## [hero] Product hero

- [hero-tag] Professional cool roof coating for metal roofs
- [hero-product-name] CovaMetal 20
- [hero-tagline] The 3-in-1 cool roof coating for corroded metal roofs.
- [hero-description] Elastomeric resin with anti-UV Top Coat, designed by Covalba, a specialist in reflective cool roof coatings. A single application treats corrosion, restores waterproofing, and delivers up to 10°C cooler indoors, with a 20-year warranty.
- [hero-image-alt] Application of CovaMetal 20, a cool roof coating, on a corroded steel deck roof
- [hero-primary-cta] Request a quote
- [hero-secondary-cta] Download the technical datasheet
- [hero-badge-1] SRI 107
- [hero-badge-2] 20-year warranty
- [hero-badge-3] Anti-corrosion protection + cool roof
- [hero-stat-1-value] 8 to 10°C cooler
- [hero-stat-1-label] Indoor temperature
- [hero-stat-2-value] 20 years
- [hero-stat-2-label] of anti-corrosion + cool roof
- [hero-stat-3-value] 3-in-1
- [hero-stat-3-label] Anti-corrosion, waterproofing, cool roof
- [breadcrumb-home] Home
- [breadcrumb-solutions] Our solutions

## [showcase] Product positioning

- [showcase-eyebrow] Positioning
- [showcase-title-line1] CovaMetal 20, the 3-in-1 cool roof
- [showcase-title-line2] for metal roofs.
- [showcase-card-eyebrow] The 3-in-1 cool roof coating
- [showcase-card-title] CovaMetal 20
- [showcase-card-intro] A single application simultaneously treats the three recurring problems of aging steel deck roofs: corrosion, leaks at sheet overlaps, and summer overheating.
- [showcase-point-1] Anti-corrosion — stops the spread of rust on exposed metal.
- [showcase-point-2] Waterproofing — elastic membrane with 200% elongation at sheet overlaps and fastening points.
- [showcase-point-3] Cool roof — up to 90% of solar radiation reflected, over 20 years.
- [showcase-cta] Request a quote
- [showcase-footer-note] Is your roof a corroded steel deck? Request a quote to assess your project.
- [showcase-footer-link] Request a quote
- [showcase-image-alt] CovaMetal 20 system: Base Coat and Top Coat containers, cool roof coating for steel deck by Covalba

## [compatibility] Compatible substrates

- [compat-eyebrow] Compatibility
- [compat-title-line1] The substrates compatible
- [compat-title-line2] with CovaMetal 20.
- [compat-coverage-note] An anti-corrosion cool roof coating delivers on its promise only if it bonds durably to the metal substrate.
- [compat-1-type] Steel deck
- [compat-1-detail] Galvanized, painted or bare sheets, with or without corrosion. Core target.
- [compat-2-type] Corrugated metal sheeting
- [compat-2-detail] Corrugated or ribbed sheets, with or without surface corrosion.
- [compat-3-type] Zinc
- [compat-3-detail] Aging zinc roofs, adhesion verified by prior testing.
- [compat-4-type] Other metal substrates
- [compat-4-detail] Compatibility validated after an on-site technical assessment.
- [compat-label-compatible] Compatible
- [compat-label-incompatible] Not compatible
- [compat-glass-warning] Do not apply CovaMetal 20 on glazing. On glass, skylights or verandas, an interior-applied solar film delivers a far better appearance and superior durability. For translucent polymers (polycarbonate, polyester), CovaMetal 20 remains the suitable solution.

## [specs] Technical characteristics

- [specs-eyebrow] Technical characteristics
- [specs-title-line1] The characteristics
- [specs-title-line2] of CovaMetal 20.
- [specs-intro] Anti-corrosion, reinforced waterproofing at critical points, cool roof reflectivity over two decades. CovaMetal 20 is designed for industrial and commercial steel deck roofs that owners want to keep rather than fully replace.
- [specs-row-1-label] Technology
- [specs-row-1-value] Elastomeric acrylic resin + anti-UV Top Coat finish
- [specs-row-2-label] Substrates
- [specs-row-2-value] Galvanized, painted or bare steel deck + corrugated sheeting, zinc
- [specs-row-3-label] Reflectivity index — SRI (as new)
- [specs-row-3-value] 107
- [specs-row-4-label] Coating system
- [specs-row-4-value] Base Coat 400 to 800 g/m² + Top Coat finish
- [specs-row-5-label] Maintenance recoat due after
- [specs-row-5-value] 20 years
- [specs-row-6-label] Reinforced protection against soiling
- [specs-row-7-label] Reinforced waterproofing
- [specs-row-8-label] 3-in-1 cool roof effect
- [specs-row-8-value] Included
- [specs-cta] Request a quote
- [specs-badge] 3-in-1
- [specs-footnote] SRI measured per ASTM 1980 standard · 20-year manufacturer warranty · Covalba R&D data

