As the automotive customisation scene hurtles into 2024, side skirts have moved far beyond simple bolt-on trim pieces. These days, they are integral to both a car's visual identity and its aerodynamic performance. Whether you're building a track-focused monster, a weekend showpiece, or a daily driver with attitude, the right side skirts can transform the entire silhouette of your vehicle. For enthusiasts, staying ahead of the curve means knowing which materials, shapes, and technologies are defining the market. Below, we break down the most significant trends in side skirt design for 2024, from aggressive new styling cues to advanced lightweight composites and integrated aero features.

Why Side Skirts Matter More Than Ever in 2024

Side skirts are often overlooked when planning a build, but they serve a dual purpose that few other body panels can match. First, they visually lower the car, creating a seamless line between the front bumper and rear diffuser. Second, they manage airflow along the vehicle's flanks, reducing turbulence and helping to channel air into brake cooling ducts or rear diffusers. In 2024, manufacturers and aftermarket specialists are leaning heavily into this functionality, producing skirts that are as effective at speed as they are parked on the show floor.

Modern side skirts also respond to the growing trend of wider stance builds. As wheel offsets become more aggressive, skirts need to bridge the gap between the bodywork and the tyre face. This has driven the popularity of extended and stepped designs that wrap around the wheel arches. Enthusiasts in the know are pairing these skirts with professional fitment guidance to ensure proper clearance and airflow management.

1. Aggressive Angular Shapes and Multi-Layered Profiles

Gone are the days of simple flat rectangles bolted to the rocker panel. The dominant look for 2024 is sharp, angular, and layered. Designers are incorporating multiple planes, deep recesses, and sharp creases that catch light and create visual depth. These aggressive shapes serve a practical purpose too: the angles can act as air dams, forcing air away from the undercarriage and reducing lift. Many aftermarket kits now feature stepped profiles that drop lower than the main body line, giving the car a planted, race-bred appearance.

Popular examples include the use of integrated strakes or vertical fins along the trailing edge, which mimic the look of GT race cars. These elements are often CNC-machined from billet aluminium or molded directly into the composite material. For those who want to push the envelope, custom carbon fibre skirts with exposed weave and hand-laid layers are becoming more accessible thanks to innovations in composite manufacturing.

2. Lightweight Materials: Carbon Fibre, ABS, and Hybrid Composites

Weight reduction remains a top priority, and side skirts are no exception. Carbon fibre is the gold standard for weight-conscious builds, offering a strength-to-weight ratio that steel or fibreglass cannot match. However, the high cost has led to a surge in high-quality ABS plastic skirts that mimic the look of carbon at a fraction of the price. Many 2024 offerings use a hybrid approach: a carbon fibre outer layer for stiffness and a foam or ABS inner core for impact resistance.

Another material gaining traction is thermoplastic polyurethane (TPU), which is flexible enough to withstand minor scrapes without cracking. This is particularly appealing for lowered cars that frequently contend with driveway aprons and speed bumps. Enthusiasts looking for the best performance-to-cost ratio often turn to comparison reviews on dedicated build platforms to decide between pre-preg carbon, dry carbon, and vacuum-bagged options.

Lightweight materials also affect handling. Reducing unsprung and body weight improves acceleration, braking, and cornering response. Even a few kilograms saved on each side of the car can be felt in hard transitions. In 2024, expect to see more skirts using multi-axial carbon fibre weaves that orient the fibres for maximum impact resistance where the skirt meets the road.

3. Integrated Aerodynamic Features: Diffusers, Splitters, and Ducts

Perhaps the biggest shift in side skirt design is the integration of active and passive aero elements. Many 2024 models feature built-in diffusers at the rear of the skirt that help accelerate air exiting the underbody, reducing lift at high speeds. Some aftermarket designs include small splitters or lips along the lower edge that extend outward to create a ground-effect seal. These are especially effective when paired with a flat underbody panel.

Brake cooling ducts are another common addition. These are moulded into the front section of the skirt, directing air from the front bumper or side intake toward the rotors. This is a race-proven feature that is now trickling down to street builds. Enthusiasts who track their cars benefit from lower brake temperatures, reduced fade, and longer pad life. Ventilated skirts also add an aggressive mechanical look that appeals to the DIY crowd willing to cut and route ductwork.

Some high-end custom shops are even experimenting with active side skirts that deploy at speed, similar to the systems found on hypercars. While still niche, these use electronic actuators and speed sensors to lower the skirt edge when the car exceeds 60 mph, then retract for parking. Expect this technology to become more attainable as production scales up.

Beyond the raw trends, enthusiasts are mixing and matching design cues to create unique looks. Here are the most popular styling directions for side skirts this year:

  • Lowered and Stretched Skirts: These sit extremely close to the ground, giving the car a slammed appearance. They often require modified suspension or air ride to be practical. The visual pay-off is a smooth, uninterrupted line from front to rear.
  • Extended Side Skirts: Wider than factory, these push outward to meet the outer edge of the wheel arch. They are ideal for cars with aftermarket wide-body kits or aggressive offsets. The extended shape also helps smooth airflow past the rear wheels.
  • Color-Matched Accents and Graphics: Instead of a single solid colour, many builds now feature contrasting stripes, pinstripes, or patterned vinyl sections. Some skirts come with a two-tone finish where the lower lip is painted a different shade from the main body.
  • Custom Venting and Light Integration: Functional vents that reduce air pressure inside the wheel well are popular. Some builders integrate LED side markers or sequential turn signals into the skirt for a futuristic look.
  • Removable Sections for Track Use: A practical trend is modular skirts that allow the lower lip to be unbolted for track days, reducing the risk of damage during hard cornering or when mounting curbs.

