value for an average building [CHF / year] Average overall risk value [CHF / year] Hazard type