By Jason – Owner, ProPainters Inc. | Trusted Exterior Painting Experts in the Twin Cities.
If you’re a homeowner in the Twin Cities Metro Area and you’ve noticed your Hardie siding fading far earlier than expected, you’re not alone. One of the most common calls we receive is about premature fading on factory-painted fiber-cement siding, especially James Hardie’s ColorPlus boards.
While this product comes with a fade warranty and a reputation for durability, real-world conditions in Minnesota often tell a different story. At ProPainters Inc., we’ve been professionally painting homes since 1995, and we’ve developed a proven system for diagnosing and correcting these issues.
This article will walk you through the key causes of fading, what’s happening below the surface, and what steps we take to repaint and protect your home’s exterior properly.
1. UV Exposure and Directional Sunlight
The biggest contributor to siding fade is prolonged exposure to ultraviolet light. South- and west-facing walls receive significantly more sun, and over time, this causes the factory finish to degrade. This is especially true for darker siding colors like charcoal, navy, or deep green, which absorb more heat and UV radiation.
While ColorPlus finishes are designed to resist fading, Minnesota’s seasonal extremes and long daylight hours can overwhelm even the best coatings.
At ProPainters, we see these patterns constantly. Understanding how sun exposure interacts with paint chemistry helps us choose the right products for long-term performance.
2. Alkalinity Within the Siding Material
Fiber cement is made with Portland cement, which is naturally alkaline. If the material isn’t fully cured or sealed correctly at the factory, alkali salts can begin rising through the surface—a process known as alkali burn.
This leads to the deterioration of the paint film from beneath, even when the finish looks fine initially. This is often misunderstood by homeowners (and sometimes even contractors), but it’s a critical reason for premature failure.
When repainting Hardie siding, we always use alkali-resistant primers designed specifically for cement-based materials. This is one of those small but essential steps that make all the difference in longevity.
3. Efflorescence: A Sign of Trapped Moisture
If you notice white, chalky streaks forming on your siding, that’s a phenomenon called efflorescence. It occurs when moisture inside the material brings soluble salts to the surface. It’s both a visual and structural warning sign.
Efflorescence not only affects how the surface looks but also reduces paint adhesion over time. If ignored, it can lead to blistering or peeling in even newer installations.
This is why we include moisture inspection and surface testing in our estimate process. Understanding what’s behind the surface helps us craft a custom prep plan, not just paint over the problem.
4. Moisture Intrusion and Installation Issues
Even perfectly finished boards can fail if moisture is allowed to enter behind the siding. Gaps in flashing, missing caulking, improper overlaps, and damaged vapor barriers all contribute to this problem.
In homes we’ve repainted, we often find signs of poor installation—areas where water has gotten behind the boards, saturating the substrate and creating pressure that eventually forces its way through the coating.
This is why we take a whole-home approach to exterior painting. We don’t just repaint—we assess water management, material condition, and installation integrity to ensure your new finish will last.
5. Lack of Ventilation and Rainscreen Systems
Fiber cement siding needs room to breathe. Without proper rainscreen systems, weep gaps, or venting behind the boards, moisture has nowhere to escape. Over time, this trapped water accelerates the failure of both the coating and the siding itself.
Unfortunately, tight caulking or sandwiching the siding too flat to the sheathing is a common mistake we see. Even well-intentioned builders can cause long-term issues by skipping ventilation best practices.
As exterior coating specialists, we educate homeowners about these factors and offer optional back-venting upgrades that add real value and lifespan to the entire paint system.
6. Touch-Up Paint That Doesn't Match or Last
Not all fading comes from factory defects. Sometimes, on-site touch-up paint used during installation is not color-matched properly or lacks the UV resistance of the factory finish. Over time, these patches fade at different rates and make your home look blotchy or aged.
Our team takes this seriously. Every repaint includes a full color consultation, careful color matching, and the use of high-performance, UV-resistant coatings to ensure an even and long-lasting finish.
What ProPainters Recommends for Repainting Fiber Cement Siding
If your Hardie siding is fading, here’s our approach as one of the leading exterior painting contractors in the Twin Cities:
- Complete power wash and surface prep to remove chalk, mildew, and failed coatings
- Alkali-resistant primer to seal and stabilize the fiber cement substrate
- High-grade 100% acrylic or elastomeric exterior paint for flexibility and durability
- Flashing and caulking inspection to address moisture vulnerabilities
- Ventilation and drainage recommendations, if needed for long-term success
Our exterior painting projects are never “just another paint job.” They’re part of a bigger plan to protect your home and give you a finish that truly lasts.
Why Twin Cities Homeowners Trust ProPainters Inc.
We’ve been in business since 1995, and we’re proud to be a PCA Certified Painting Contractor serving homeowners across the Twin Cities Metro Area. From new construction to repaints on older homes, we’ve seen what works—and what fails.
When you choose ProPainters, you’re not just getting a crew with brushes. You’re getting a partner who understands the materials, the climate, and the science behind a successful paint job.
We don’t just repaint homes. We help you make smarter decisions that protect your biggest investment.
Call us at: (952) 567-1031
Book your free estimate at: https://calendly.com/propaintersinc/progaragefloors-estimate
Trusted. Certified. Voted Minnesota’s Best.
