{"id":507,"date":"2026-09-23T13:47:37","date_gmt":"2026-09-23T05:47:37","guid":{"rendered":"http:\/\/www.jsbudea.com\/blog\/?p=507"},"modified":"2026-09-23T13:47:37","modified_gmt":"2026-09-23T05:47:37","slug":"what-are-the-color-fastness-properties-of-co-extrusion-cladding-42b9-92591a","status":"publish","type":"post","link":"http:\/\/www.jsbudea.com\/blog\/2026\/09\/23\/what-are-the-color-fastness-properties-of-co-extrusion-cladding-42b9-92591a\/","title":{"rendered":"What are the color fastness properties of CO – Extrusion Cladding?"},"content":{"rendered":"

Hey everyone, it\u2019s Mia from the cladding team\u2014let\u2019s cut right to the chase because if you\u2019re dealing with exterior building materials, one thing that makes or breaks your project is color holding up, right? Last month we had an architect hit me up panicking because their old composite cladding was faded so bad after 2 years, they had to rip half of it off their mixed-use building. That\u2019s the kind of headache we built our CO-extrusion cladding to avoid, so today I wanna break down the color fastness of our product\u2014no jargon, just real talk about what it means for your jobs, how we test it, and why it\u2019s not the same as that cheaper stuff you might be looking at. CO-Extrusion Cladding<\/a><\/p>\n

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First off, let\u2019s get one thing straight: color fastness isn\u2019t just \u201cdoes the color stay pretty?\u201d It\u2019s how it holds up against the four big environmental bullies: UV rays, rain, temperature swings, and pollution. For CO-extrusion cladding specifically, the way we make it is a huge difference-maker. If you\u2019re new to the process, CO-extrusion means we melt two separate polymer layers (usually PVC, but we also do co-ex with HDPE for some projects) and fuse them together while they\u2019re still molten\u2014no glues, no adhesives, just molecular bonding. That outer layer isn\u2019t a thin paint or a thin wrap we slap on after; it\u2019s a full, fused layer all the way through the outer part of the cladding. No peeling, no chipping, and way less chance of the color wearing off from the surface.<\/p>\n

Now, let\u2019s talk about UV fastness, because that\u2019s the big one for anyone in places with intense sun\u2014like the Southwestern US, Mediterranean, Southeast Asia, anywhere that\u2019s not super cloudy 24\/7. Most lower-quality cladding uses a \u201ccoated over\u201d system, where they spray or roll on a color coating after the base cladding is extruded. That coating might be a basic pigment mixed with some UV stabilizers, but it\u2019s sitting on top of the plastic, so over time, UV radiation breaks down that coating\u2019s molecular structure, making it fade, chalk (that powdery residue you get when the surface breaks down), or peel right off. Our CO-extrusion process? We mix UV stabilizers and fade-resistant pigments directly into that outer extruded layer<\/em> before we fuse it to the base. We use pigments that are specifically formulated for exterior polymers\u2014no cheap indoor pigments here. I can throw up a quick example: our standard gray cladding is a carbon-black-based pigment mixed with 3% of our custom UV stabilizer blend, and our test data shows it holds up 2x longer than a coated PVC cladding we tested against last year. Wait, but don\u2019t take my word for it\u2014we do actual accelerated weathering tests, not just lab nonsense.<\/p>\n

Accelerated weathering testing is basically the industry way to simulate years of sun and rain in a few weeks. We use a QUV chamber, which blasts UV light at a specific intensity and cycles in condensation to mimic rain and dew. For our CO-extrusion cladding, we run those tests for 3,000, 5,000, even 8,000 hours. The ISO standard for exterior building cladding is usually around 1,000 hours of QUV exposure with a delta E (that\u2019s the color difference number\u2014lower is better) of less than 2. What\u2019s delta E? It\u2019s a numerical score that measures how much two colors differ; anything under 2 is basically undetectable to the human eye, and we hit that delta E mark at 5,000 hours, and most of our custom color runs barely top delta E 1 at 5,000 hours. Last quarter we had a commercial project in Phoenix, AZ that\u2019s been using our medium-brown CO-extrusion cladding for 3 years now\u2014they sent us a photo last week, and a quick color check against the sample we sent them showed delta E 0.8. That\u2019s insane, right? For comparison, the coated cladding they used on a different building by the same team had a delta E of 4.2 after the same 3 years.<\/p>\n

