The first step toward getting a uniform and light leak-free window treatment is taking precise measurements of your windows. If your measurements are off by even a small amount, your blinds and shades may not completely cover your windows, resulting in small light leaks along the edges.

In addition to taking careful measurements, you should also take into account any size deductions that occur during the manufacturing process by consulting our measuring guides. Blinds and shades that are perfect or near-perfect fits for windows are much less likely to allow large amounts of light to leak into homes.

Blinds and shades that are installed haphazardly and incorrectly are often subject to huge light leaks that can defeat the purpose of having them in the first place. In order to get the maximum effectiveness from your window treatments, it’s important to make sure they are installed correctly. Before attempting to install your new blinds and shades, always consult the manufacturer’s installation instructions or the step-by-step installation guides found on our website.

When installing your new window treatments, make sure the headrail is level and flush with the top of your window. Many light leaks occur at the top of windows due to small gaps between the molding and the headrail. In addition, make sure you install the correct window treatments on the windows they were specifically created for, as your windows may vary in size.

Even the most carefully measured blinds and shades can be susceptible to light leaks when they are installed inside window sills. Because window treatments must fit directly inside the window frame, they must be slightly smaller than the casing itself, which can result in small amounts of light entering the room on the edges of the window.

An exterior mount option places window treatments over the entire window, making light leaks much less likely to occur. Before ordering blinds or shades for an exterior mount option, keep in mind that you’ll need to provide measurement specifications that are a few inches beyond the actual size of your window in order to get adequate coverage.

Although blinds are highly effective at blocking out light and insulating your home, they are more susceptible to light leaks than shades due to their slats. Shades are made with a single piece of continuous material that serves to block out light as uniformly as possible. Blinds are made of many individual pieces of wood, faux wood, or aluminum which can allow small amounts of light to enter rooms.

However, if you prefer blinds over shades and still want the benefit of no light leaks, you can’t go wrong with our 2” Deluxe Faux Wood Blinds. These blinds are designed to be operated without the use of traditional route holes, which means they close more tightly without light leaks through the route holes. That means you get increased privacy, glare reduction, and light control in your home.

Blackout liners not only significantly reduce the amount of light that enters your home, they can also help stop light leaks at the sides and bottom of your window treatments as well. The extra layer of blackout fabric creates an additional barrier between the hot sunlight that’s hitting your window and the inside of your home. This is especially true for shades that are installed inside windows and have very small, but noticeable, light leaks due to small differences between the measurements of the shades and the measurement of the window frame.

This last tip may not be the most glamorous, but it’s highly effective in a pinch. Aluminum foil cut to match the outer edges of your window is highly effective at blocking out light and eliminating light leaks, but it can be unsightly and detract from your home’s appearance.

Another option is to purchase thick foam at a hardware store or large strips of fabric and cut it to the exact dimensions of your windows. As with the aluminum foil, you can adhere it to your windows and help reduce or eliminate any light leaks from entering your home.

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