--- title: Polyureas vs Epoxies for Floor Control Joints description: Polyureas vs Epoxies for Floor Control Joints image: https://blogs.chemcosystems.com/hubfs/Imported_Blog_Media/polyurea%2c_cutting-2.jpg --- [Skip to content](https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints#main-content) [![logo](https://blogs.chemcosystems.com/hs-fs/hubfs/logo.png?width=314&height=54&name=logo.png "logo")](https://www.chemcosystems.com/) - Who We Are Show submenu for Who We Are - [About ChemCo Systems](https://www.chemcosystems.com/who-we-are.php) - [Projects](https://www.chemcosystems.com/projects.php) - What We Do Show submenu for What We Do - [Testing & Evaluation](https://www.chemcosystems.com/testing-and-evaluation.php) - [Application & Development](https://www.chemcosystems.com/application-and-development.php) - [Product Analysis](https://www.chemcosystems.com/product-analysis.php) - [Field Inspection](https://www.chemcosystems.com/field-inspection.php) - [Special Manufacturer (Private Label)](https://www.chemcosystems.com/special-manufacture.php) - What We Sell Show submenu for What We Sell - [Infrastructure/DOT](https://www.chemcosystems.com/landing.php?landingName=Infrastructure) - [Pavement Markings](https://www.chemcosystems.com/landing.php?landingName=PavementMarkings) - [Epoxy Asphalt](https://www.chemcosystems.com/landing.php?landingName=Epoxy%20Asphalt) - [Concrete Repair](https://www.chemcosystems.com/landing.php?landingName=ConcreteRepair) Show submenu for Concrete Repair - [CCS™](https://www.chemcosystems.com/landing.php?landingName=CCSProductCategories) - [Kemko®](https://www.chemcosystems.com/landing.php?landingName=Kemko) - [Cryogenic Insulation - InsulPOX](https://www.chemcosystems.com/cryogenic-insulation.php) - [Equipment and Parts](https://www.chemcosystems.com/equipment-parts.php) - [Blog](https://lp.chemcosystems.com/blog-home) - Tech Links Show submenu for Tech Links - [Structural Concrete Repair](https://www.chemcosystems.com/tech_strucrepair.php) - [Surface Prep](https://www.chemcosystems.com/tech_surfaceprep.php) - [Bonding-Old-to-New Concrete](https://www.chemcosystems.com/tech_bondingcon.php) - [Construction Polymers (Intro)](https://www.chemcosystems.com/tech_intropoly.php) - [Plate Bonding](https://www.chemcosystems.com/tech_platebond.php) - [Coating Guide](https://www.chemcosystems.com/tech_coatguide.php) - [CCS™ Equivalents](https://www.chemcosystems.com/pdf/tech_ccs_prod_equiv.pdf) - [Kemko® Equivalents](https://www.chemcosystems.com/pdf/tech_kemko_prod_equiv.pdf) - [Tech FAQs](https://www.chemcosystems.com/tech_faqs.php) - [Epoxy Asphalt FAQs](https://www.chemcosystems.com/epoxy-faq.php) - [Coating and Crack Quantity Calculator](https://www.chemcosystems.com/pdf/ccc.pdf) - [Contact](https://www.chemcosystems.com/contact-us.php) Open main navigation Close main navigation - Who We Are Show submenu for Who We Are - [About ChemCo Systems](https://www.chemcosystems.com/who-we-are.php) - [Projects](https://www.chemcosystems.com/projects.php) - What We Do Show submenu for What We Do - [Testing & Evaluation](https://www.chemcosystems.com/testing-and-evaluation.php) - [Application & Development](https://www.chemcosystems.com/application-and-development.php) - [Product Analysis](https://www.chemcosystems.com/product-analysis.php) - [Field Inspection](https://www.chemcosystems.com/field-inspection.php) - [Special Manufacturer (Private Label)](https://www.chemcosystems.com/special-manufacture.php) - What We Sell Show submenu for What We Sell - [Infrastructure/DOT](https://www.chemcosystems.com/landing.php?landingName=Infrastructure) - [Pavement Markings](https://www.chemcosystems.com/landing.php?landingName=PavementMarkings) - [Epoxy Asphalt](https://www.chemcosystems.com/landing.php?landingName=Epoxy%20Asphalt) - [Concrete Repair](https://www.chemcosystems.com/landing.php?landingName=ConcreteRepair) Show submenu for Concrete Repair - [CCS™](https://www.chemcosystems.com/landing.php?landingName=CCSProductCategories) - [Kemko®](https://www.chemcosystems.com/landing.php?landingName=Kemko) - [Cryogenic Insulation - InsulPOX](https://www.chemcosystems.com/cryogenic-insulation.php) - [Equipment and Parts](https://www.chemcosystems.com/equipment-parts.php) - [Blog](https://lp.chemcosystems.com/blog-home) - Tech Links Show submenu for Tech Links - [Structural Concrete Repair](https://www.chemcosystems.com/tech_strucrepair.php) - [Surface Prep](https://www.chemcosystems.com/tech_surfaceprep.php) - [Bonding-Old-to-New Concrete](https://www.chemcosystems.com/tech_bondingcon.php) - [Construction Polymers (Intro)](https://www.chemcosystems.com/tech_intropoly.php) - [Plate Bonding](https://www.chemcosystems.com/tech_platebond.php) - [Coating Guide](https://www.chemcosystems.com/tech_coatguide.php) - [CCS™ Equivalents](https://www.chemcosystems.com/pdf/tech_ccs_prod_equiv.pdf) - [Kemko® Equivalents](https://www.chemcosystems.com/pdf/tech_kemko_prod_equiv.pdf) - [Tech FAQs](https://www.chemcosystems.com/tech_faqs.php) - [Epoxy Asphalt FAQs](https://www.chemcosystems.com/epoxy-faq.php) - [Coating and Crack Quantity Calculator](https://www.chemcosystems.com/pdf/ccc.pdf) - [Contact](https://www.chemcosystems.com/contact-us.php) - [Quick Links](https://www.chemcosystems.com/quick_link.php) [Quick Links](https://www.chemcosystems.com/quick_link.php) Feb 2, 2024 12:00:00 AM # Polyureas vs Epoxies for Floor Control Joints [John Bors](https://blogs.chemcosystems.com/concrete-repair-posts/author/john-bors) Share: [facebook-f icon](http://www.facebook.com/share.php?u=https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints) [linkedin-in icon](http://www.linkedin.com/shareArticle?mini=true&url=https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints) [Twitter icon](https://twitter.com/intent/tweet?url=https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints) [pinterest-p icon](http://pinterest.com/pin/create/link/?url=https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints) [envelope icon](mailto:?body=https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints) **Polyureas *vs.* Epoxies ![polyurea,_cutting-2](https://blogs.chemcosystems.com/hs-fs/hubfs/Imported_Blog_Media/polyurea%2c_cutting-2.jpg?width=109&height=84&name=polyurea%2c_cutting-2.jpg)** Polyureas are now a popular choice for filling and repairing saw cut control joints and construction joints on commercial, industrial and warehouse floors, as well as some exterior areas where high heels or skate wheels cross joints. In the good old days before polyureas, semi-rigid epoxies were more widely used. Which product is better? At *[ChemCo Systems](http://www.chemcosystems.com),* we don’t have a favorite because we make a [selection](http://www.http://chemcosystems.com/ccs_grouts.html) of both products. To choose, consider the intended use of the facility substrate and the application environment. Control (construction) floor joints are filled for several reasons: a) protect the integrity of the joint (reduce joint nose spalling), b) safety, c) reduce maintenance costs and d) prevent accumulation of foreign debris. The optimal polymer choice may relate to the the type of traffic that uses the floor.         **Polyurea Control Joints** Cure speed is the most desirable feature as often the filled joint can often be opened to traffic within 1-2 hours or sooner. Since time is money and finishing the floor is one of the last steps prior to opening, the faster cure speed of the polyurea is often the most valuable benefit.              Because of very fast gel times, it is may be impractical to hand-mix the faster curing polyureas, so using a special pump such as our **[Model C](http://www.http://chemcosystems.com/equipment_model_c.html)** may be useful on very large jobs for high production rates.              ![polyswl,web-1](https://blogs.chemcosystems.com/hs-fs/hubfs/Imported_Blog_Media/polyswl%2cweb-1.jpg?width=252&height=162&name=polyswl%2cweb-1.jpg) Unlike epoxies, polyureas can cure in very cold conditions, in some cases as low as -25°F. In fact, polyureas are used frequently to fill joints in large freezer (and refrigerator) warehouse floors while the freezer is in service. At this low temperature, an epoxy is dormant and will likely freeze. Usually, an epoxy will cure when the ambient air increases to 40°F or more.               [Polyureas](https://www.chemcosystems.com/wp-content/uploads/2017/11/Binder_Polyurea_SWL.pdf) are often touted for their greater elongation capability (up to 200%+ vs. ~90% for epoxies). Yet neither polyureas or epoxies are intended for use in joints designed to move (such as expansion joints). The tall proportional cross-section (height vs width) of most control joints causes either polymer material to separate from the side wall if there is significant joint movement because neither can stretch across its thick middle. Though polyureas are generally softer, they are generally very tough under abrasive or mechanical shock conditions. Tested in a standard Taber test rig, they may exhibit 40% less weight loss after 1000 cycles than control joint epoxies.               A cautionary note—always use an epoxy primer such as [QuikPrime](https://www.chemcosystems.com/wp-content/uploads/2017/11/QuikPrime.pdf) with a polyurea when in doubt about dampness or moisture in the joint. The isocyanate portion of a polyurea reacts very quickly with moisture and this interaction may decrease the performance of the cured polymer or cause gassing or foaming. Moisture is a more common issue with older slab on grade floors that did not have an underlying impermeable membrane liner installed prior to the pour. **Epoxy Control Joints**  ![exterior control joint epoxy-Jan-30-2024-08-54-18-7383-PM](https://blogs.chemcosystems.com/hs-fs/hubfs/Imported_Blog_Media/exterior%20control%20joint%20epoxy-Jan-30-2024-08-54-18-7383-PM.jpg?width=155&height=252&name=exterior%20control%20joint%20epoxy-Jan-30-2024-08-54-18-7383-PM.jpg)Although generally slower curing, this may be an advantage if the crack filling is done by hand pouring or a bulk caulk gun because of longer working time.               When the substrate is damp, wet, or contaminated, an unprimed epoxy has a better chance of bonding to the sides of the joint than a high speed polyurea.               In exterior applications, UV exposure causes fading and sometimes chalking of an epoxy. With aromatic-type polyureas often used in control joints, there can be significant color changes caused by sunlight which may be cosmetically unappealing.               When it comes to mixing and tolerance for “eye-balling” the proportions of A & B components, epoxies are more forgiving. Polyureas may lose some of their properties as soon as the mix ratio is off by 3-6% or more, whereas epoxies will often cure when the proportions are even further apart. Additionally, epoxies tend to be more forgiving if mixing shear is marginal.               Most [semi-rigid epoxies](https://www.chemcosystems.com/wp-content/uploads/2017/11/Grout_Control_Joint.pdf) are harder (higher durometer) than comparable polyureas. This may be a critical factor in uses when there is high point loading across floor joints such as the steel wheels on some pallet jacks.  Epoxies are generally better performers if there is a suspected moisture issue on the substrate during the application of the joint filler. The polymerization between the A and B component of the epoxy joint filler is not interfered with by minor amounts of moisture. However, if the walls of the joint are wet, then a fast setting underwater primer, such as [QuikPrime](https://www.chemcosystems.com/wp-content/uploads/2017/11/QuikPrime.pdf), should be used to pretreat the joint walls.             Both product types are relatively chemical resistant, but the epoxy usually has an edge with organic solvents, many acids and some oxidizers and sanitizers commonly used on floors such as bleaches. Both products can be blended (extended) with carefully selected and sized aggregates or natural sands for deep or high volume repairs. Please call to ask for our help if this option is of interest. It's most important to use only dried sands containing less than 0.2% moisture by weight for either binder. Joint filling with either epoxy or polyurea should be deferred as long as possible after concrete floor is poured to allow for minimal additional slab shrinkage, based on ACI 302.1R recommendations.  