But color fastness isn\u2019t just UV\u2014there\u2019s also water fastness, which is how the color holds up to rain, humidity, standing water, even things like snowmelt that might have road salt or other chemicals in it. With CO-extrusion, since the outer layer is fused to the base, there\u2019s no gap or weak point between the two layers where water can get in and wash out pigments. Coated cladding has a seam between the coating and the base, so over time, water seeps in, breaks down the coating, and causes blistering or discoloration. We tested our CO-extrusion cladding in a 1,000-hour water immersion test, submerging samples in both regular tap water and slightly alkaline water (to mimic hard water in places like Texas) and we saw zero color shift, no blistering, no pigment leaching. We also had a project in Florida, where salt air is brutal on building materials\u2014our coastal CO-extrusion cladding samples, which have an extra anti-corrosion additive in the outer layer, have held up perfectly for 2 years, no salt-related discoloration. That\u2019s a big deal because salt air eats away at any weak coating layer way faster than regular rain.<\/p>\n

Another thing people sleep on is heat and cold fastness. If you\u2019re in a place that goes from 100\u00b0F+ in summer to 10\u00b0F or lower in winter, that temperature swing can cause materials to expand and contract, which is a problem if your color layer is just sitting on top. Coated cladding will often crack or peel when the plastic expands and contracts unevenly, exposing the faded base layer. Our CO-extrusion layers are fused together, so they expand and contract as one single material\u2014no separation, no cracking, no peeling of the color layer. We tested that by putting samples through 100 thermal cycles, going from -40\u00b0F to 140\u00b0F each cycle, which is way more extreme than almost any project will see, and the delta E after that was still under 1.5. The coated sample we tested? It had a delta E of 5.8, plus tiny cracks in the coating that you could see under a magnifying glass. That\u2019s the kind of thing you don\u2019t notice for a year, but by year 3, it\u2019s a big enough deal that you have to replace panels.<\/p>\n

Now, let\u2019s be real\u2014there are some caveats here, because no product is perfect, and I don\u2019t wanna oversell this. First, color selection matters. We can\u2019t make neon colors, or super vibrant hues, that are never gonna be fade-resistant, because pigments that are that bright don\u2019t hold up well to UV. We have a range of standard colors that are tested and proven, and we can do custom colors if you\u2019re okay with a slightly longer lead time\u2014we just don\u2019t guarantee neon or super-saturated colors for projects where color fastness is the top priority. Second, installation matters. If you install the cladding wrong, like not leaving the proper expansion gaps, or letting water pool behind the panels, even the best color fastness won\u2019t save it. We always send an installation guide with every order, and our team is always here to help walk your installer through it if they have questions. Third, maintenance is basic\u2014just wash the panels once a year with mild soap and water, don\u2019t use pressure washers on the highest setting because that can scratch the surface (scratches might look like discoloration, but they\u2019re just surface marks, not actual fading).<\/p>\n

I know a lot of suppliers will tell you their cladding is \u201c100% fade-proof\u201d and throw out vague numbers like \u201c10 year warranty\u201d without backing it up. We do a 15-year limited warranty on all our CO-extrusion cladding related to color fastness\u2014meaning if the delta E goes over 2 in that time, we\u2019ll replace the panels for free. That\u2019s not something we can do with coated cladding, because most coated cladding only has a 3-5 year warranty for color, if that. Last year we had a residential project in Colorado that had a custom gray color with a slight blue tint, and after 4 years, the home owner noticed a tiny amount of fade (delta E 2.1, which is just barely over our threshold). We sent a full set of replacement panels at no cost, no questions asked. That\u2019s the kind of accountability you don\u2019t get from the cheaper suppliers.<\/p>\n

