Climate change impact on buildings and constructions
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Climate change impact on buildings and constructions

Buildings and roads etc. must be designed for future climate conditions.
Wetter winters and sudden, heavy downpours make it even more important to direct rainwater and meltwater away from houses, paved areas, roads etc.

A milder climate will reduce the durability of building materials and affect the indoor climate of buildings. Warmer summers will introduce a greater need for cooling.

Higher groundwater levels, higher water levels in streams and watercourses, and greater risk of storm surges along the coastline, make it pertinent to safeguard buildings against seepage and flooding.

Buildings can be vulnerable to climate change. In the future there may be an increase in the risk of collapse, declining health and significant loss of value as a result of more storms, snow or subsidence damage, water encroachment, deteriorating indoor climate and reduced building lifetime. In the short term stronger storms are the greatest challenge. 

Storms will constitute a safety risk in those parts of existing buildings that do not meet the building code's safety requirements. In the longer term, more and longer-lasting heat waves could have health-related consequences, especially for the elderly and weak, in nursing homes, for example.

Adapting buildings to climate change
Adaptation in Denmark may be  with regard to limiting snow-load and storm damage as well as controlling indoor climate in particular. With respect to strengthening existing buildings, however, autonomous adaptation will be limited if owners are not familiar with weaknesses in the bearing elements of their buildings. Adaptation will only occur in new constructions if standards are enhanced. As for counteracting consequences of heat waves, installation of air conditioning in existing buildings could be expected, along with a demand for buildings with more efficient indoor climate control.

In Denmark, it is the responsibility of individual building owners to see that applicable regulations are complied with, and it is also they who will seek solutions for satisfactory indoor climate. I n the short term there will be no  changes in the laws pertaining to building safety under extreme weather conditions. For countering heat waves, the new regulations regarding the energy framework in the building code represent a step towards promoting solar screening and heat-deflecting windows, which will make it easier to regulate indoor climate.

For the time being, no  measures are recommended for building extensions or renovation.

In the future, there may be a need to inform owners of existing buildings of the typical weaknesses in the bearing elements, with corresponding instructions on how to remedy them. In the same manner, there may be a need for instructions on new building solutions to reduce indoor temperature extremes during heat waves, especially for vulnerable buildings. Finally, there may be a need to inform construction technicians of recommended future-oriented design parameters, for example, concerning maximum snow load and wind speed, temperatures and durations of future heat waves and the maximum precipitation intensity a building should withstand.

The roads of the future

New roads must be designed in accordance with future requirements. Investigations have therefore been launched to clarify how to update current guidelines for planning, constructing and managing roads.

Rain the biggest risk factor
For existing roads, the risk of more rain poses the greatest challenge. Surface water must be directed away from roads in order to ensure their durability, avoid aquaplaning and reduced pass ability for road users. Danish road authorities are therefore currently looking at how road drainage systems may be adapted to future climate, both with regard to new construction and when managing existing infrastructure.

Traffic reports during extreme weather events
During extreme weather events such as heavy downpours, storms etc., traffic reports play a central role for road users. They can continuously receive fresh traffic and weather reports,  e.g. via the radio, mobile phone, or GPS, as well as via traffic management systems.

Research in roads and climate
Both in Denmark and internationally, research is being carried out into roads and the climate. This research provides new knowledge to road authorities on how to best carry out future construction and management of Danish roads, vis-à-vis the consequences of climate change for society.

Adapting railways to climate change
Powerful storms and increased wind speeds could have financial and traffic-related consequences for electric railways, e.g. because overhead wires are vulnerable to higher wind speeds.

An increase in the groundwater level could lead to increased risk of erosion of railway cuttings. Heavier showers could pose problems for the railway drainage system, and the risk of erosion could become greater where watercourses intersect the railway line.

Rail Net Denmark's adaptation to climate change
Rail Net Denmark, which manages the Danish railway infrastructure, is preparing for how to cope with greater volumes of precipitation, including especially heavy downpours. Rail Net Denmark has already implemented routines for intensified inspection and control of problematic embankments and dikes in the event of continuous large volumes of rain, and is also securing well-functioning drainage systems for ditches along the railway.

Rail Net Denmark is also investigating drainage systems at railway stations.  Focus is on railway stations where drainage problems have been observed which e.g. have caused unintended track movement.

Furthermore, Rail Net Denmark is establishing a cooling plant that is to protect the interlocking system against increases in temperature, and they are felling and trimming trees to reduce the risk of falling trees.

Early warning system
To prevent accidents on the railway following heavy downpours, Rail Net Denmark has introduced a new early warning procedure which can shut down the train service in the event of problems. 

Bridges and tunnels
The construction of the two large Danish bridges, the Great Belt bridge and the Oresund bridge, took into account future climate change.  

The bridges and their shore-based installations are directly exposed during events with high water levels. The shore-based installations are therefore protected by dykes. However, the accessibility of these installations could be affected by more frequent storms.

Railway traffic across the Great Belt is via a tunnel, and the link across Oresund also includes a tunnel, just as its shore-based installation is below sea level. The tunnels are therefore vulnerable to rising sea levels.

Continuous control of dykes
Dykes protect the installations against water impacts. There is ongoing control of the state of the dykes. This control is carried out as annual routine inspections and as inspections after events such as storms, extreme water levels, ice winters etc. 

Regular risk analyses
Regular risk analyses are carried, mapping future risks of flooding of installations on the basis of developments seen in the previous five to ten years.

Increasing water levels due to climate change will happen over a period of many years, but as the installations are also expected to have long-term durability, constant focus is on appropriate and adequate dyke protection and efficient emergency measures in the event of extreme weather.