Data Center Containment Curtains: What They Are and Why They Matter

If you've ever walked into a server room, you've probably noticed it feels like two different climates in one space: freezing near the cold aisle, sweltering near the hot aisle. That temperature clash is exactly what data center containment curtains are built to solve. They're one of the simplest, most cost-effective upgrades a facility can make, and they're having a moment right now as AI workloads push data centers to run hotter and denser than ever.

At Achilles USA, we don't sell the curtains, but we manufacture the custom PVC film used in them. So we get a lot of questions from converters, fabricators, and facility managers about what these products actually are, how they work, and what to look for. Here's the breakdown.

What Are Data Center Containment Curtains?

Data center containment curtains (also called aisle containment curtains, air containment curtains, or server room barriers) are flexible physical barriers, usually made of PVC strip or panel film, that separate hot exhaust air from cold supply air inside a data center. They hang between server racks to create a "hot aisle" and "cold aisle," stopping the two air streams from mixing.

That separation matters more than it sounds. When hot and cold air mix, cooling systems work harder than they need to, and energy costs climb. Curtains solve this without the expense of a full architectural retrofit, which is why they've become one of the most popular containment methods on the market.

Why This Matters More in 2026

Uptime Institute's 2026 Global Data Center Survey (its 16th annual edition) confirms what a lot of facility teams are already feeling on the floor: rack densities are climbing faster than ever, and cooling is under real strain. The modal, or most typical, rack density hit 11 kW in 2026, up from 9 kW just the year before, marking the first time it's crossed that threshold in the survey's history. Excluding outlier facilities built for extreme density, the average still climbed to 7.8 kW, up from 7.5 kW in 2025.

A few other takeaways from the 2026 survey are directly relevant to containment strategy:

• Operators are effectively planning for two markets at once: high-density AI training clusters that can exceed 30 kW per rack, and CPU-based enterprise workloads that still make up most installed capacity. That split means a lot of facilities now need flexible containment that can be reconfigured as some aisles get denser while others stay conventional, exactly the kind of adaptability strip curtains are built for.

• Power Usage Efectiveness gains remain gradual. The 2026 survey found average PUE (power usage effectiveness) continues to improve only slowly, since legacy infrastructure and cooling constraints are holding back progress even as newer facilities push efficiency forward. Containment remains one of the lowest-cost, highest-impact levers available for squeezing more efficiency out of existing infrastructure without a full teardown.

• Sustainability tracking is back on an upward trend. More than half of operators (53%) now track water usage, up from 47% in 2025, and power consumption remains the most commonly tracked metric at 87%. Better airflow containment directly supports both metrics by reducing the cooling load tied to water-based systems and lowering overall power draw.

• Outages tied to cooling and electrical failures persist. Even as the overall outage rate declines, cooling and electrical disturbances remain the most common cause of the severe incidents that still occur. Containment curtains reduce the odds of localized hot spots turning into equipment failures.

• Operators are staging capacity in phases rather than over-building for peak density on day one, adding power and cooling capacity as workload requirements become clearer. Flexible curtain systems fit that phased approach far better than a rigid, fully custom-built enclosure that locks in today's layout.

  
  

If you are specifying or building containment systems in 2026, remember this: density is changing dramatically. Some aisles need a lot of cooling, while others do not. The curtain systems provide flexibility, and the film behind them must adapt to these differences.

How Curtains Improve Airflow Management

The mechanics are straightforward, but the payoff is significant.

• Isolates supply and exhaust air. Curtains stop cold air delivered through perforated floor tiles from mixing with hot exhaust, so cool air reaches the server intakes instead of dispersing into the room.

• Reduces cooling-related energy costs by 10 to 35 percent, according to Energy Star data on hot aisle/cold aisle layouts.

• Allows higher chilled water temperatures and reduced fan speeds on CRAC and CRAH units, since containment reduces the cooling load overall.

• Increases usable capacity. More stable temperatures mean facilities can safely pack in more equipment without overheating racks, which matters even more now that modal rack density has crossed 11 kW.

• Adapts to almost any layout. Strip and panel curtain systems are cut and configured to fit irregular aisle widths, column obstructions, and retrofit conditions that rigid panels can't handle.

  
  

According to a survey conducted by the Uptime Institute in 2025, 80% of data centers have implemented either hot or cold aisle containment. This marks a significant increase from just 30% in 2014, highlighting the considerable amount of unutilized efficiency in the industry at that time. The evidence suggests that flexible containment designs are advantageous in the long run. As capabilities expand, we will require larger data centers along with containment strategies that are not only effective but also adaptable to a growing infrastructure.

