Yes, aluminum foil can be used over windows to help keep homes cool. Emergency management agencies specifically recommend using aluminum foil-covered cardboard that goes between windows and drapes.
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.
By spreading some foil on your windows which receive direct sunlight, you can redirect the sun and heat away from the house. Other hacks include keeping our window open but curtains drawn and blocking direct sunlight.
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.
Aluminum foil has unique properties due to the fact that it is extremely thin and very shiny. It does not effectively conduct heat nor does it absorb heat, instead bouncing heat waves back outward. This is the reason that even when aluminum foil has been in the oven, it cools almost immediately after being taken out.
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.
The reflective surface will reflect heat and the matte side will reflect less heat . If you're baking or defrosting, the matte side will absorb more radiant heat and reflect less infrared heat while the shiny side will reflect more of both, so it makes more sense to bake and defrost with the matte side facing up.
Keep the Doors and Windows Open
One of the inexpensive ways to cool down your home is to open windows on opposite ends of your house in the evening to let the cool breeze in. Creating a cross breeze will improve home ventilation and help you beat the heat without air conditioning.
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 on windows is most effective at keeping out heat and light when you place it shiny side out and cover its backside with a layer of something else, like insulation or cardboard.
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.
About 30% of a home's heating energy is lost through windows. In cooling seasons, about 76% of sunlight that falls on standard double-pane windows enters to become heat. Window coverings can help with this loss of energy by providing comfort, regulating temperatures, and lowering energy bills.
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.
Make your bed a haven of chill with fans, extra airflow, and low light. Stay on lower levels in your home and minimize heat from electronics and ovens. Opt for light clothing, bedding, pillows, and mattress pads to keep things cooler.
First, check for these common problems: Dirty air filter—A dirty filter restricts airflow, not letting your home get enough cool air. Closed vents—Closed vents in rooms can cause them to be hotter than other rooms. Open windows—Your conditioned air can flow out of open windows, leaving uneven temperatures in your home.
Reynold's Kitchen, an aluminium foil manufacturer since 1947, says: "It's perfectly fine to place your food on either side so you can decide if you prefer to have the shiny or dull side facing out." It's simply a result of the manufacturing process. The performance of the foil is the same, whichever side you use.
So, now that you know the reason behind the different appearance of the two sides, you're probably wondering if you should use aluminum foil with the shiny side up or down. Quite simply, it doesn't matter. Since both sides are made of the exact same material, they will perform exactly the same way.
Insufficient Insulation
Sufficient insulation is necessary when it comes to keeping cool air in and warm air out in the summer. If areas of your home are poorly insulated, you'll likely notice that area is warmer in the summer and colder in the winter compared to the rest of your home.
Window film covers are inexpensive, reduce drafts, help the house feel warmer during winter months, and reduce moisture buildup on the window due to condensation.