--- title: Why has the flooring/coating have patchy spots when it has dried? (Patchiness) description: Diagnosis, Causes and Solution to the undried, patchy, patchiness, uneven imperfection issues in epoxy resin coating/flooring --- [Skip to content](https://help.resincoat.co.uk/why-has-the-flooring/coating-have-patchy-spots-when-it-has-dried-patchiness#main-content) - [English](https://help.resincoat.co.uk/why-has-the-flooring/coating-have-patchy-spots-when-it-has-dried-patchiness) - [Deutsch](https://help.resincoat.co.uk/de/warum-weist-der-bodenbelag/die-beschichtung-nach-dem-trocknen-fleckige-stellen-auf-fleckigkeit) English Show submenu for translations Open main navigation Close main navigation - - [English](https://help.resincoat.co.uk/why-has-the-flooring/coating-have-patchy-spots-when-it-has-dried-patchiness) - [Deutsch](https://help.resincoat.co.uk/de/warum-weist-der-bodenbelag/die-beschichtung-nach-dem-trocknen-fleckige-stellen-auf-fleckigkeit) English Show submenu for translations - [Back to resincoat.co.uk](https://www.resincoat.co.uk/) [Back to resincoat.co.uk](https://www.resincoat.co.uk/) How Can We Help? - There are no suggestions because the search field is empty. 1. [Resincoat Info Hub](https://help.resincoat.co.uk/?hsLang=en) 2. [FAQ](https://help.resincoat.co.uk/faq?hsLang=en) 3. [Potential Issues (and Solutions!)](https://help.resincoat.co.uk/faq?hsLang=en#potential-issues-and-solutions) # Why has the flooring/coating have patchy spots when it has dried? (Patchiness) ### **What is it?** This is a standard patchy-coating issue, often identified by uneven areas across the surface of the coating. ![Patchiness](https://help.resincoat.co.uk/hs-fs/hubfs/Patchiness.jpg?width=688&height=688&name=Patchiness.jpg) ### **Common Causes:** **Lack of priming –** Whilst a primer isn’t always 100% necessary, it is 100% advised. By priming, you saturate the substrate which reduces the risk of further coats soaking in. The problem with not priming is that your first coat, or even possibly two coats, may soak into the substrate causing a very patchy surface. **Inadequate mixing –** This is more common in anti-slipped units of paint, where the anti-slip additive has not been correctly dispersed. This will cause concentrated patches of additive (dark patches) and areas without any additive at all (light patches), this is common if poured from tin to scuttle where the additive settles towards the bottom of the scuttle when not mixed thoroughly. **Substrate –** A poor or highly absorbent substrate can often lead to a patchy surface, this is why we always recommend grinding the floor prior to application or, if mechanical grinding isn’t an option, we recommend using our [Etch'N'Clean](https://www.resincoat.co.uk/en/concrete-repair-primers/447-etch-and-clean.html) acid etcher (however, this is only suitable for uncoated surfaces.). **Moisture –** If water meets the surface during curing, this may result in a patchy finish. ### **So, how would I resolve this?** - You can simply apply a further coat of product, please note: if your floor is particularly porous, you may need two further coats. - If the previous coating has been down for more than 48 hours, you will need to gently abrade the surface via sanding (Fine\>Medium grit). - Ensure the area is thoroughly cleaned to remove all debris. - Once sanded and cleaned, you can then apply your next coat. 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