Hot Aisle vs. Cold Aisle Containment: Which Wins?

This is one of the most common questions we see, and honestly, the answer is "it depends on your facility." Here's how the two approaches stack up.

Hot aisle containment

Hot aisle containment seals off the aisle where servers exhaust warm air, keeping it away from the rest of the room.

• Efficiency: Generally the more efficient option, sometimes saving up to 40% more energy than cold aisle containment.

• Installation: More complex, often requiring ductwork or drop-ceiling integration to vent the captured heat.

• Cost: Higher upfront investment.

• Fire code: Can often work with standard fire suppression systems already in place.

• Comfort: Keeps the open floor cool, though the sealed aisle itself runs hot.

Cold aisle containment

Cold aisle containment seals off the aisle delivering chilled air, keeping it from escaping before it reaches the racks.

• Efficiency: Solid energy savings, though generally less efficient than hot aisle containment.

• Installation: Simpler, usually just end doors and a roof cap over the aisle.

• Cost: Less expensive and easier to retrofit into existing spaces.

• Fire code: May require its own fire detection zone, since sealing the aisle can create a "separate volume" under NFPA codes.

• Comfort: The open floor outside the aisle tends to run warmer overall.

  
  

Bottom line: if you're retrofitting an older facility, cold aisle containment is usually the path of least resistance. If you're designing new or chasing maximum efficiency, hot aisle containment tends to pay off more in the long run, just budget for the extra ductwork. Given the 2026 survey's finding that operators are increasingly staging builds in phases, a lot of facilities are choosing cold aisle containment first as the lower-friction option, then layering in hot aisle upgrades as density climbs in specific zones.

Fire Retardant Properties: Non-Negotiable

We see a lot of questions regarding fires retardants when we talk about data curtains, this isn't a coincidence, it's a code requirement in most jurisdictions. Curtain film needs to meet recognized flame propagation standards, especially in cold aisle setups where fire codes may treat the contained space as separate volume requiring its own detection or suppression plan. This becomes even more important as densities rise, since higher-density racks generate more heat and carry more electrical load, both of which raise the stakes if a fire event does occur.

The standards that matter most:

• NFPA 701, the standard test for flame propagation of textiles and films, is the industry benchmark for curtains, draperies, and dividers in commercial and public spaces.

• NFPA 75 and 76, which govern fire protection specifically for information technology equipment and telecommunications facilities.

• CSFM Title 19, required for curtains and films installed in California commercial and public facilities.

• ASTM E84, which measures flame spread and smoke development.

  
  

Achilles USA formulates and tests PVC film against all of these, along with CPAI-84 and UL 94 HB, depending on the application and jurisdiction. Fire retardancy isn't an add-on feature when it comes to Data Curtains, it's needs to be baked into the formulation from the start.

Where PVC Film Fits: The Material Behind the Curtain

This is where our expertise comes in. A containment curtain is only as good as the film it's made from, and not all PVC is created equal.

At Achilles USA, we've supplied the domestic industrial market since 1973, and our data center containment films are custom-formulated for the specific demands of server room environments:

• Fire-rated formulations tested to NFPA 701, ASTM E84, and other standards depending on jurisdiction.

• Anti-static properties to protect ESD-sensitive electronics, an important consideration since server rooms are full of exactly the kind of sensitive components that static discharge can damage.

• Thickness range from 5 mil to 120 mil, so converters can dial in the right balance of flexibility and durability for strip curtains versus rigid panel sections.

• Clear, opaque, or tinted options, plus finishes like double polish or matte, depending on visibility and aesthetic needs.

  
  

For projects that also require advanced ESD protection, our imported Seiden series incorporates conductive grid technology. Seiden-F and Seiden Crystal films combine flame resistance with printed conductive grids to achieve surface resistivities as low as 10⁶ Ω, originally engineered for cleanroom and electronics environments but well-suited to data center partition applications where static control is critical. The Seiden series is imported straight from Achilles Corporation and distributed by Achilles USA.

Traditional Barriers vs. Flexible Curtains

If you're weighing curtains against rigid enclosures or Plexiglas panels, here's the short version: curtains win on cost and flexibility, rigid panels win on durability and airtightness.

