Keeping Cool in a Heat Wave

We are currently in a heat wave. During heatwaves my velux heat up in the afternoon sun and radiate heat both into the apartment during the day but also at night after the sun has set. I have found that during a heat waves it is wise to close the blinds and close the windows as soon as it is hotter outside than inside.

When it is hotter outside than inside closing windows keeps the apartment slightly cooler, but not much cooler. As I write this it’s 11am and the bedroom is at 30°c. I had cooled it down to 27°c earlier this morning but as soon as I close the windows the apartment temperature shoots up because the core is hot.

The problem with this building is that it’s designed to be hot in winter which is fantastic. All year round I can be at a tropical 25°c or hotter. The issue is that in summer that ability to trap heat backfires because an apartment goes from being comfortable to being deeply uncomfortable.

Sources of Noise Pollution

The issue isn’t really with the apartment, but with the neighborhood. At least two or three people do metal work in a yard where a farmer likes to park tractors, refill with water and more, and clean other things. This is one source of noise pollution.

The second source of noise pollution is construction. One year it was a roof being redone, another year it was a building being built, and yet again it’s a building being built, after the noise of the destruction.

Add to this people on their balconies talking and smoking all night long, or the pétanque players on Sundays, and the freedom to open windows is gone. In a well designed minergie building cold air would be blown into the building when it’s warm outside. In this building there is no airflow so the air is stagnant, and that is what makes the heat so uncomfortable.

There is also the sound of a quarry nearby, and canons to frighten birds away from birds that add to the noise pollution. All night long you have the noise of the motorway. What we thought was just background noise before the pandemic was highlighted as noise pollution after lockdown ended.

If it wasn’t for noise pollution and smokers I would open the windows in the morning, and close them before sunset. That’s what I have done in offices near Meyrin, at the Palais Wilson, in another village where I lived, and an apartment in Meyrin. It’s only here that I find it very hard to keep windows for any length of time.

Before living in this apartment I didn’t understand why people suffered with the heat, and why people would sit on chairs underneath a tree in the countryside. Now I do. I find that when the apartment turns into a hammam/sauna it’s better to go for a walk, with a hat, and water, in the 37°c heat of the sun, than to sit and stew in the apartment with no air flow.

With better noise pollution regulations, and a ban on smoking during heatwaves I would be comfortable despite the heat wave. I usually love heat.

The Heat Sink Staircase

The key issue with this building is that the apartments are built around the central staircase. When it’s cold outside this is fantastic, because heat rises and warms up the top floors but in summer that staircase becomes a thermal battery that heats up in summer. In summer those in the floors beneath open their windows, which allows heat into the building and that building heats their apartments, but also the cement and other materials. That heat rises and that’s why, even when it’s 15°c outside the building is 27°c indoors as soon as you close windows.

Out of curiousity I have been playing with an Aranet 4 to see whether my feelings are emotional or rational. If I open a window the temperature will drop by three or four degrees within a few minutes. If I close the window then the temperature shoots back up within minutes, especially at the moment.

I also found that having the velux open does cool the room up to a certain point, but once the sun starts heating the building the apartment starts to heat up despite the velux being open.

If the central staircase had a vent then convection currently would naturally pull cool air from the basement to the top floor, cooling the entire building. In this building hot air is trapped, unable to escape. Even in winter I am comfortable in a t-shirt.

The Hottest Working Environment

Although I worked as a luggage handler during a heat wave this was not the hottest environment. The most uncomfortable office environment was in the Palais Wilson on the ground floor. Outside was tarmac and other buildings that would radiate heat. There was no air flow so I could be drenched, from simply sitting down at the desk.

Eventually I found an excellent solution. If I opened the office door just a little, and the window as well, then I got a nice breeze to cool down the office/studio. As soon as I found this solution I was comfortable.

A normal person achieved the same effect, with a fan. I still prefer using natural cooling solutions when I can.

Solutions

The solution to not being able to use a natural breeze to cool down during the day is to buy and use fans. On previous nights I was able to cool my hammam/bedroom to a comfortable 27°c before going to sleep but yesterday it was at 30°c so I used a small USB fan to cool down for the entire night. I have another warehouse fan that I use to blow air up the stairs to the attic, to create air flow, and to vent via two velux.

The other obligation is to keep shutters closed on the sunny side, until the sun vanishes from view. That’s when I can open some shutters and open windows, once the balcony heat trap is diminished.

And Finally

In the grand scheme of things the temperature varies from 23°c in winter to 30°c in summer during heat waves. Normally I would use open windows to get an air flow but because of noise pollution I use fans. I could be absurd and use an air conditioner to cool things down but that goes against my code of ethics, because air conditioners cool on one side, and heat on the other. Fans just blow air from Point A to Point B and our bodies cool themselves thanks to the circulation of air. That’s what has kept me cool through every heat wave I have experienced, until living in this building.

The current heat wave should be over by tomorrow evening but the heat that the building has absorbed will take months to dissipate. Rain is also forecast for this afternoon which should help cool things a little.