Heat protection must become a construction standard

For many years now, Europe has been experiencing significantly more hot days per year: indoor spaces remain hot for weeks on end and barely cool down even at night. Cardiovascular issues, concentration problems, poor sleep, exhaustion and the resulting drop in productivity have become normal part of summer for many people and businesses. "The dangers posed by heat waves are still underestimated" says Andreas Kraler, Managing Partner of the HELLA Group. “Heat protection is not a question of budget, but of health and social justice. That is why this issue should not be turned into a political football. Federal, state, and local authorities have a responsibility to quickly make public buildings heat-resilient and to effectively protect the population from the consequences of increasingly frequent heat waves." HELLA is therefore calling for a shift in thinking in politics, business, and society: Anyone building or renovating today must plan not only for the winters but also for the summers of tomorrow.

Whether it is a home, office, school, kindergarten, hospital, or care home, the extent to which people suffer from heat depends largely on the quality of the buildings in which they spend their time. Large, unshaded glass surfaces, a lack of external sun protection and inadequately insulated façades and roofs cause interior spaces to heat up drastically and retain that heat for hours. Attics, older existing buildings and modern glass façades are particularly affected. Yet protection against summer heat is primarily a matter of planning. Where buildings are consistently shaded and equipped with effective sun protection solutions, indoor temperatures remain up to 10 degrees Celsius cooler. This not only improves living comfort but also creates healthier workplaces, better learning conditions and a more pleasant environment for children, patients and those in need of care.

High indoor temperatures have a direct impact on health. Poor sleep, exhaustion and difficulty concentrating disrupt the daily lives of many people. At the same time, performance and productivity decline. In offices and workplaces, the strain on employees increases; in schools and preschools, learning becomes more difficult; and hospitals and long-term care facilities must protect particularly vulnerable individuals. Consequently, heat is increasingly becoming an economic and societal risk. A lack of cooling and inadequate sun protection not only cause health issues but also lead to higher rates of sick leave, productivity losses and rising energy costs due to the increased use of air conditioning.

The impact of heat waves affects different segments of the population to varying degrees. Older adults, children, people with chronic illnesses and those with low incomes are particularly at risk. People who live in poorly renovated apartments or work in places without adequate sun protection are often left defenceless against the heat. At the same time, many households cannot afford energy-intensive air conditioning systems or choose to avoid using them due to cost and climate protection concerns. "External sun protection safeguards health, improves quality of life and simultaneously reduces the energy required for cooling," says Kraler. “What is missing are mandatory standards and widespread subsidies to make effective heat protection accessible to everyone.”

Despite rising temperatures, protection against summer heat is still often treated merely as a comfort feature in new construction and renovation projects. While thermal insulation, heating systems and energy efficiency have long been mandatory elements of building design, comparable standards for protection against overheating in summer are lacking. HELLA therefore calls for heat protection to be consistently integrated into building codes, subsidy programs and renovation strategies. This applies not only to residential buildings but also to office buildings, production facilities, schools, kindergartens, hospitals, long-term care facilities and other public buildings. Interior spaces must remain usable even during heat waves.

Effective heat protection begins at the building envelope. Exterior sun protection - such as roller shutters, external blinds, Venetian blinds, or awnings - blocks solar energy before it reaches the window pane, preventing glass surfaces and interior spaces from heating up. Unlike fans or interior curtains, this solution addresses the root cause and sustainably reduces heat gain. Accounting for an average of just one to three percent of total construction costs, depending on the property, the investment in exterior sun protection is modest compared to the benefits. Additional advantage: Exterior sun protection can be retrofitted in many buildings without extensive renovations. This reduces the need for energy-intensive cooling while simultaneously improving comfort, health and energy efficiency. 

In light of increasing heat waves, external solar shading is becoming a key infrastructure measure for climate-resilient buildings. “From a building physics perspective, exterior solar shading is the most effective measure for heat protection and can be retrofitted within a few weeks,” says Kraler. "The solutions have long been available. What is needed now is technical expertise among decision-makers, clear standards and funding programs that guarantee not only heat supply but also heat protection as a basic service. For better health, a higher quality of life, and greater social justice.”