## [certifications] Performance and compliance

- [cert-eyebrow] Performance
- [cert-title-line1] Certified performance and
- [cert-title-line2] characteristics.
- [cert-intro] CovaMetal 20 meets the technical and environmental requirements of industrial buildings: external fire resistance, low-VOC formulation, and durable cool roof reflectivity cover every steel deck renovation project.
- [cert-1-label] Broof(t3)
- [cert-1-desc] External fire resistance classification, the most demanding level for an industrial roof.
- [cert-2-label] Liquid waterproofing membrane
- [cert-2-desc] Continuous elastic film that seals sheet overlaps, fastening points and details across the entire roof.
- [cert-3-label] SRI 107
- [cert-3-desc] High solar reflectance index for measurable passive cooling of the building interior.
- [cert-4-label] 20-year warranty
- [cert-4-desc] Anti-corrosion and cool roof covered by a two-decade manufacturer warranty.
- [cert-5-label] Low-VOC formulation
- [cert-5-desc] Meets the environmental requirements of high-performance buildings.
- [cert-6-label] Resin with 200% elongation
- [cert-6-desc] Elasticity that absorbs differential expansion between sheets without cracking.

## [advantages] Advantages

- [adv-eyebrow] Advantages
- [adv-title-line1] The advantages of the CovaMetal 20
- [adv-title-line2] steel deck cool roof coating.
- [adv-intro] Applying CovaMetal 20 to a corroded metal roof produces a triple effect from the very first season: corrosion is stopped, waterproofing is restored, and the indoor temperature drops measurably. Here are the six benefits observed on job sites.
- [adv-1-title] Corrosion stopped in a single application
- [adv-1-desc] Stops the spread of rust on affected sheets and protects sound metal from future air and moisture attack. 20-year warranty.
- [adv-2-title] Reinforced waterproofing at critical points
- [adv-2-desc] Elastic membrane with 200% elongation that seals sheet overlaps, fastening points and details. Durable rubber-like finish.
- [adv-3-title] Workplace well-being
- [adv-3-desc] Up to 8 to 10°C cooler indoors without air conditioning. A steel deck warehouse at 45°C drops to around 32°C.
- [adv-4-title] Lower electricity bills
- [adv-4-desc] Air conditioning use reduced by 15 to 40% depending on the activity. Average ROI of 14 months.
- [adv-5-title] Cost-effective alternative to replacement
- [adv-5-desc] €20 to €25/m² for a full treatment versus €80 to €120/m² for a steel deck replacement.
- [adv-6-title] No interruption to your operations
- [adv-6-desc] Spray application from the ground, machines at the foot of the building, only hoses on the roof. No load, no vibration, no risk to the structure.

## [comparison] Comparison

- [comp-eyebrow] Comparison
- [comp-title-line1] Steel deck cool roof coating or
- [comp-title-line2] full roof replacement?
- [comp-intro] The choice between CovaMetal 20 and a full steel deck replacement depends on the structural condition of the roof, the available budget, and the tolerance for business interruption. The criteria that matter are summarized below.
- [comp-col-a] CovaMetal 20
- [comp-col-a-badge] Recommended
- [comp-col-b] Steel deck replacement
- [comp-row-1-label] Cost per m²
- [comp-row-1-a] €20 to €25
- [comp-row-1-b] €80 to €120
- [comp-row-2-label] Project duration
- [comp-row-2-a] 3 to 5 days
- [comp-row-2-b] 3 to 8 weeks
- [comp-row-3-label] Cool roof effect
- [comp-row-3-a] up to 10°C cooler
- [comp-row-3-b] Depending on the color of the new sheets
- [comp-row-4-label] Anti-corrosion
- [comp-row-4-a] Active treatment over 20 years
- [comp-row-4-b] New sheets
- [comp-row-5-label] Waterproofing
- [comp-row-5-a] Continuous elastic film
- [comp-row-5-b] New joints
- [comp-row-6-label] Service life
- [comp-row-6-a] 20 years
- [comp-row-6-b] 25 to 40 years
- [comp-row-7-label] Business interruption
- [comp-row-7-a] No
- [comp-row-7-b] Yes
- [comp-row-8-label] Removal of existing roof
- [comp-row-8-a] No
- [comp-row-8-b] Yes
- [comp-row-9-label] Average ROI
- [comp-row-9-a] 14 months
- [comp-row-9-b] 8 to 15 years
- [comp-cta] Request a quote
- [comp-footer] CovaMetal 20 is the solution that pays for itself the fastest, with no removal and no business interruption. It stands out as the reference for industrial, logistics and agricultural buildings whose steel deck roof is corroded at the surface but still structurally usable. For a non-metal roof (bitumen, concrete, membrane), the CovaSeal 20 cool roof waterproofing coating is better suited.

