Everything You Were Embarrassed To Ask About Aluminum Foil On Windows

aluminum foil on windows

Have you ever walked past a house and seen windows covered with aluminum foil? Yes, many people cover their windows with tin foil for all the right reasons.

If you’re wondering why they do that and should you do it too, you’ve come to the right place. This article has all the answers you would like to know.

Let’s dive in.

Why Do People Put Aluminum Foil on Their Windows?

Aluminum foil is not just useful for baking. It’s a great material with so many uses, one of which is covering windows.

Prevent Heat

People mainly use tin foil to prevent heat that’s coming through the windows. Aluminum is resistant to heat, so it stops heat from the sun.

People usually cover the inside of the window with foil using tapes. Since there’s no direct sunlight coming in, the temperature inside the house stays lower than outside.

Stop Glares

Depending on the position of the windows in your house, direct sunlight may result in glares. It can get difficult to use the mirror or watch something on the TV with the glare directly falling on these objects. The aluminum foil covering on windows reflects sunlight and prevents glares.


It also reduces the amount of light in the room. This works best for people who like their space dark even during the day. For instance, people who work at night and sleep during the day may need the room completely dark.

Reduce Air Conditioning Costs

Mostly, heat in the summer and cold in the winters comes through windows. For those who have large windows in the house, air conditioning bills can get higher. This is why some people opt for aluminum foil covering for windows to keep heat out.

It can effectively keep the indoors cool and help reduce the energy costs, especially during those hot summer months. Since it’s malleable, you can use it to cover any kind of surface and different shapes of windows.

Read also: How Much Does It Cost to Run a Box Fan and How To Cool A Room With No Windows


Tin foil on windows can also provide privacy. Even with curtains, it can be hard to achieve total privacy. As aluminum sheets are opaque, no one can see through them. It’s perhaps the cheapest kind of curtain.

Is it Safe to Put Aluminum Foil on Windows?

There are concerns regarding the safety and practicality of aluminum foil on windows. However, there are no major health or safety risks associated with aluminum foil. After all, we use it in the kitchen all the time.

Aluminum Foil Doesn’t Melt

People think that prolonged exposure to direct sunlight can melt the tin foil. It’s also a common misconception that it’s a fire hazard, catching fire when heated. That’s far from the truth.

Aluminum foil has an incredibly high resistance to heat. It’s melting point is 1220 °F (660 °C), which is way higher than the average temperatures outside in the dead of summer. You don’t have to worry about foil melting in the sun.

Safe Material

Tin foil is a safe material, free from any toxins. The belief that it can rot or emit toxins due to heat has no scientific proof.

Think about it; we use it in the oven while heating or baking food. That’s only possible because it’s safe to do so. At most, it can increase the amount of aluminum in your diet. Now, it doesn’t make sense to worry about that when using it on windows.

Looks Messy

One drawback of covering windows with foil is that it looks messy, especially if you did it hastily. It’s not the most appealing look both from the inside and the outside of the house. However, it gets the job done for preventing heat and light.

You don’t have to do it on all windows of the house. You can just cover those that see the most sunlight. That way, only a few windows would look messy.

Also, if you take your time and do it carefully, it might not look so bad after all. It’s easy, and you’ll master it in a few tries.

Invites Suspicion

Another problem with aluminum foil covered windows is that it might invite unwarranted suspicion from your neighbors or neighborhood watch. Not everyone can know your motive behind this.

They might think that you’re doing something illegal in the house and don’t want anyone to see. If you can deal with stares and gazes when you get out of the house, you don’t have to think twice about this.

Or better, you can tell them your intention behind covering your windows with aluminum foil.

How to Blackout Windows with Foil Properly?

Putting aluminum foil on windows is pretty straightforward. However, you want to do it with care to ensure it does not look messy and serves the purpose.

Here ‘s how to properly to do it:

  1. Measure the windows to get the total area you need to cover.
  2. Add extra three inches to the total length for adjusting and fitting the aluminum sheet to the frame.
  3. You can use insulation like bubble wrap in between the window and aluminum to create a thicker barrier (optional).
  4. Cut the foil according to the measurements of the windows + three inches.
  5. Carefully place the sheet on the glass, flattening it out as you go.
  6. Use masking tape to secure the edges of the sheet to the edges of the window frame.
  7. Make sure that the aluminum covers the glass portion of the window completely.

If the window is bigger than the tin foil sheet, you can simply use multiple sheets to cover the whole area of the window. Use tape to join two pieces on the window. You can also double the sheets or use kitchen foil as insulation.

Avoid using duct tape or scotch tape as it might damage the paint on the windows or the walls. Masking tape is the best option. You can also simply turn the foil sheet over on the window sill and frame to avoid taping altogether.

The Bottomline

To sum it up, there are a lot of benefits of covering your house window with aluminum foil. Using tin foil is a viable solution for blackout and heat prevention. If you live in a populated area, you can use foil as a cheap alternative to blinds or curtains for more privacy and less exposure to noise.