Experimenting With Minergie

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Minergie is theoretically a fantastic, environmentally friendly way of making a building more energy-efficient, by reducing the need for air conditioning and heating. For three years now I have been playing with and experimenting with minergie. During the first and second heatwaves, I liked to open windows and get fresh air. I found that Minergie means “poor air circulation”. As soon as you close the windows you feel the heat radiate from the walls as if they were sauna stones.

With a classic old building the walls are thick and heat stays out, so you never think about open or closed shutters and other things. With an old-fashioned apartment, you can open the windows on both sides and bask in the summer heat. Old apartments are great in heatwaves because you keep your windows open all day long.

With Minergie the experience is different. They eventually begin to feel like ovens, during a heatwave. This year I am trying a different tact. Closed windows, doors, and blinds. So far the experiment seems to be working well. My idea is to compartmentalize the heat. Each room heats and cools by itself. The bathroom and the spare window have veluxes, and these act as radiators in summer, from heat, coming in as sunlight, but also from radiant heat, from the hot glass from being in the hot summer sun. By isolating the oven rooms they warm up in isolation.

I find that some rooms feel cooler, as a result of this strategy. This is a partial success.

My Frustration with Minergie is two-fold. My first frustration is that unlike air conditioning in a car you can’t blast cold air and cool the cabin to a comfortable temperature if it gets too hot. You need to adapt your habits before the heatwave has even started. The second frustration is that with Minergie you cannot open windows and get fresh air as you could before. If you do open windows you need to do so before the day heats up. You open the windows in an attempt to cool down the building’s superstructure.

Although Minergie was designed to keep buildings warm in winter it was never designed to keep buildings cool during yearly heatwaves. In summer Minergie buildings become heat accumulators and, as neighbours in other apartments open windows, and heat up the superstructure, so the top floors become saunas if people are not careful. According to data from last year, the apartment starts to heat up in April and stays warm until Octobre.

Minergie should go back to the conceptual phase and re-imagine how to cool buildings passively, during heatwaves.