## [faq] Frequently asked questions

- [faq-heading] Your questions about CovaMetal 20
- [faq-subhead] Don't see your question? Talk to an expert or request a quote.
- [faq-cta] Request a quote
- [faq-1-q] CovaMetal 20 or a full steel deck replacement: how to decide?
- [faq-1-a] A full steel deck replacement remains essential when the sheets are perforated, when the underlying insulation is compromised, or when the load-bearing structure itself is degraded. CovaMetal 20 takes over as soon as the roof is still structurally sound but shows surface corrosion, localized leaks at sheet overlaps, or worn joints. A technical assessment helps you decide between the two solutions based on the actual condition of your roof.
- [faq-2-q] Does CovaMetal 20 work on an already heavily rusted roof?
- [faq-2-a] Yes, provided the corrosion is superficial and the sheets remain structurally sound. Prior mechanical stripping of the most affected areas is always carried out, followed by an anti-corrosion treatment integrated into the Base Coat. For perforated or deeply corroded sheets, the affected elements are replaced before application.
- [faq-3-q] Does a roof treated with CovaMetal 20 increase heating consumption in winter?
- [faq-3-a] This is a legitimate concern, especially for a metal roof, which has a reputation for letting heat escape. In reality, metal is a poor insulator by nature: treated or not, a steel deck retains virtually no indoor heat in winter (it is the under-roof insulation that plays this role, not the coating). The cool roof effect of CovaMetal works mainly when the sun shines directly on the roof, that is, in summer, at a high angle of incidence. In winter, the low sun strikes mostly the vertical facades and rarely the horizontal roof: the seasonal penalty is therefore marginal, and largely offset by summer gains over a full year.
- [faq-4-q] Does the product hold on sheet overlaps and fastening points?
- [faq-4-a] Yes, and that is precisely its strength. The elastomeric resin with 200% elongation forms a rubber-like film that absorbs differential expansion between steel deck sheets. The sheet overlaps, which account for 80% of leaks on aging metal roofs, are sealed by a continuous layer. Fastening points, ridges and edges receive a reinforced treatment during application.
- [faq-5-q] How much CovaMetal 20 is needed for 1,000 m²?
- [faq-5-a] The complete system consists of a Base Coat applied at 400 to 800 g/m² depending on the level of corrosion of the substrate, plus an anti-UV Top Coat. For 1,000 m², the Base Coat range is therefore between 400 and 800 kg, to which the final Top Coat is added. Precise quantities are calculated in the quote, sheet by sheet, based on the actual condition of the roof.
- [faq-6-q] Can CovaMetal 20 be applied yourself, or is a professional applicator required?
- [faq-6-a] CovaMetal 20 should be applied by a professional applicator — your own contractor, or one we can help you select — even more so than our other products. Working on a metal roof poses three specific challenges: steel deck sheets become slippery as soon as they are wet or oxidized, sheet overlaps create sharp edges that damage protective equipment, and the load-bearing capacity of corroded sheets does not always support an operator's weight without dedicated walkways. Added to this is the quality of the prior mechanical stripping, which directly determines how well the anti-corrosion treatment holds over 20 years. To preserve the manufacturer warranty, have your contractor apply the coating following these metal-specific best practices. We support you and your installer with detailed application guidance and product specifications.
- [faq-7-q] What is the price of a steel deck cool roof coating per m²?
- [faq-7-a] A professionally installed steel deck cool roof coating typically costs between €20 and €25/m², all-inclusive: assessment, mechanical stripping of corroded areas, plus supply and application of the complete system. Three factors cause the final figure to vary: the level of corrosion of the substrate, the area to be treated (sliding scale beyond 2,000 m²), and the complexity of the roof (overlaps, ridges, drains, penetrations). Against a full steel deck replacement at €80-120/m², the case is clear-cut.
- [faq-8-q] What maintenance does a steel deck cool roof coating require?
- [faq-8-a] The anti-UV Top Coat of CovaMetal 20 has self-cleaning properties. We recommend an annual visit and a water rinse to remove particles and optimize solar reflection. No chemical products are needed. A visual inspection of overlaps and fastening points every 5 years helps detect any onset of residual corrosion early.

