--- title: Why does my flooring have water streaks/patchy coating? (Moisture Contamination) description: Diagnosis, Causes and Solution to the moisture contamination, streaks and patchy imperfection issues in epoxy resin coating/flooring --- [Skip to content](https://help.resincoat.co.uk/why-does-my-flooring-have-water-streaks/patchy-coating-moisture-contamination#main-content) - [English](https://help.resincoat.co.uk/why-does-my-flooring-have-water-streaks/patchy-coating-moisture-contamination) - [Deutsch](https://help.resincoat.co.uk/de/warum-weist-mein-boden-wasserstreifen-oder-eine-fleckige-beschichtung-auf-feuchtigkeitskontamination) English Show submenu for translations Open main navigation Close main navigation - - [English](https://help.resincoat.co.uk/why-does-my-flooring-have-water-streaks/patchy-coating-moisture-contamination) - [Deutsch](https://help.resincoat.co.uk/de/warum-weist-mein-boden-wasserstreifen-oder-eine-fleckige-beschichtung-auf-feuchtigkeitskontamination) 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. 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(Moisture Contamination) ### **What is it?** This appears to be a moisture contamination issue, various identifiers that primarily include water streaks, patchy coatings, and uncured epoxy. ![Moisture Contamination-1](https://help.resincoat.co.uk/hs-fs/hubfs/Moisture%20Contamination-1.jpg?width=688&height=356&name=Moisture%20Contamination-1.jpg) ### **Common Causes:** **Direct water** – A cured epoxy resin system forms a solid plastic like material, if water comes in to contact with the epoxy during its curing phase, a variety of problems can occur, the main issues being an uncured or patchy floor. **Condensation** – The general cause of this is space heaters, we don’t recommend the use of these as they often cause condensation to form, contaminating the coating as above. The other cause tends to be air con/underfloor heating, which we do not recommend using during the curing phase. **Rising Damp** – If no damp proof membrane is installed, or if a damp proof membrane has failed, you may find that rising damp will cause effects such as [delamination](https://7698278.hs-sites.com/knowledge/why-is-the-flooring/coating-peeling-away-peeling-delaminating?hsLang=en) (coating lifting completely), or cause water to rise through the coating causing other adverse effects. ### **So, how would I resolve this?** **Direct Water/Condensation** - If the product has not cured, it is recommended that you scrape out as much of the uncured product as possible, you can use a suitable solvent to clean your tools. - Once as much of the product has been removed as possible, give the area good clean ensuring that the area is free of any debris and moisture before applying further coatings. - If the product has cured, you would need to sand the surface, ensuring the sanding has created a white/hazy surface. - Once this has been done, ensure any debris is removed by vacuuming before recoating. **Rising Damp** Unfortunately, there is no easy fix for rising damp as this is often the result of a failed damp proof membrane, or no damp proof membrane at all. 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