diff --git a/src/components/structures/RoomSubList.js b/src/components/structures/RoomSubList.js
index e1bc1954da..e00f0f2d03 100644
--- a/src/components/structures/RoomSubList.js
+++ b/src/components/structures/RoomSubList.js
@@ -350,7 +350,7 @@ const RoomSubList = React.createClass({
             } else {
                 const heightEstimation = (len * 40) + 31;
                 const style = {
-                    flexBasis: `${heightEstimation}px`,
+                    flexGrow: `${heightEstimation}`,
                     maxHeight: `${heightEstimation}px`,
                 };
                 const GeminiScrollbarWrapper = sdk.getComponent("elements.GeminiScrollbarWrapper");