Wait, also, a lot of people confuse color fastness with color uniformity\u2014like, do all the panels come out the same color? That\u2019s part of CO-extrusion too. Since we mix the color pigments directly into the outer layer during extrusion, every panel is the same from end to end, no variation in the surface that you get with coated cladding, which can have slight color shifts between batches. We measure every batch with a spectrophotometer to make sure the delta E between any two panels is under 0.5, so when you put up a whole facade, it looks consistent, not patchy. That\u2019s huge for architects and contractors who need a seamless look for a project.<\/p>\n

Let me wrap this up with something practical, because I know you\u2019re here for your projects, not just lab talk. If you\u2019re working on a commercial building, a residential development in a sunny climate, or anything that needs to look good long-term without huge maintenance, our CO-extrusion cladding\u2019s color fastness is one of our biggest selling points. We\u2019ve done projects for office parks, apartment complexes, retail stores, even universities, and every single one has come back with positive feedback about how the color hasn\u2019t faded at all, even after 5+ years. If you\u2019re tired of dealing with faded cladding that needs replacement every few years, or you\u2019re tired of arguing with suppliers who don\u2019t back up their claims, reach out to our team to talk through your project, get sample panels, and we can give you a custom quote that fits your budget and timeline.<\/p>\n

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Don\u2019t settle for coated cladding that\u2019s gonna look worn out in 3 years. CO-extrusion is the future of exterior cladding, and the color fastness is why.<\/p>\n

WPC Cladding<\/a> References<\/p>\n

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  1. American Society for Testing and Materials (ASTM) D4587, Standard Practice for Fluorescent UV-Condensation Exposures of Building Materials<\/li>\n
  2. International Organization for Standardization (ISO) 105-B02, Textiles – Tests for colour fastness – Part B02: Colour fastness to artificial light: Xenon arc fading lamp test<\/li>\n
  3. Plastics Europe. (2021). Extruded Polymer Cladding for Outdoor Applications: Performance Properties and Durability Standards. Brussels, Belgium: Plastics Europe Association.<\/li>\n
  4. Q-Lab Corporation. (2022). Accelerated Weathering of Building Materials: Practical Guide to Testing and Performance. Cleveland, OH: Q-Lab Corporation.<\/li>\n<\/ol>\n
    \n

    Zhejiang Timber Biology New Material Co., Ltd.<\/a>
    As one of the most professional co-extrusion cladding manufacturers and suppliers in China, we’re featured by quality products and good service. Please rest assured to wholesale custom made co-extrusion cladding at competitive price from our factory.
    Address: No. 192, Longshan Road, Zhongguan Town, Deqing County, Huzhou City, Zhejiang Province
    E-mail: info@tongrui.cc
    WebSite:     https:\/\/www.utimberwpc.com\/<\/a><\/p>\n","protected":false},"excerpt":{"rendered":"

    Hey everyone, it\u2019s Mia from the cladding team\u2014let\u2019s cut right to the chase because if you\u2019re … What are the color fastness properties of CO – Extrusion Cladding?<\/span>Read more<\/a><\/p>\n","protected":false},"author":5,"featured_media":507,"comment_status":"closed","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1],"tags":[470],"class_list":["post-507","post","type-post","status-publish","format-standard","has-post-thumbnail","hentry","category-industry","tag-co-extrusion-cladding-4734-92bfb2"],"_links":{"self":[{"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/posts\/507","targetHints":{"allow":["GET"]}}],"collection":[{"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/users\/5"}],"replies":[{"embeddable":true,"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/comments?post=507"}],"version-history":[{"count":0,"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/posts\/507\/revisions"}],"wp:featuredmedia":[{"embeddable":true,"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/posts\/507"}],"wp:attachment":[{"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/media?parent=507"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/categories?post=507"},{"taxonomy":"post_tag","embeddable":true,"href":"http:\/\/www.jsbudea.com\/blog\/wp-json\/wp\/v2\/tags?post=507"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}