Waterproofing and Sealing: Protecting Corrugated Plants from High-Moisture Environments

Moisture is one of the least discussed and most damaging forces at work inside a corrugated plant. Unlike a broken machine or a failed floor coating - problems that announce themselves clearly - moisture damage is cumulative and often invisible until it has already done significant harm. By the time rust appears on structural steel, water stains show on interior walls, or a roof leak finds its way onto the production floor, the underlying deterioration has usually been underway for months or years.

For corrugated and packaging facilities, this slow, hidden damage has outsized consequences. The manufacturing environment itself generates substantial moisture - from corrugator steam systems and starch application processes to wash-down areas and the ambient humidity drawn into a large, high-bay building during warm-weather months. Add external weather exposure across decades of operation, and many corrugated facilities are dealing with moisture infiltration from both inside and outside simultaneously.

At Kelly Industrial Services, waterproofing and moisture protection are a core part of the comprehensive maintenance programs we build for corrugated and packaging facilities nationwide. Here’s what facility managers need to understand about how moisture damages corrugated plants - and how to address it before it becomes a structural and operational liability.

Where Moisture Comes From in a Corrugated Plant

Understanding moisture management starts with identifying the sources. In most corrugated facilities, there are at least three distinct moisture pathways at work simultaneously:

Process moisture is generated inside the facility by the corrugating process itself. Steam shower rolls heat and condition the fluting medium before it enters the corrugating rolls. Starch is applied at elevated temperatures and begins drying immediately, but the evaporation process releases significant moisture into the surrounding air. These are continuous moisture sources during every production run - and in a facility running multiple shifts, that means continuous moisture generation for 16 to 24 hours a day.

Weather infiltration enters through the building envelope - primarily through aging roof systems with failed seams, caulking, or flashing at penetrations. Even small roof leaks allow water to enter during rain events, saturating roof deck insulation, migrating along structural steel, and eventually finding its way to the production floor or ceiling grid below. What starts as a single point of failure expands laterally over time, as water follows the path of least resistance through degraded materials.

Condensation is a particular challenge in large, high-bay corrugated buildings where warm, humid interior air meets cooler structural surfaces. Steel roof decking, purlins, joists, and wall panels can all serve as condensation surfaces, particularly during seasonal temperature transitions. That condensation doesn’t drain away cleanly - it sits on horizontal structural surfaces, accelerates rust formation, and contributes to coating breakdown.

The Consequences of Unmanaged Moisture

Controlling moisture in corrugating areas is not just a structural concern - it affects nearly every operational system in the facility.

Rust and structural corrosion are the most visible long-term consequence of moisture exposure on steel structures. A corrugated plant’s structural steel - columns, joists, purlins, and roof decking - represents a major capital investment that, once significantly corroded, requires expensive remediation or replacement. Surface rust that can be addressed with wire brushing and a fresh coat of paint is a manageable maintenance task. Corrosion that has penetrated deeply enough to compromise load-bearing cross-sections is an engineering and safety problem. The path between those two conditions is simply time and moisture.

Roof system failure has immediate operational consequences. Water on a corrugated plant production floor is a safety hazard, a product quality risk (wet board and finished goods are a write-off), and a machinery risk - water near electrical systems, corrugators, and control panels creates damage and outage risks that can be catastrophic. A degraded roof system also increases the facility’s energy costs, as failed insulation loses R-value and allows thermal transfer that forces HVAC systems to work harder.

Coating breakdown on walls and structural surfaces creates a cascade of secondary problems. Once moisture penetrates behind a wall coating, the coating begins to delaminate and bubble. Exposed concrete block or steel substrate is then directly exposed to the facility’s process moisture and cleaning chemicals. Starch residue, which is hygroscopic (moisture-attracting), adheres readily to degraded surfaces and accelerates further deterioration. The visual impact on a facility’s appearance also affects employee morale, customer perceptions during facility tours, and audit findings.

Machinery corrosion is a direct consequence of moisture-rich environments. Corrugated plants that don’t actively manage moisture levels experience higher rates of surface rust on machinery frames, roll housings, and structural assemblies - even on equipment that is regularly cleaned. Preventing rust in corrugated plants requires addressing the ambient moisture environment, not just cleaning equipment surfaces.

Roof Coatings: The Most Impactful Single Intervention

For most corrugated facilities dealing with moisture problems, the roof is the highest-leverage intervention. A failed or aging roof system that allows water infiltration is compounding every other moisture management effort inside the building. And unlike a full roof replacement - which is one of the most expensive capital expenditures a facility can face - a fluid-applied industrial roof coating system can seal an existing roof surface, restore waterproofing integrity, and extend the useful life of the roof system by a decade or more at a fraction of replacement cost.

