6 Best Mildew Inhibitors For RV Awnings That Nomads Swear By

There’s a moment every RVer dreads: unfurling the awning after a rainy travel day only to be hit with that musty smell and the sight of black, speckled stains. This isn’t just an ugly inconvenience; it’s the start of a battle against mildew, a persistent foe in the world of mobile living. The right preventative strategy is your best defense, turning a potential headache into a simple maintenance task.

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Why Awning Mildew Prevention Is Non-Negotiable

Let’s be clear: mildew on your awning is more than just an eyesore. It’s a destructive force that eats away at the fabric’s integrity, whether you have vinyl or acrylic. Those little black spots are living organisms feeding on the material, weakening fibers and coatings until you get pinhole leaks, or worse, a major tear.

Ignoring it is a costly mistake. A new awning can run from several hundred to a few thousand dollars—money nobody wants to spend on a preventable problem. Furthermore, mildew releases spores that can trigger allergies and respiratory issues, compromising the very air in your coveted outdoor living space. Prevention isn’t about keeping things pretty; it’s about protecting your investment and your health.

Think of it like changing the oil in your engine. You don’t wait for it to seize up. You perform regular maintenance to ensure longevity and performance. Treating your awning with a mildew inhibitor is the exact same principle applied to one of your RV’s most-used features.

303 Fabric Guard: Top-Tier UV and Mold Shield

When you ask seasoned nomads what they use, 303 Fabric Guard comes up constantly, and for good reason. It’s not just a waterproofer; it’s a comprehensive protectant. Its primary mission is to restore water and stain repellency to factory levels, which is your first line of defense against the moisture mildew needs to survive.

But its real superpower is its potent UV screening. Sun exposure is what breaks down awning fabrics over time, making them porous and brittle—a perfect home for mold. By blocking harmful UV rays, 303 Fabric Guard keeps the material strong and less susceptible to mildew embedding itself deep within the fibers. It’s a proactive approach, not just a reactive one.

Application is straightforward: spray it evenly on a clean, dry awning until damp and let it cure. It’s especially effective on fabric awnings like those from Sunbrella. The tradeoff is that it’s a protectant, not a cleaner. You absolutely must start with a spotless surface, or you’re just sealing the dirt in.

Star brite Waterproofing for Lasting Protection

If your awning has seen a few years and is starting to "weep" in a steady rain, Star brite Waterproofing is your go-to solution. Born from the demanding marine world where everything is constantly wet, this stuff is formulated for serious moisture protection. It creates a robust barrier that water simply beads up and rolls off of.

Like 303, it also contains UV inhibitors to fight sun degradation. Where it really shines is on older awnings that have lost their original factory coating. A single application can bring a tired, absorbent awning back to life, effectively renewing its primary function and making it a hostile environment for mildew.

One of its best features is that it doesn’t change the color, feel, or breathability of the fabric. It cures without leaving a stiff or sticky residue. Just be sure to apply it thoroughly and allow for proper drying time, ideally on a warm, low-humidity day for the best bond.

Wet & Forget Outdoor: A Low-Effort Solution

For the RVer who prefers a "set it and forget it" approach, Wet & Forget is a game-changer. This product is less of an instant cleaner and more of a long-term preventative treatment. You simply spray it on your awning (a garden sprayer works great) and walk away. No scrubbing, no rinsing.

The formula works with the wind and rain over time to gently clean off stains and inhibit new mildew growth. It’s perfect for treating your awning a few times a year to keep things in check, especially if you live or travel in damp, humid climates. It works slowly but effectively, creating an invisible shield that reactivates with moisture.

The key is managing expectations. This won’t magically remove deep, set-in stains overnight. It’s a maintenance product. For nomads who are constantly on the move, it’s an incredibly simple way to ensure your awning stays clean and protected without dedicating an entire afternoon to scrubbing.

