As a brand deeply rooted in the curtain industry for 25 years,

Foulola not only understands your concerns when choosing blackout curtains but also incorporates the stringent standards honed over years of serving top five-star hotels worldwide into the design and craftsmanship of every product.

Today, we break down the essentials of "blackout" by addressing several key questions.

Core Function: How Effective Is the Light Blocking?

What is the actual light blockage level?

We clearly label the light blockage percentage for each blackout curtain, typically ranging from 85% to 100%.

These numbers mean:

1)85%-95%: The room becomes significantly darker, suitable for those less sensitive to light.

2)98%-100%: Achieves near or complete "pitch-black" darkness, ideal for those with high sleep-quality requirements or who need a dark room environment during the day.

Illustration: A comparative diagram showing light blockage levels (gradient from bright to complete darkness with corresponding percentages).

https://www.foulola.com

Will light leak from the edges, top, or center seam after hanging?

This is crucial for real-world performance. Drawing on extensive experience, Foulola offers the following solutions:

1)Ensure Adequate Side Coverage
We recommend the rail/track be 30-60cm wider than the window to ensure the curtains fully cover both sides.

2)Top Light-Leak Prevention
The curtain should extend above the window's top edge. For floor-to-ceiling windows or windows very close to the ceiling, we add an extra 5cm hem at the top edge of the header tape to fill the gap.

3) Center Seam Light-Leak Prevention
Light can seep through the gap between two curtain panels. Three solutions exist:

1.Rail Cutting + Overlap Track: Cut the rail in two and install an overlap track (cross-over connector) in the middle, allowing the panels to meet seamlessly.

https://www.foulola.com/foulola-news-curtain-small-accessories-curtain-rail-crosser

2.Non-Cut Rail + Overlap Track: Install an overlap track directly onto the existing rail to achieve closure.

3.Magnetic or Hook-and-Loop Seals: Use magnetic strips or hook-and-loop tape on the panel edges to force a tight seal.

https://www.foulola.com/foulola-newscurtain-small-accessories-curtain-magnetic-fastenin

Illustration: Diagrams showing the three anti-light-leak solutions for the center seam.

The Principle: Physical vs. Chemical Blackout, Which one is better ?

Common fabrics for blackout curtains include polyester, velvet, linen, and chenille. They generally fall into two categories based on construction:

Physical Blackout (Woven)

Light blocking is achieved through the fabric's inherent density and thickness, typically using a "sandwich" triple-weave technique with a black yarn layer in the middle to block light.

 This is the premium blackout solution we often select for five-star hotel guest rooms.

1)Advantages: Soft hand feel, excellent drape, washable, long lifespan. The dense structure also provides comprehensive benefits like thermal insulation, noise reduction, UV protection, and enhanced privacy.

2)Disadvantage: The light blockage rate generally reaches a maximum of 95%-99%. Darker colors perform better, and achieving a full 100% blackout is difficult.

https://www.foulola.com/foulola-news28/32m-blackout-chenille-jacquard-curtain--fabric----jx/hx/sm

Chemical Blackout (Can achieve 100%)

Most products marketed as 100% blackout use this method, divided into coated blackout and laminated blackout.

Coated Blackout

The back of the fabric is coated 2-4 times with chemical compounds like polypropylene. 

https://www.foulola.com/foulola-news28-34m-666-series-100-blackout-curtain746646

Another layer of fabric can be bonded onto the back for a "double-faced" look, hiding the coating.

https://www.foulola.com/foulola-news666a-super-soft-paint-coating-artwork-100-blackout-curtain

Laminated Blackout

A pre-made industrial blackout film is directly laminated to the fabric back. Similarly, a second fabric layer can be added for a double-faced finish, concealing the film.

https://www.foulola.com/foulola-news-jyn9546-series-100-blackout-light-weight-ready-made-curtain

Comparison of the Two Chemical Blackout Methods:

Feature	Coated Blackout	Laminated Blackout
Light Blockage Stability	A minute chance of pinholes with 2 coats; avoided with extra coats.	Generally no pinholes.
Hand Feel & Drape	Better than laminated, but less than woven physical blackout.	Relatively stiffer, cost-effective.
Thickness & Added Features	If weight reaches 350gsm or above, it can offer thermal insulation and noise reduction.	Usually thinner.
Care Instructions	Dry cleaning recommended; machine washing may affect coating longevity.	Dry cleaning also recommended.

 Can It Have NFPA701 Fire Retardant Functionality?

Yes, but feasibility and cost vary by process. We have extensive experience meeting the FR standards required for hotel and commercial projects.

1.Physical Blackout Fabric: FR treatment can be applied during finishing. No minimum order quantity (MOQ) required. Lower cost.

2.Coated Blackout Fabric: FR components can be added during the coating process. MOQ is around 4000 meters. Higher cost.

3.Laminated Blackout Fabric: Currently difficult to achieve NFPA701 compliance with this process.

A Final Word from Foulola

Blackout is more than just "a layer of fabric"; it's a system combining materials, craftsmanship, and design.

 Our commitment over 25 years has been to translate the expertise and rigor from serving global five-star hotels into every inch of comfort and tranquility for your home. 

As a factory with rich production and project experience, we believe in transparent communication about product features and are ready to recommend the most suitable blackout solution for your specific needs.

If you have questions about specific styles, measurements, or customization, please feel free to contact us — Foulola, dedicated to perfectly managing every ray of light for you.