How to Choose Room Darkening Window Treatments

Types Of Light Blocking Window Treatments

There are numerous options for window treatments when controlling the light in a room or space is desired. From the multiple layer drapes used in hospitality or hotel settings, to curtains lined with a thick polyester fabric layer, none come close to the benefits achieved through interior roller shades.

Many versions of blinds (mini, wood shutters, etc.) are also available to control light entering a space, but rarely will these products have the ability to totally darken a room. In most cases, they must be manually operated.

For a clean, designer look and feel, light filtering roller shades offer the ability to choose a fabric for your desired light control. Total blackout or varied degrees of openness can be specified to achieve beauty and function in both commercial and residential settings.

Light Blocking Window Shade Options

Window shade materials are often described as light filtering, light blocking, room darkening and/or blackout. Here’s how we define different types of shade fabric at Phifer:

What are light filtering shades and can you see through them?

Light filtering window shades are designed to allow natural light into a room or space where total blackout is not desired. The opacity of light filtering shade fabrics determines how much light enters the space. Generally, light filtering fabrics can block 90-98% of natural light.

What’s the difference between room darkening and blackout shades?

Blackout window shades are designed to provide light blockage when complete room darkening is needed.

The primary difference between room darkening and blackout shades is the specified fabric used in them. Room darkening fabrics typically perform similar to a 1-5% openness material, thus blocking 95-99% of light entering the space. Blackout shade fabrics are designed with a solid or laminate on at least one side to allow for nearly 100% blockage of natural light.

Can you see through blackout shades at night?

There is no visibility through blackout shades from the inside or from the outside. An alternative to allow for visibility is a dual shade. Dual shades are engineered with two separate rolls of fabric in a single housing, typically with a standard 1-5% openness fabric facing the room’s interior and a blackout or room darkening fabric facing the back. The shades operate independently to allow for light entry or room darkening, depending upon occupant preference.

Phifer SheerWeave® offers a range of blackout fabrics suitable for use on their own or that can coordinate easily with other SheerWeave fabrics that allow light in during the day when multi-purpose shades are needed.

The difference between solar shades vs. blackout shades

Solar shade fabrics provide solar protection and block sunlight to varying degrees as determined by the fabric’s openness factor. The fabric’s ability to reduce solar heat is measured by the solar heat gain coefficients (SHGC) or shading coefficients, which represent the amount of solar radiation that is transmitted through your window and shading fabric.

Blackout shade materials are engineered to block up to 100% of the UV rays, reduce solar heat gain and maintain optimum temperatures in a residential or commercial environment. Blackout fabrics also have the added benefit of total light blockage and privacy as views through the fabric are eliminated.

Choosing the Right Light Blocking Shades

Consider these benefits when looking for the right material for a window treatment. The top benefits that light blocking shade fabrics can provide include:

Energy Savings

Light blocking fabrics provide excellent reduction in solar heat gain for a more comfortable environment and less work for your air conditioner. By allowing diffused natural light into a room or space, light filtering fabric may also reduce the need for additional interior lighting for added savings.


A growing trend and a popular benefit of light blocking or room darkening shade fabrics is the daytime privacy factor they deliver. Blackout window shades provide the ultimate experience in privacy and can give peace of mind to the occupants in residential or commercial spaces.


With their clean and designer look, light blocking roller shades are a popular and growing trend. With some fabrics being printable, these window treatments can also make a stylish backdrop for signage, graphics and logos.

Flame Resistant

Room darkening fabrics are ideal for commercial applications and are engineered to meet rigorous flame certification standards based on national and local requirements. Check the flame certification standards requirements for your project to verify compliance.

Low VOC Emission

GREENGUARD certification ensures products have met some of the world’s most rigorous and comprehensive standards for low emissions of volatile organic compounds (VOCs) into indoor air.

Glare Reduction

According to OSHA’s workplace guidelines, excess glare in a work space can contribute to eyestrain, tension and lower productivity among the occupants. Shades with light filtering fabrics reduce glare from 70% to 100% depending on color and openness factor.


Light color fabrics provide optimum heat reduction but are more difficult to see through when specified for interior light blocking window shades. Dark colors deliver the best outward visibility and glare reduction but absorb heat and are less energy efficient than lighter colors.


The more open the shading fabric, the more light and heat enters the space and the more outward visibility is maintained. Inversely, more closed fabrics reduce light, heat and visibility but improve glare and UV performance.

The Best Room Darkening & Blackout Shade Fabrics

SheerWeave® blackout fabrics are designed with multiple layers to achieve their room darkening qualities. Most SheerWeave® room darkening shade fabrics are PVC free and made from acrylic-coated polyester to keep light from permeating into interior spaces like bedrooms or nurseries.

All SheerWeave blackout fabrics are designed with energy efficiency in mind and are GREENGUARD® Gold Certified, ensuring products have met some of the world’s most rigorous and comprehensive standards for low emissions of volatile organic compounds (VOCs) into indoor air.  

SheerWeave® blackout fabrics include our: 


Create beautiful roll-up shades that completely block light. With a range of decorator colors that work for commercial or residential spaces, Style 7000 has the look and feel of rich cloth.


This fabric coordinates beautifully with other SheerWeave® fabrics when multi-purpose shades are needed as the face side of Style 7100 is the same as standard SheerWeave® Style 2000. The 7100 face fabric is also infused with Microban® antimicrobial protection to hinder the growth of mold, mildew and bacteria.


Available in a range of versatile colors, the 7200R line is ideal for creating blackout roller shades in residential spaces. It’s also approved by the Melanoma International Foundation and recognized as a fabric for reducing the UV exposure risk of skin and eye cancer.


A picture of refined elegance, Style 7400 layers a subtle textured pattern over a soft luxurious backing for total light blockage.


Offering superior quality at an economical price, Styles 7500 and 7500R fabrics are available in a classic range of neutral colors with a PVC-free composition for use in roller shades and panel track systems.


With a classic linen pattern face and soft PVC-free backing, Style 7600 combines total light blockage with timeless design in a blackout roller shade fabric.


Featuring a soft, textured pattern evoking the look of grasscloth, Style 7700R offers a PVC-free option for total light blockage in residential applications.


Emulating the timeless look of linen, Style 7800 blackout fabric achieves total light blockage with an acrylic foamed backing and decorative polyester face.

Get in Touch with a Representative to Learn More

SheerWeave® light blocking shade fabrics can be fabricated into a variety of custom window treatments that not only eliminate glare and block harmful UV rays, but also reduce energy costs and offer unparalleled privacy in residential or commercial settings.

Phifer representatives are available to chat with you online or on the phone to help answer questions or provide more information. Reach out to our award-winning customer service team any time to let us help you find the right SheerWeave fabric for your light control needs.