Consult ACI 302.1R comments regarding concrete shrinkage, joint filling, and user expectations. If you need more help, call us (800-757-6773, 650-261-3790) for friendly technical assistance and the best selection anywhere. We're usually in the office by 6:30 and out by 5:00 California time. Or send an email to info1@chemcosystems.com. [floor joint filler](https://blogs.chemcosystems.com/concrete-repair-posts/tag/floor-joint-filler), [semi rigid control joint filler](https://blogs.chemcosystems.com/concrete-repair-posts/tag/semi-rigid-control-joint-filler), [construction joint filler](https://blogs.chemcosystems.com/concrete-repair-posts/tag/construction-joint-filler), [concrete joint repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-joint-repair), [fast set polyurea](https://blogs.chemcosystems.com/concrete-repair-posts/tag/fast-set-polyurea), [control joint filler](https://blogs.chemcosystems.com/concrete-repair-posts/tag/control-joint-filler), [grouting concrete saw cuts](https://blogs.chemcosystems.com/concrete-repair-posts/tag/grouting-concrete-saw-cuts), [semi-rigid epoxy joint filler](https://blogs.chemcosystems.com/concrete-repair-posts/tag/semi-rigid-epoxy-joint-filler), [rapid cure polyurea](https://blogs.chemcosystems.com/concrete-repair-posts/tag/rapid-cure-polyurea), [filling saw cuts in concrete slab](https://blogs.chemcosystems.com/concrete-repair-posts/tag/filling-saw-cuts-in-concrete-slab), [floor joint repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/floor-joint-repair) ## Related posts [![](https://blogs.chemcosystems.com/hs-fs/hubfs/Imported_Blog_Media/lemoore-Jan-30-2024-06-47-46-1013-PM.jpg?height=200&name=lemoore-Jan-30-2024-06-47-46-1013-PM.jpg)](https://blogs.chemcosystems.com/concrete-repair-posts/blog/baby-carrots-and-fighter-jetshs_amptrue) [flexible polymer concrete](https://blogs.chemcosystems.com/concrete-repair-posts/tag/flexible-polymer-concrete), [low modulus epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/low-modulus-epoxy), [concrete spall repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-spall-repair), [low mod epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/low-mod-epoxy), [concrete joint repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-joint-repair), [flexible epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/flexible-epoxy), [news](https://blogs.chemcosystems.com/concrete-repair-posts/tag/news), [bonding flexible material to concrete](https://blogs.chemcosystems.com/concrete-repair-posts/tag/bonding-flexible-material-to-concrete), [toughened epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/toughened-epoxy), [concrete patch](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-patch) ## [Baby Carrots and Fighter Jets use Lo-Mod Epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/blog/baby-carrots-and-fighter-jetshs_amptrue) [John Bors](https://blogs.chemcosystems.com/concrete-repair-posts/author/john-bors) Feb 2, 2024 12:00:00 AM What do F-16's, F-18's and baby carrots have in common? They have all landed on CCS Patch, Nosing,... [Read more](https://blogs.chemcosystems.com/concrete-repair-posts/blog/baby-carrots-and-fighter-jetshs_amptrue) [![](https://blogs.chemcosystems.com/hs-fs/hubfs/Imported_Blog_Media/12-Jan-30-2024-07-47-01-4594-PM.jpg?height=200&name=12-Jan-30-2024-07-47-01-4594-PM.jpg)](https://blogs.chemcosystems.com/concrete-repair-posts/25-incredible-concrete-repair-tips-for-pros-using-epoxy) [epoxy injection](https://blogs.chemcosystems.com/concrete-repair-posts/tag/epoxy-injection), [epoxy limitations](https://blogs.chemcosystems.com/concrete-repair-posts/tag/epoxy-limitations), [concrete spall repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-spall-repair), [structural repair epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/structural-repair-epoxy), [concrete repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-repair), [epoxy repair tips](https://blogs.chemcosystems.com/concrete-repair-posts/tag/epoxy-repair-tips), [concrete