Material Deep Dive: Which Side Skirt Material Is Right for Your Build?

Choosing the right material affects cost, appearance, durability, and weight. Here is a breakdown of what is trending for 2024:

Carbon Fibre

Best for show cars and lightweight builds. Pre-preg carbon with a 2x2 twill weave is the standard, but 2024 sees a rise in forged carbon fibre, which has a marbled appearance. Dry carbon (without excess resin) is lighter but more brittle. Expect to pay a premium for quality UV-resistant coatings that prevent yellowing.

ABS Plastic

An excellent all-rounder. High-impact ABS is flexible, paintable, and affordable. Many mass-produced skirts use injection-moulded ABS with a textured or smooth finish. It is heavier than carbon but far more forgiving on a daily driver.

Fibreglass

A budget option that is still common. It is heavier than ABS and prone to cracking under stress, but it can be repaired easily with resin and mat. Fibreglass skirts are best for fixed-show builds that rarely see harsh road conditions.

Thermoplastic Polyurethane (TPU)

The newcomer to the mainstream. TPU is rubber-like and virtually indestructible under normal driving. It can bend without cracking and return to shape. Ideal for slammed cars that drag over bumps. The downside is that it is harder to paint and cannot hold sharp creases like carbon or ABS.

Some manufacturers are blending materials, such as using a carbon fibre outer skin with a TPU inner skeleton. This combines stiffness with flexibility, offering the best of both worlds.

Installation Considerations and Fitment Tips

Even the best side skirts will look off if not installed correctly. In 2024, the trend is toward concealed mounting systems that eliminate visible screws or rivets. Many high-end skirts use factory mounting points with custom brackets, while others rely on 3M automotive tape combined with a few hidden fasteners.

Before installing, ensure the rocker panel area is clean and free of rust. Applying a layer of paint protection film (PPF) under the skirt can prevent stone chips and corrosion. For track cars, consider using rivnuts and quick-release fasteners for easy removal. Lowered cars may need to trim the skirt edge to avoid scraping on driveways—many skirts now come with a sacrificial lower splitter that can be replaced.

Alignment is critical: use a laser level or string to make sure both skirts sit at the same height and angle. A misaligned skirt will ruin the car's stance and can create unwanted aerodynamic turbulence.

Performance Impact: How Side Skirts Affect Handling and Efficiency

Side skirts work in concert with the front splitter and rear diffuser to manage airflow. When properly designed, they reduce the amount of high-pressure air that flows underneath the car, decreasing lift. This improves tyre contact patch and stability at highway speeds. On a front-wheel-drive car, a well-designed skirt can reduce rear-end lift, leading to more predictable cornering exit.

Fuel efficiency can also see a small improvement. By smoothing the air along the sides, side skirts reduce drag coefficient, which is especially noticeable on longer drives. However, adding aggressive aero elements like large diffusers can increase drag at low speeds, so there is a trade-off for daily drivers. Enthusiasts who track their cars typically prioritise high-speed stability over marginal efficiency gains.

For those interested in the science, the SAE International publishes research on bodywork aerodynamics, and several aftermarket shops now use computational fluid dynamics (CFD) to validate their designs before production.

Customisation Ideas for a Unique Look

One of the joys of side skirts is how much they can change a car's personality. Here are some ideas that go beyond simple paint:

  • Exposed Carbon with Coloured Threads: Some weaves now incorporate coloured fibres (red, blue, gold) that add a subtle accent.
  • Underglow Integration: LED strips mounted inside the skirt create a glow effect on the ground. This is a retro trend that has been revived with modern RGB controllers.
  • Wrapped Patterns: Use vinyl wrap to create camouflage, racing stripes, or geometric patterns that extend from the skirt onto the body.
  • Hardware Highlighting: Use titanium or anodised bolts as visible fasteners for a motorsport vibe.
  • 3D-Printed Inserts: Custom-designed vent inserts or logo badges can be 3D-printed and glued into recesses.

The key is to complement the rest of the bodywork. A wild side skirt will look out of place on a car with a stock front bumper. Many builders order full aero kits from a single manufacturer to ensure visual cohesion.

Looking Ahead: What to Expect Beyond 2024

The side skirt market is moving toward full integration with vehicle telemetry. Future designs may incorporate sensors that monitor air pressure and adjust active elements in real time. We are also seeing a rise in sustainable materials: manufacturers are experimenting with flax fibre composites and recycled carbon fibre. These materials reduce environmental impact without sacrificing performance.

For now, however, the trends of aggressive angular shapes, lightweight composites, and integrated aero features will dominate 2024. Whether you choose a subtle OEM-plus style or a full race-ready kit, the right side skirts can elevate your build to a new level of style and performance. Stay informed, choose quality materials, and always measure twice before drilling.

For additional reading on aero design principles, the Racecar Engineering website offers technical articles that break down the physics behind bodywork. And for community-tested product reviews, forums like Bimmerpost or Audizine are invaluable resources for real-world fitment and durability feedback.