Millions of people are already exposed to heat waves in Asia and the Pacific, including in the Philippines. Heat waves are periods of abnormally hot weather that are now becoming more common, with a substantial number of people experiencing sub-lethal impacts on their health and productivity.
Deadly episodes of heat waves with air temperatures of 45°C–50°C have been recorded in India and Pakistan in 1998 and 2015.
Our country usually experiences heat waves during the dry season from March to May, posing significant heat-related health risks and other complications. The Philippine Atmospheric, Geophysical and Astronomical Services Administration (PAGASA) has issued warnings about dangerous heat index levels, with some areas experiencing heat indices as high as 50°C.
Today, excessive heat pushes for the adoption of heat-responsive building designs, alongside strict monitoring and enforcement, at the city, municipal, and barangay levels. This will also reduce the exposure of the urban poor to extreme heat.
Also known as climate-responsive architecture, these designs focus on energy-efficient buildings that are well-suited to our climate. These prioritize passive heating, cooling, and ventilation strategies to reduce reliance on artificial energy while reducing energy consumption. Key elements of this design include proper building orientation to sunlight, maximizing natural ventilation, and using energy-efficient windows.
On the other hand, natural ventilation is designed for natural airflow to promote cooling and reduce reliance on air conditioning. These are evident in some centuries-old houses constructed during the Spanish period, since they have large windows. These houses also have ventanillas, or small shuttered windows, enabling good ventilation and natural light, thus helping to lower the hot and humid climate in our country.
Traditional Filipino practices utilized techniques that allow natural air flow in their houses from south to north, aligning with wind patterns during the dry season. Houses, especially those made of indigenous materials such as bamboo, nipa, or cogon, are also elevated to create airflow underneath.
Sun shading is also important; external shading significantly reduces solar heat and improves indoor comfort. Houses use arc-like designs to act as shades on their main doors and windows, insulating the indoor from the heat of the sun.
The Philippine government already has several policies and guidelines on heat-responsive building designs. The Presidential Decree No. 1096, also known as the Philippine Green Building Code, and the Department of Energy (DOE) Guidelines on Energy Conserving Design of Buildings are among the policies that emphasize improving building efficiency and minimizing the negative impact of buildings on human health and the environment.
Aside from national laws and policies, some Local Government Units (LGUs) have their respective ordinances aimed at protecting human health from extreme heat.
The majority of Filipinos are not aware of heat-responsive building design, and an intensive information education campaign is key to raising awareness about it. This will protect vulnerable individuals and families, especially those who suffer the most from extreme heat.
