diff --git a/src/components/structures/RoomSubList.js b/src/components/structures/RoomSubList.js
index 2ae2d71100..1e3e15b4ec 100644
--- a/src/components/structures/RoomSubList.js
+++ b/src/components/structures/RoomSubList.js
@@ -32,6 +32,7 @@ import RoomTile from "../views/rooms/RoomTile";
 import LazyRenderList from "../views/elements/LazyRenderList";
 import {_t} from "../../languageHandler";
 import {RovingTabIndexWrapper} from "../../accessibility/RovingTabIndex";
+import toRem from "../../utils/rem";
 
 // turn this on for drop & drag console debugging galore
 const debug = false;
@@ -383,7 +384,7 @@ export default class RoomSubList extends React.PureComponent {
 
     setHeight = (height) => {
         if (this._subList.current) {
-            this._subList.current.style.height = `${height}px`;
+            this._subList.current.style.height = toRem(height);
         }
         this._updateLazyRenderHeight(height);
     };