## [editorial] Editorial feature

- [edit-eyebrow] Feature
- [edit-title-line1] The cool roof coating for steel deck,
- [edit-title-line2] explained.
- [edit-intro] Steel deck cool roof coating, reflective anti-corrosion coating, corroded metal roof renovation: several names describe a family of products specially formulated to address the common defects of aging metal roofs. Used to renovate industrial steel deck buildings without replacing the sheets, this solution stands out as the most cost-effective when the roof shows surface corrosion and localized leaks but remains structurally sound.
- [edit-s1-title] The principle of a steel deck cool roof coating
- [edit-s1-intro] A cool roof coating for a metal roof combines three technical mechanisms on the same substrate:
- [edit-s1-bullet-1] Anti-corrosion protection: an anti-oxidation primer and an insulating resin that cut off the metal's contact with oxygen and moisture, which cause rust.
- [edit-s1-bullet-2] Solar reflectance: reflects up to 90% of solar radiation rather than letting it heat the roof. On a metal roof, this effect is particularly pronounced because metal is an excellent thermal conductor.
- [edit-s1-bullet-3] 200% elasticity: the elastomeric resin forms a film that absorbs differential expansion between steel deck sheets and seals the sheet overlaps, where 80% of leaks are concentrated.
- [edit-s1-outro] The anti-UV Top Coat completes the system. It protects the resin from ultraviolet rays, stabilizes the whiteness, and prevents chalking over twenty years.
- [edit-s2-title] The roofs CovaMetal 20 was designed for
- [edit-s2-intro] CovaMetal 20 is the steel deck cool roof coating suited to the following situations:
- [edit-s2-bullet-1] Superficial corrosion of the sheets, localized or extensive but not through-going
- [edit-s2-bullet-2] Worn sheet overlaps with micro-leaks
- [edit-s2-bullet-3] Oxidized fastening points (screws, rivets) that create infiltration points
- [edit-s2-bullet-4] Aging metal ridges and edges
- [edit-s2-bullet-5] Steel deck roofs more than 10 years old that overheat in summer
- [edit-s2-outro] For a structurally sound metal roof that needs only the cool roof effect, the pure cool roof coating CovaTherm may be sufficient. Conversely, for a perforated steel deck or a degraded load-bearing structure, a partial or full replacement remains necessary before application.
- [edit-s3-title] The budget for a steel deck cool roof coating per square meter
- [edit-s3-intro] A professionally installed steel deck cool roof coating typically costs between €20 and €25/m², all-inclusive: assessment, mechanical stripping of corroded areas, plus supply and application of the complete system. Three factors cause the final figure to vary:
- [edit-s3-bullet-1] The level of corrosion of the substrate, which determines the extent of the prior stripping and the localized reinforcements needed
- [edit-s3-bullet-2] The area to be treated, with a sliding scale beyond 2,000 m²
- [edit-s3-bullet-3] The complexity of the roof (overlaps, ridges, drains, penetrations)
- [edit-s3-compare-intro] Against the traditional alternative, the case is clear-cut:
- [edit-s3-compare-1] Full steel deck replacement: €80 to €120/m² with removal, plus the associated business shutdown
- [edit-s3-compare-2] CovaMetal 20 (3-in-1 cool roof coating): €20 to €25/m²
- [edit-s3-outro] CovaMetal 20 cuts the renovation budget by a factor of 4 to 5, with the cool roof effect and a twenty-year warranty as a bonus. You can estimate the savings of a steel deck cool roof coating on your building.
- [edit-s4-title] How a Covalba project unfolds
- [edit-s4-intro] A steel deck renovation unfolds in five controlled steps, carried out by a professional applicator you commission.
- [edit-s4-step-1] Technical assessment. A technician evaluates the condition of the sheets, locates the corrosion areas, identifies the sheet overlaps and fastening points to be reinforced, and checks the load-bearing capacity of the structure. A poorly assessed substrate means a coating that blisters or delivers neither anti-corrosion nor waterproofing.
- [edit-s4-step-2] Mechanical stripping. The corroded areas are mechanically brushed to remove loose rust and recover sound metal before treatment. The sound sheets are cleaned with a high-pressure washer.
- [edit-s4-step-3] Application of the anti-corrosion Base Coat. A first coat treats the metal in depth and blocks the progression of oxidation. The sheet overlaps and fastening points receive a localized reinforcement.
