[DIY] How To Block Sun Heat From Windows-Best Options & Solutions

When the sun’s rays fall into your windows, it becomes warm. Is that also warm in your home? Yes, sun heat can warm your room as well as your home, specifically in summer. So, you can feel irritated and uncomfortable in your home because of the heat.

But is the cooling system enough to block sun heat from windows? The answer is no, the cooling system or fans just increase your electric bill. But not enough to block heat completely from your windows. Now you have to know how to block sun heat from windows?

To block sun heat you can use methods including window blinds, covering windows with foil, use shades or panels, bubble wrap, use awning, and others. These all are DIY project window insulation. But if you just want to block heat and let the natural light in from the window, you can use some temporary techniques.

We have researched deeply to provide you with the right information in detail. And in this article, you will get far better possible, cost-effective ways to block sun heat from windows.

how to block sun heat from windows

How do I Block Sunlight Heat From Windows?

Here you have two choices to block sunlight heat from windows. One of the methods is a window covering installation for a permanent fix. The other technique is an easy and quick way for a better temporary solution. 

1. Installing Window Covering

  • Hang Curtains: Choose the right fabric, size and style of the curtains for your windows. Thicker, dark colour or polyester curtains specially blackout panel curtains can block more sun heat. Spread out the curtains that fully cover the windows. But if you want a little bit of light in, slightly gap between the two curtains.
  • Install Blinds: To block sun heat from windows you can install aluminium, vinyl or wood blinds. Closing the blinds can help to prevent excessive heat. You can use cordless fabric or blackout blinds to block the heat completely.
  • Interior or exterior mount shutters: To block sunlight and reduce heat, this way is great. You can choose shutters made with steel, aluminium, wood and vinyl. Measuring the window, install the right shutters.
  • Install exterior window shades with an awning: To reduce sunlight, outside window coating is a wonderful option. PV and acrylic awnings are more helpful to block sunlight heat from windows.

Check out these Best Solar Shades For Blocking Heat

2. Easy And Quick Solutions

  • Bubble Wrap: If you want to block summer heat temporarily, bubble wrap is a cost-effective solution for you. Bubble wrap can help to insulate heat from the window during summer. And this can also prevent cold air during winter. But the bubble wrapping must be sealed tightly around the window glass.
  • Heat Reducing Window Film: If you want to block sunlight along with seeing the out scenery from the window, a tinted insulating window film is the best temporary solution. Attach the film inside the glass securely. But can window film damaged windows? Sometimes it can damage the windows that create fog and damaged seals.

Check Out>>>Does Window Tinting Reduce Heat In House?

  • Spraying Window Glass: If you want a cost-effective, easy way to block a bit of sunlight, frost spray paint over the window glass is the better option. Spray the window glass with a 1 or thin coat of spray to block sun rays partially.
  • Covering Cardboard: Completely to block the sunlight heat temporarily, covering the windows with cardboard is a quick option. Use painter’s tape to fix the cardboard over the window with the window frame or wall.
  • Cover With Aluminium Foil: Cover the windowsusing aluminium foil to block sun heat. Covering aluminium foil over the window glass can reduce cooling and heating costs insulating the window. Seal the aluminium foil with tape securely. But there remains confusion: does aluminium foil insulate heat? Although aluminium foil is a good insulator, it doesn’t emit heat out from the attic room.


How Do You Reflect Heat Away From Windows?

Reflective window coating can reflect unwanted heat from your windows. This coating is applied to the interior surface of the window.

Check Out>>> Best Home Window Film for Heat Rejection

Another affordable way can reflect heat and cool your home. But will aluminum foil reflect heat?  Aluminum foil can reflect light placing it under the room’s plant, on the room’s wall, and the covering over the window glass. Although aluminum can’t reflect a huge amount of light, that amount helps to reflect heat.

Does Tin Foil On Windows Reduce Heat?

Tinfoil can provide safe coverage like air-tight, heat-proof that reduces heat. When you place tin foil on the shiny side, its backside will be covered with cardboard or insulation that keeps out light and heat. Thin foil is often called aluminum foil.

How Cool Should My House Be If It’s 100° Outside?

An air conditioning system can cool your house around 20° from the outer temperature. If the outside temperature reaches triple digits, your room temperature is set to be at about 78°. You can do anything to block high temperatures and keep cool inside your house.

How Do I Cool Down A Room Without Windows?

Many ways are keeping your room cool down without windows:

  • You can use a floor fan with ice to cool your room. That means a bowl with ice will keep forward to the fan. So that the coldness of the ice cools down your room.
  • Ventless Air Conditioner can cool down a room without windows
  • Put in a wall Air Conditioner without windows
  • Use a ductless AC unit to cool down a room
  • Turn off lights and appliances inside the room when don’t need
  • Keep doors of the room closed so that light or heat can’t come into the room from outside


Does Aluminium Foil Keep Heat In?

Aluminum foil may be an excellent conductor. So it can pass heat easily. Besides, it can also heat out for its insulator feature.

Does Window Tint Keep Heat Out?

Aluminum foil may be an excellent conductor. So it can pass heat easily. Besides, it can also heat out for its insulator feature.

Does A False Ceiling Reduce Heat?

Yes, a false ceiling can reduce heat for thermal insulation. Mineral wool, thermocol cooling agents can reduce heat using between the two layers of false ceiling.

What Can I Put On My Windows To Keep The Heat Out?

You can put three essential materials: blackout curtains, blankets, and awnings/shutters on your windows to keep the heat out. These materials are most efficient and eco-friendly to block sun heat from windows.

Do Window Films Really Reduce Heat?

Yes, window films can reduce around 78% sunlight heat. It can also eliminate unwanted heat to keep your home bright, cool, and comfortable.


Now you have many options to block sun heat from windows. Just choose an option considering your decoration, budget, and your need. Some ways may be costly. But some are user-friendly along with economically affordable including interior and exterior shades, blinds, bubble wrap, window film blackout types. Do you want stylish window methods to block heat? Then choose curtains, awnings, drapes method for your window. Hopefully, you have enjoyed our guide well.