There is a simple solution to increase solar gain through glazing and improve winter thermal comfort without doing any work.
Just wash your windows!
All you need is a cloth and window cleaner, or just a little water, dishwashing liquid and vinegar, if you want a homemade recipe.
Glazing is characterized by a certain transmission factor, which expresses its capacity to transmit solar radiation inside a room (not to be confused with the solar factor).
It will depend on the number of glazings, the composition of the glass and its surface treatment (indium-tin oxide, silver, etc.).
It varies between 0.90 for single glazing and around 0.60 for triple.
Except that these figures are given for new glazing from the factory.
According to a study published in 2001, dust and dirt on vertical glass causes a decrease of the transmission of solar radiation by approximately 5% compared to clean glazing.
This is particularly the case in urbanized areas due to the action of air pollution.
5% doesn't seem like much, but on the scale of a large surface area of glazing over an entire heating season, it represents a significant difference.
Hence the importance of cleaning your windows regularly.
As for whether this has an impact on your heating bill, the subject remains to be debated!
Regardless of the savings, washing your windows can't hurt.
To our rags!
Sources: A. De Herde, A. Liébard, A. Hegazy.
Image: Unsplash, CDC