- [edit-s4-step-4] Application of the reflective elastomeric resin. The Base Coat is sprayed from the ground, at 400 to 800 g/m² depending on the level of corrosion and the roughness of the substrate. The machines stay at the foot of the building; only the hoses go up to the roof.
- [edit-s4-step-5] Application of the Top Coat. The anti-UV finish seals the system and guarantees reflectivity over two decades.
- [edit-s4-outro] Application is done in dry weather, between 10 and 35°C. A typical 1,000 m² project is completed in 3 to 5 days, with no interruption to the building's operations. The application should be entrusted to a professional applicator trained to work safely on metal roofs.
- [edit-s5-title] The protective effect of a reflective coating on a metal roof
- [edit-s5-p1] On a dark steel deck roof, the surface can exceed 70 to 80°C in midsummer. This heat accelerates the degradation of the sheets through three mechanisms: accelerated oxidation on contact with moisture (nighttime dew on hot metal), thermal expansion that unseals the sheet overlaps, and repeated expansion-contraction cycles that fatigue the fastening points. Scientific studies on the aging of roof coatings confirm that ultraviolet light and thermal cycles are the two main degradation factors, in a process strongly dependent on temperature (Miller, Kriner & Desjarlais, 2002).
- [edit-s5-p2] By lowering the surface temperature of the roof, the steel deck cool roof coating drastically limits these three factors. Field tests conducted by the Lawrence Berkeley National Laboratory measured a surface temperature drop from 79°C to 49°C after application of a reflective coating (Akbari, Berdahl, Levinson et al., 2005). Less heat absorbed means less differential expansion, fewer nighttime oxidation cycles, and a steel deck service life extended by 8 to 10 years.
- [edit-s6-title] A concrete lever against urban heat islands
- [edit-s6-p1] Beyond the direct benefits for the building, a steel deck cool roof coating helps reduce the urban heat island effect, the phenomenon whereby city centers and industrial zones are on average 2 to 10°C hotter than the surrounding rural areas. The dark metal roofs of warehouses and industrial buildings play a major role in this by massively absorbing solar radiation and releasing it as heat.
- [edit-s6-p2] Research on urban cooling strategies shows that widespread adoption of reflective roofs at a city scale could help reduce urban ambient temperature and, in turn, the energy demand for air conditioning (Santamouris, 2014). Research at the urban scale has even estimated that deploying cool roofs could reduce heatwave-related mortality by 18%. Applying CovaMetal 20 to an industrial or logistics steel deck building means contributing to this collective effort, on top of gaining indoor comfort.
- [edit-sources-title] Sources and references
- [edit-source-1] Akbari, H., Berdahl, P., Levinson, R., Wiel, S., Miller, W., & Desjarlais, A. (2005). Aging and Weathering of Cool Roofing Membranes. Lawrence Berkeley National Laboratory / U.S. Department of Energy.
- [edit-source-2] Santamouris, M. (2014). Cooling the cities — a review of reflective and green roof mitigation technologies to fight heat island and improve comfort in urban environments. Solar Energy, 103, 682-703.
- [edit-source-3] Synnefa, A., Santamouris, M., & Akbari, H. (2007). Estimating the effect of using cool coatings on energy loads and thermal comfort in residential buildings in various climatic conditions. Energy and Buildings, 39(11), 1167-1174.
- [edit-source-4] U.S. Environmental Protection Agency (2024). Using Cool Roofs to Reduce Heat Islands.

## [seo] SEO metadata

- [seo-title] Steel deck cool roof coating CovaMetal 20: 3-in-1, 20 years | Covalba
- [seo-description] CovaMetal 20, the 3-in-1 steel deck cool roof coating. Anti-corrosion, waterproofing and up to 10°C cooler indoors, 20-year warranty. By Covalba.
- [seo-product-name] Steel deck cool roof coating CovaMetal 20
- [seo-product-description] 3-in-1 cool roof coating for metal roofs: anti-corrosion, reinforced waterproofing and reflective effect, 20-year warranty. By Covalba.
- [seo-product-category] Steel deck cool roof coating
- [seo-breadcrumb-home] Home
- [seo-breadcrumb-solutions] Our solutions
- [seo-breadcrumb-product] CovaMetal 20