The trick is to use the right type of window shades to block the heat and to install them as close to the glass as possible to get the maximum benefit. For insulation purposes, cellular or honeycomb shades are the most effective. The honeycomb shape helps to trap air, reducing your solar heat gain.
Use window films to reflect heat.
Laminated plastic film is another option for improving window efficiency. Window films reflect a great deal of the sun's energy out of your house. An added benefit is that they block UV rays that damage and fade furniture, rugs, and artwork.
Using Tin Foil Or Cardboard
Tinfoil, or aluminium foil, is a common and inexpensive way to blackout your window.
Materials with a low thermal conductivity like cardboard are perfect for making insulation. These are used to keep heat from transferring between objects or locations. A good example of this is when faced with a window being broken and left without replacements on hand.
Aerogel is more expensive, but definitely the best type of insulation. Fiberglass is cheap, but requires careful handling. Mineral wool is effective, but not fire resistant. Cellulose is fire resistant, eco-friendly, and effective, but hard to apply.
THE ANSWER. Yes. Emergency management agencies specifically recommend using “aluminum foil-covered cardboard” between windows and drapes to reflect heat back outside.
If you are in a pinch, bubble wrap is an excellent insulator for summer windows. Simply spray a light mist of water on your windows, and lay bubble wrap against them to act as another layer of glass. The bubble wrap will stick as long as you need, and it works to keep the hot out and the cold in.
Block the heat
Shade windows and walls using external coverings, like blinds, awnings or large potted plants. Plant deciduous trees that cast shade over your home in summer, but still let the sun shine through in winter.
Insulation. Simply put, this is the best way to cool down a house with big windows. While insulation may be only one word, it needs to be applied in multiple places (and in multiple ways) in order to really be effective in making a home like Jeff's more comfortable so he can enjoy those gorgeous Folsom views.
Aluminum foil can be an effective insulating material because it doesn't radiate heat out into the environment. That's what makes it effective directly under a roof: although it will warm up through conduction from the shingles, it won't radiate that heat out into the attic space.
People seem to like the medium to large size bubbles, but report of smaller bubbles having the same insulating properties are common. The larger ones appear (from surface temperature measurements) to insulate a little better, and you still get a nice artistic effect looking out of them.
What Makes Styrofoam a Good Insulator? The main reason why is styrofoam a good insulator and has become such a popular material for insulation is because of its ability to resist extremes in temperature.
Why does household aluminium foil have one dull side and one shiny side? SO THAT the shiny side can reflect the heat on to the item to be cooked, using a long-established scientific principle that shiny surfaces reflect heat and light.
The Pros of Aluminum Foil on Windows
If you choose this method, it can be a cheap and effective way to keep your house cool. Foil can block up to 95% of the sun's rays and reduce heat gain inside your home. It can also provide privacy and prevent unwanted light from entering your rooms.
Water is a one-of-a-kind substance for many reasons. An obvious one is its unique ability to absorb heat. Water is able to absorb heat - without increasing much in temperature - better than many substances.
Reflective foil, bubble foil insulations, and radiant barriers are noted for their ability to reflect unwanted solar radiation in hot climates, when applied properly.
Apply Heat Reducing Film
With roughly 30 percent of ambient heat coming into your home through the windows, one quick and easy fix to keep your home cool is to apply a reflective, heat-reducing window film to regulate the temperature.
The shiny side should be facing out. Position the piece so that it overhangs the lip of the window by 1 inch (2.5 cm) on all sides. If the window will take 2 or more pieces to fully cover it, consider that too and leave enough room. It also helps if you flatten the foil slightly with your palm.
Applying plastic insulation film to windows can actually cut the cost of heating bills up to 40%, so says Window Resource. Window insulation film helps homes retain heat more easily, keeping you warmer, longer.
It is generally more expensive due to being a metal-based product. It is also important to note that in order for foil insulation to work correctly, it must be kept free of any dust. This means in some areas, such as roofs, it may require being cleaned of dust from time to time to ensure maximum efficiency.
The kitchen foil on windows trick
If you're desperately attempting to keep cool, then take a roll and spread it on your windows - especially those that get direct sunlight. Windows magnify heat, so by using foil you're reflecting the sun off the window, sending it away from your home.