Flexible PVC curtains are cheaper to install, easier to retrofit into odd-shaped aisles, and simple to modify as rack layouts change. Rigid containment (glass, polycarbonate, metal-framed panels) creates a tighter seal and holds up better to heavy foot traffic, but it costs more and is much harder to reconfigure later. Plenty of facilities use a hybrid approach: rigid end-of-row doors paired with flexible strip curtains along the sides, since it captures the airtightness where it matters most without the full cost of an all-rigid buildout. That flexibility lines up well with the phased build strategy operators reported favoring in the 2026 survey.

Ready to Build Your Containment Solution?

If you're a containment system manufacturer, fabricator, or environmental and spill containment provider looking for the right material to build your next containment solution,  let's talk about what your application needs! Whether that's fire-rated film for cold aisle enclosures, anti-static Seiden film for ESD-sensitive zones, or a custom thickness that balances flexibility with durability.

Achilles USA has been engineering PVC film for industrial applications since 1973, and we'll work with you to get the formulation right the first time. Fill out our contact form , and we'll get back to you to discuss your project.

FAQ: 

What thickness of PVC film is best for containment curtains?

Most data center strip curtains run between 20 and 80 mil (0.020 to 0.080 inches), depending on the application. Thinner gauges (20 to 40 mil) are common for interior strip sections since they stay flexible and easy to overlap, while thicker gauges (60 mil and up) show up in end panels or high-traffic areas where durability matters more than flexibility. As a rule of thumb, 100 gauge equals 1 mil, so a 2,000-gauge vinyl is the same as 20 mil. Achilles USA formulates and laminates film anywhere from 5 mil to 76mil, so the right thickness really depends on whether you're building flexible strips or semi-rigid panel sections.

Why is PVC used more than other plastics for these curtains?

PVC holds its clarity longer, resists yellowing, and can be engineered with a much wider range of thickness, texture, and fire-retardant additives than polyethylene or most other film-forming polymers. Polyethylene is lighter and cheaper, but it degrades faster without added stabilizers and doesn't hold up as well to repeated flexing at the strip overlaps. Polyurethane is a strong alternative if you need extra flexibility retention in cold environments, but it typically costs more and needs UV stabilization just like PVC does.

Does PVC film curtain material degrade over time?

Yes, but the rate depends heavily on the stabilizer package and UV exposure. Untreated PVC can yellow and become brittle under prolonged UV exposure, while properly stabilized, industrial-grade PVC can last anywhere from 5 to 20 years depending on thickness and environment. That's a big range, and it comes down to formulation. Achilles USA's own research shows that the right combination of film grade, UV stabilizers, and thickness can double or even triple a film's usable lifespan in demanding conditions.

Do data center curtains need to be anti-static?

In most cases, yes. Server rooms are full of ESD-sensitive components, and a static discharge from a curtain brushing against a hand or a cart can cause real damage. Anti-static PVC film is typically formulated with conductive additives or printed conductive grids to bring surface resistivity down into the 10⁶ to 10⁹ Ω range, which is enough to dissipate static safely without creating a shock hazard. If your facility handles high-density racks or frequently swapped hardware, this isn't optional; it's a baseline spec, and it becomes even more important as rack densities climb toward the 11 kW modal figure reported in 2026.

What's the difference between "fire retardant" and "flame resistant" film?

These terms get used interchangeably, but they describe different things. Flame resistant generally means the base polymer itself resists ignition. Fire retardant (or flame retardant) usually refers to a film formulated with additives to slow flame spread and self-extinguish once the ignition source is removed, which is exactly what standards like NFPA 701 test for. When you're sourcing curtain film, always ask for the specific test standard and pass/fail data, not just a general "fire retardant" claim on a spec sheet.

Can PVC curtain film handle humidity and temperature swings in a server room?

Quality industrial PVC film handles the moderate humidity of a typical data center without issue, since server rooms are climate-controlled by design. The bigger risk is moisture combined with poor storage or installation, since excess humidity trapped against film can promote mold or mildew growth on the surface over time. For most indoor containment applications, standard fire-retardant PVC film is well within its comfort zone. If curtains are installed near loading docks or areas with more temperature swing, ask about cold-crack resistance so the film doesn't stiffen or crack in cooler zones.

How do I know if a film supplier can customize thickness, color, and fire rating together?

Ask for a samples, work with the engineers and design teams to reach the work on the right properties for your application. A converter or fabricator worth working with should be able to show you film samples across multiple thicknesses, understand your required fire rating, and in the color or clarity you need, without treating those as three separate product lines. Achilles USA custom-engineers film this way, combining thickness, flexibility, color, and performance additives (fire retardant, UV-stable) into a single formulation built for the specific application rather than a one-size-fits-all roll.