You can block heat with aluminum foil by using its reflective properties to redirect sunlight away from a surface.
Aluminum foil is highly reflective, meaning it bounces back light and radiant heat rather than absorbing it. This makes it a simple, low-cost tool for heat blocking in specific situations.
Practical Application: Blocking Heat Through Windows
One common method leveraging this property is spreading tin foil on any windows that receive direct sunlight. As highlighted by the reference, this technique can effectively redirect the sun's rays and accompanying heat away from entering your home.
How it Works
- Reflection: The shiny surface of the aluminum foil acts like a mirror for sunlight.
- Redirection: Instead of passing through the glass and warming the interior, the solar radiation hits the foil and is bounced back outwards.
- Reduced Heat Gain: This significantly reduces the amount of heat entering the room through the window.
Benefits and Considerations
Using aluminum foil for heat blocking, particularly on windows, comes with specific advantages and drawbacks:
- Benefit: It is a very cheap and temporary fix for problems of extreme heat. You likely already have foil available, and it can be applied or removed easily.
- Consideration: The reference notes that applying foil to windows can introduce a "somewhat space-age aesthetic" to your household, which may not be desirable for everyone. It also significantly reduces natural light entering the room.
In summary, the primary way to block heat with aluminum foil is by using its reflective surface to bounce radiant heat and sunlight away from an area, such as applying it to sun-exposed windows.
