Risks from extreme weather events

Every housing company is unique

Every housing company is unique, so extreme weather events affect them differently. Factors such as the building plot, its elevation differences, any trees, the surrounding urban structure, the building materials and the shape of the building all affect the risks of the housing company.

For example, asphalted or paved building yards have a higher risk of rainwater ponds and flooding. If your building has large south-facing windows and no trees in the yard, there is a high risk of the apartments overheating. If your building has natural ventilation, the apartments are particularly prone to overheating. The function of natural ventilation is based on thermal differences, which do not exist in hot weather.

Main risks are heatwaves and stormwater floodings

The City of Helsinki has estimated that extreme heat and heavy rainfall and the resulting stormwater flooding will be some of the mostsignificantrisks for Helsinkiresidents inthe near future. Read the city report here.

A dense urban structure has a large amount of paved surface area in relation to soil and vegetation that absorb and evaporate water. During heavy rainfall, water from these areas is not absorbed into the soil quickly enough, stretching the capacity of stormwater drains. The housing company is responsible for the absorption and retention of rainwater generated on the plot. The best way to prevent the risk of stormwater flooding is to increase the amount of surface area that absorbs and evaporates water. Read more about housing companies’ stormwater management on the HSY website.

Heatwaves are already having an impact on health and they will only grow longer in the future. As the population ages and heatwaves become more frequent, a growing proportion of the population is in a vulnerable position – and this is true in housing companies too. Find useful tips and information on how to prepare for heatwaves on the HSY Climateinfo website (in Finnish).