Roof coatings for corrugated plants need to meet specific performance criteria. They need to accommodate the thermal movement of large metal roof panels without cracking or separating at seams. They need to be formulated to handle the UV radiation and temperature extremes that industrial roofing surfaces experience. They need to maintain adhesion over roof penetrations, drains, and equipment curbs - the most common failure points on industrial roofs. And they need to be applied safely and efficiently with minimal disruption to the production environment below.

Our roof coating programs begin with a thorough assessment of the existing roof condition - identifying failed seams, damaged flashing, blocked drains, and surface deterioration - followed by targeted preparation and a staged application process that works around facility operations. The result is a sealed, reflective roof membrane that stops infiltration, reduces cooling loads, and provides documented protection for the building envelope.

Wall Waterproofing and Protective Coatings

Inside the facility, waterproofing corrugated facility walls requires a combination of surface cleaning, surface preparation, and the application of protective coating systems designed for the specific exposure conditions present. Many corrugated plants have interior wall surfaces that have never received anything beyond standard interior latex paint - which is wholly inadequate for an environment with process moisture, chemical exposure, forklift impact, and decades of maintenance history.

The correct approach layers preparation with protection. Our industrial facility painting programs for corrugated facilities start with thorough facility cleaning - removing the accumulated starch, fiber, grease, and contamination that would prevent proper adhesion of new coatings. Surface preparation then addresses any existing coating failures, rust, or substrate damage. Finally, high-performance epoxy or urethane coating systems are applied - selected for moisture resistance, cleanability, and the ability to withstand the mechanical impact inherent in high-traffic corrugated environments.

In areas of particularly high moisture exposure - near corrugators, starch systems, or wash-down zones - we specify coating systems with enhanced moisture vapor transmission resistance and chemical resistance, ensuring the coating system remains intact and protective even under continuous exposure.

Structural Steel: Stopping the Rust Cycle

Preventing rust in corrugated plants requires treating structural steel as a maintenance asset, not a permanent given. The original protective coatings applied to structural steel during building construction were not designed to last indefinitely in a corrugated plant environment, and they don’t. Once those coatings fail, surface rust begins, and without intervention, it progresses.

Our approach to structural steel maintenance in corrugated facilities begins with facility cleaning to remove dust, fiber, and surface contamination from steel members. Where surface rust exists, mechanical preparation - wire brushing, power tool cleaning, or blast cleaning for heavily corroded surfaces - brings the substrate back to a condition that will support proper coating adhesion. We then apply industrial-grade corrosion-inhibiting primer and topcoat systems, using products formulated for the thermal, moisture, and humidity exposure conditions present in corrugated manufacturing environments.

This work is often combined with broader facility painting programs during planned shutdown windows, allowing us to address both structural steel and wall/ceiling surfaces in a single coordinated mobilization.

A Comprehensive Moisture Management Program

The most effective approach to controlling moisture in corrugating areas is not a single service - it’s a coordinated program that addresses all three moisture pathways (process, infiltration, and condensation) with appropriate interventions at each point. A complete program typically includes:

• Industrial roof coatings to seal the building envelope against external water infiltration
• Facility painting with moisture-resistant coatings on walls and structural steel
• Facility cleaning to remove dust and fiber that trap moisture against surfaces
• Machine cleaning and conveyor cleaning to protect equipment from the combined effects of process moisture and contaminant buildup
• Pit cleaning services to remove standing moisture and debris from below-grade areas
• Boiler painting services with heat and moisture-resistant coatings on steam systems and high-temperature surfaces

Because all of these services are delivered by Kelly Industrial’s in-house team - every technician a full-time employee, never a subcontractor - they can be coordinated across a single shutdown window with one point of contact, one safety plan, and one set of documentation. That integrated approach is more efficient than managing multiple specialized contractors separately, and it produces better outcomes because our teams understand how each service area interacts with the others.

Protect Your Corrugated Plant From the Inside Out

If your corrugated facility has signs of moisture damage - visible rust on structural steel, roof leaks, wall coating failures, or equipment corrosion that cleaning alone can’t reverse - the underlying moisture pathways need to be addressed, not just the symptoms. Contact us today to schedule a facility assessment and discuss a moisture management program tailored to your plant’s specific conditions. And visit our resources and blog for more insights on facility maintenance best practices for corrugated and packaging operations.