Concrobium Mold Control for Safe Encapsulation

Concrobium works differently from almost everything else on the market. It doesn’t use bleach, ammonia, or harsh chemicals. Instead, as the solution dries, it forms a polymer film that crushes the existing mold spores at their roots and remains on the surface as an invisible antimicrobial barrier.

This makes it an excellent choice for spot-treating problem areas or for nomads who are sensitive to chemicals. If you see a small patch of mildew starting, a quick spray of Concrobium will kill it and prevent it from spreading. It’s colorless, odorless, and won’t damage the fabric.

Because it’s not a waterproofer or a UV blocker, it serves a different purpose. Think of it as your targeted mildew assassin. You’d use this to kill active growth before cleaning and then applying a full protectant like 303 or Star brite for long-term weather resistance.

Mold Armor E-Z House Wash: Powerful Blocker

Sometimes you need the big guns. If you’ve acquired a used RV with a badly neglected awning, or you’ve let things go too far, Mold Armor E-Z House Wash can be your reset button. This is a powerful cleaner that contains a mildewcide to not only blast away existing stains but also block their immediate return.

This product requires care. It’s strong, and you must protect your RV’s siding, decals, and any sensitive materials from overspray. Rinsing thoroughly is non-negotiable. But when used correctly, it can restore an awning that you might have thought was a lost cause.

It’s not a gentle maintenance product; it’s a powerful deep cleaner and inhibitor for tough jobs. Use it once to get the surface pristine, then follow up with a dedicated UV and water-repellent protectant for lasting defense.

Camco Awning Cleaner: The Pre-Treatment Step

It’s tempting to just spray an inhibitor on a mostly-clean awning, but that’s a critical mistake. Mildew feeds on organic material—dirt, tree sap, bird droppings, and general grime. A dedicated cleaner like Camco’s Pro-Strength Awning Cleaner is the essential first step to any successful prevention strategy.

These formulas are designed to break down the specific types of grime that accumulate on an RV awning without using harsh chemicals that could damage the fabric or vinyl. Using a proper cleaner ensures that your inhibitor can bond directly to the awning material itself, not to a layer of dirt.

Think of it this way: you wouldn’t wax a dirty truck. Applying a protectant to a dirty awning is just as pointless. Cleaning is not optional; it is the foundation of mildew prevention. A good cleaning with a purpose-built product makes every other inhibitor on this list work ten times better.

Choosing Your Ideal RV Awning Mildew Inhibitor

There is no single "best" product, only the best product for your specific situation. Your choice depends on your awning’s material, its current condition, and your maintenance style. Let’s break it down.

Start by assessing your needs. Is your primary goal all-in-one protection, or are you fighting an existing mildew problem?

• For comprehensive, proactive protection on a clean awning: 303 Fabric Guard (especially for fabric) or Star brite Waterproofing (great for older, less-repellent awnings) are your top choices. They block UV rays and repel water, stopping mildew before it starts.
• For easy, ongoing maintenance: Wet & Forget is perfect. Spray it on every few months as a low-effort way to keep mildew at bay, especially in humid regions.
• For targeted, non-toxic treatment: If you have active mildew spots or are sensitive to chemicals, Concrobium Mold Control is the safe and effective way to kill spores and prevent regrowth in specific areas.
• For a heavy-duty deep clean and reset: When faced with a severely stained awning, Mold Armor E-Z House Wash will do the job, but use it with caution.

The ultimate strategy often involves a two-step process. First, deep clean the surface with a product like Camco Awning Cleaner to remove all the grime mildew loves to eat. Once it’s completely dry, apply your chosen protectant like 303 or Star brite.

Remember, the number one rule is to never, ever roll up a wet awning. If you have to pack up in the rain, be sure to unroll it and let it dry completely at your very next stop. A little bit of air circulation is the cheapest and most effective mildew inhibitor there is.

Ultimately, protecting your RV awning is about building a simple habit. Pick the right products for your needs, clean before you protect, and always let it dry. A few minutes of prevention each season saves you hours of scrubbing and hundreds of dollars in repairs down the road.