Climate Talk

What makes a building energy efficient? Notes from a retired architect

I worked 35 years designing apartments and offices in Seoul. Many people ask me about solar panels first. But in my experience the order of importance is different.

1. Airtightness. Leaks around windows, doors and pipes waste more heat than people imagine. A blower door check shows this.
2. Insulation and thermal bridges. Balconies and concrete slabs that go from inside to outside are like heat highways. Korean apartments had this problem for many years.
3. Windows. Triple glazing is good, but orientation and shading matter as much. South window with overhang is free heat in winter and shade in summer.
4. Ventilation with heat recovery. If the building is tight, you need fresh air without throwing heat away.
5. Then heating system and solar.

The Passivhaus standard from Germany combines all of this. It is not magic, just careful details. Ask me questions if you are building or renovating, I have time now ^^