24/10/2023
Published in
The Conversation
Aurora Monge Barrio
Doctor of Architecture. PCD, University of Navarra
The heat wave that affected the Canary Islands during the first fortnight of October led the agents responsible for schools to order their closure for two days. This fact made the news because of its impact on Canary Island children and because of the unprecedented nature of such an event in the month of October.
As it is foreseeable that these phenomena will be repeated in the future, it seems urgent to develop a protocol for action in these cases (as already exists in Andalusia). But this measure, which also transfers the problem to families, is not enough. It is necessary to adapt buildings to the effects of global warming, specifically to heat waves, and especially in school environments.
Heat waves no longer occur only in summer
Heat waves are one of the main impacts of climate change in Spain. In its annualreport of heat waves since 1975, the Aemet defines a heat wave as "an episode of at least three consecutive days in which at least 10% of the stations considered record maximum temperatures above the 95th percentile of their daily maximum temperature series for the months of July and August of the period 1971-2000".
From agreement with these data, it establishes different thresholds for each locality. Thus, the threshold is 36ºC in Pamplona, 41.2ºC in Seville, 33.2ºC in Santa Cruz de Tenerife and 31ºC in Gran Canaria.
Heat waves no longer occur only in July and August, months when schools are traditionally closed, but also in June, September and even in October, as was the case in the Canary Islands.
Many buildings were conceived only for the school period, so their design is especially oriented to cold winter conditions to reduce heating consumption, but they are not adapted to summer.
Thus, not only are they more likely to overheat in heat waves, but they also make the buildings unusable for summer camps or other activities for children, adults and seniors.
This is why it is necessary and urgent to adapt school spaces to warmer conditions and extreme heat wave events, even in climates with traditionally mild or cool summers.
Insulation, light colors and natural ventilation
In the design of measures, it is advisable to promote those that we call "passive" (because they do not require or require very little energy). When the former are not sufficient to ensure temperatures that affect not only the welfare and academic performance of children, but also their health, it will be accompanied by the installation of the necessary active conditioning systems.
Passive" architectural measures in buildings include insulation in facades and roofs, solar control glazing and shading systems, the use of light colors on the exterior, design with thermal inertia, natural ventilation or the incorporation of nature-based solutions (NBS), such as green roofs or green facades.
Green schoolyards
But it is not only buildings that need to adapt. School playgrounds, often paved as if they were parking lots and not spaces for children to play, also require changes.
The renaturation of schoolyards offers clear benefits when outdoor temperatures are to be reduced. With the added benefit that it will have an impact on reducing indoor overheating of adjacent teaching spaces.
Incorporating nature also offers additional environmental benefits related to improved outdoor and indoor air quality (particulate matter, nitrogen dioxide) and increased biodiversity, as well as benefits related to health and well-being.
Strategies for the renaturation of school spaces are being strongly implemented in different climate change agendas at local, national or European level. It is worthwhile to direct these plans towards a real renaturation, with an appropriate design to the objectives pursued and with adequate tools to test and simulate the efficiency of the solutions.
The approach must necessarily be multidisciplinary, involving architects, landscape architects, biologists, ecologists, engineers and designers. Nature-based solutions need a thorough knowledge of which species are needed in each climate, and which species will be able to adapt to the new climatic conditions or which ones present excessive risk for the climatic zone that discourages it.
There are species particularly suitable for fixing particulate matter or nitrogen oxides, which can be considered in school environments with higher pollution or in environments with heavy traffic.
When choosing species, it is advisable that they are not allergenic species, and that they do not contain fruits that are dangerous for small children. The arrangement of the vegetation can promote provide beneficial ventilation even during the day, and the drainage system also contributes to the reduction of runoff water. Root characteristics will also be another factor to consider in a schoolyard for proper tree growth.
The renaturalization of school buildings and environments is timely and necessary for adaptation to climate change and heat waves. However, its design should be approached by covering a approach multidisciplinary that guarantees adapted, durable and efficient solutions in a medium-term scenario deadline with natural elements that contribute to the play, well-being and health of the little ones.