When you orient yourself to the construction of a green roof, you probably find that any increase in insulation could ensure that the temperature remains more manageable indoors in summer and winter.
In other words, in summer the green roof would keep it better cooled and in winter the cold could be kept out, keeping heating costs lower in winter. But what’s the real deal? In this article we are going to talk about it.
Instead of an insulating effect, we speak of a regulating effect of heat and cold by a green roof.
Regulating the temperature of a roof in summer
When there is regular roofing on the roof there can be considerable temperature fluctuations in the temperature inside.
The color of the roof, which is often gray, causes heat to be absorbed. With a green roof, the sunlight is actually reflected the moment the sun hits the roof. This helps regulate heat in the summer and keeps it cooler inside.
In cold weather, the regulating effect of the green roof is less due to the fact that the green roof retains moisture. Do you choose a green roof with wildflowers, grasses or herbs? Then there is a better thermal resistance, due to the substrate layer being thicker, so as well as in winter the heating does not have to work as hard.
The temperature with a green roof in summer
As you can imagine, a roof gets warmer when it also gets warmer outside. For your imaging, it can get up to 90 degrees Celsius in the summer on a roof with no planting on it.
When a green roof is installed, an extra layer of roofing material is placed on top of the green roof, so to speak, making the roof thicker including the roofing material and therefore less heat permeable.
Is there actually a green roof then? Then the temperature stabilizes at about 37 degrees Celsius, keeping the heat inside. You can imagine that the sedum, which has a considerable thickness and density and when filled with water, blocks a lot of heat.
The temperature with a green roof in winter
In addition, a roof naturally gets colder the moment it gets cold outside in winter as well. With a green roof, just like in summer, the temperature fluctuates less on the roof, making it less cold inside. Depending on the green roof you install, the cold is better regulated so the heating doesn’t have to work as hard.
You would then say that there is less need for heating in the winter when you have a green roof on your roof as additional insulation, making the temperature in the house ”higher” or less likely to cool. This is one of the many advantages of a green roof. It depends on exactly how much is insulated by the green roof, something that is difficult to say exactly. After all, no formal mathematical value in terms of insulation can be assigned to ”soil”.
You can probably imagine that a wet green roof has different insulation values than a completely dry green roof. So it is difficult to give an exact insulation value of a green roof because there are many different variables involved.
PS. Did you know that walking on a frozen green roof is not convenient?
