Micro-Climate and Indoor Temperatures

Most houses in Portugal have no air-conditioning, and my wife's apartment in Porto is no exception. But we don't miss it much. We rarely get a heat-wave that lasts long enough for indoor temperatures to reach uncomfortable levels, and when we do, we deal with it by going late to bed when temperatures finally drop, and going out to a park by the sea during day.

Heat-waves coincide with summer, so there's a certain charm to them. A summer with no heat-wave would feel strange. However, I'm nevertheless seeking ways to keep our apartment from getting too warm. It's a bit of an obsession with me to figure out how to best deal with unpleasant extremes in the weather.

The most common solution to extreme heat in Portugal is to shutter all windows. This prevents radiation heat from entering houses. However, neither I nor my wife like to shut out natural light. Besides, most of our windows are out of direct sun light, even to the south of the building. There are balconies along the living rooms with shade from the upstairs balconies.

Windows shaded by upstairs balcony

Some of our upstairs neighbours have extended their living rooms to include their balconies, which seems like a terrible idea to me. Not only are they loosing a place to grow plants, they get direct sunlight in through their windows during summer. That makes it all the more difficult to keep their apartments cool. The architect knew what he was doing when he provided every apartment with a shady place to grow plants to the south of the house.

Our success with micro-compost has resulted in much added greenery since last summer, including two small trees that provide extra shade. The hope is that this will result in a micro-climate of sorts, corresponding to the eco-system that has developed around the composts. Less radiation heat will come into out apartment due to more shade, but there may also be an added advantage in the fact that leaves pump water into the atmosphere, thereby lowering the air temperature.

Avocado tree surrounded by green plants

We're also lucky with the location of our apartment. It's situated next to an area with trees and greeneries. This lies to the north of our apartment, allowing for relatively cool air to come in through windows to the north, only to ventilate out through windows to the south. This makes for a pleasant air flow through the apartment.

The green area to the north

An important detail in this is that only the top windows out towards the balcony should be opened. The balcony floor can get very hot, and all that hot air will rush into the apartment if doors are opened. However, the temperature right below the upstairs neighbour's balcony is no hotter than the average air temperature in the area.

When temperatures fall during the evening, we let as much air into the apartment as possible. Very rarely does a heat-wave persist through the night, so we take the opportunity to cool down the house and ready it for the next day before going to bed.