crack repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-crack-repair), [mixing and measuring epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/mixing-and-measuring-epoxy) ## [25 Incredible Concrete Repair Tips for Pros using Epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/25-incredible-concrete-repair-tips-for-pros-using-epoxy) [John Bors](https://blogs.chemcosystems.com/concrete-repair-posts/author/john-bors) Feb 2, 2024 12:00:00 AM Surface prep is vital As in many other construction activities, taking proper steps to properly... [Read more](https://blogs.chemcosystems.com/concrete-repair-posts/25-incredible-concrete-repair-tips-for-pros-using-epoxy) [![](https://blogs.chemcosystems.com/hs-fs/hubfs/concrete_crack_repair1-jpg.jpeg?height=200&name=concrete_crack_repair1-jpg.jpeg)](https://blogs.chemcosystems.com/concrete-repair-posts/when-do-you-need-a-professional-for-concrete-crack-repair) [epoxy injection](https://blogs.chemcosystems.com/concrete-repair-posts/tag/epoxy-injection), [concrete crack repair](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-crack-repair), [concrete repair epoxy](https://blogs.chemcosystems.com/concrete-repair-posts/tag/concrete-repair-epoxy) ## [When do you need a professional for Concrete Crack Repair?](https://blogs.chemcosystems.com/concrete-repair-posts/when-do-you-need-a-professional-for-concrete-crack-repair) [John Bors](https://blogs.chemcosystems.com/concrete-repair-posts/author/john-bors) Feb 2, 2024 12:00:00 AM Concrete cracks. It’s a fact of life. Some cracks might not need attention while others could have... [Read more](https://blogs.chemcosystems.com/concrete-repair-posts/when-do-you-need-a-professional-for-concrete-crack-repair) ![logo](https://blogs.chemcosystems.com/hs-fs/hubfs/logo.png?width=305&height=52&name=logo.png "logo")   Professional products and training programs for concrete repair, concrete bonding, concrete restoration, concrete coatings and concrete protection including epoxy injection and metering pumps for structural concrete crack repair and control joint fillers in civil engineering, government, commercial, industrial and mro applications. Our epoxy adhesives and coatings are 0 VOC and offer LEED credits including IEQ 4.1, meet ASTM C 881 Types I, II, III, IV, V, VI and VII and fully comply with the Buy America Act for U.S. transportation projects using federal funding. #### Contact --- ###### Call for a quote 650-261-3790 ## Address 2800 Bay Road Redwood City, CA 94063 #### Quick Links --- | [Infrastructure/DOT](https://www.chemcosystems.com/landing.php?landingName=Infrastructure) [Pavement Markings](https://www.chemcosystems.com/landing.php?landingName=PavementMarkings) [Epoxy Asphalt](https://www.chemcosystems.com/landing.php?landingName=Epoxy%20Asphalt) [Concrete Repair](https://www.chemcosystems.com/landing.php?landingName=ConcreteRepair) [Cryogenic Insulation - InsulPOX®](https://www.chemcosystems.com/cryogenic-insulation.php) | [Who We Are](https://www.chemcosystems.com/who-we-are.php) [Equipment & Parts](https://www.chemcosystems.com/equipment-parts.php) [Blogs](https://lp.chemcosystems.com/blog-home) [Contact](https://www.chemcosystems.com/contact-us.php) [Quick Links](https://www.chemcosystems.com/quick_link.php) | | --- | --- |   ```json { "@context" : "https://schema.org", "@type" : "BlogPosting", "author" : { "@type" : "Person", "name" : "John Bors", "url" : "https://blogs.chemcosystems.com/concrete-repair-posts/author/john-bors" }, "dateModified" : "2024-04-10T22:14:21.216Z", "datePublished" : "2024-02-02T08:00:00.000Z", "headline" : "Polyureas vs Epoxies for Floor Control Joints", "image" : [ "https://blogs.chemcosystems.com/hubfs/Imported_Blog_Media/polyurea%2c_cutting-2.jpg" ], "mainEntityOfPage" : { "@id" : "https://blogs.chemcosystems.com/concrete-repair-posts/polyureas-vs-epoxies-for-floor-control-joints", "@type" : "WebPage" }, "publisher" : { "@type" : "Organization", "logo" : { "@type" : "ImageObject", "url" : "https://blogs.chemcosystems.com/hubfs/ChemCo-Logo-2.png" }, "name" : "Polycoat USA" } } ```