diff --git a/panels_ipe/panels_ipe.api.php b/panels_ipe/panels_ipe.api.php
index bda971b..62550f3 100644
--- a/panels_ipe/panels_ipe.api.php
+++ b/panels_ipe/panels_ipe.api.php
@@ -41,3 +41,20 @@ function hook_panels_ipe_blocks_alter(array &$blocks = array()) {
     }
   }
 }
+
+/**
+ * Modify the list of layouts available through the IPE interface.
+ *
+ * @param array $layouts
+ *   The layouts that are currently available.
+ * @param \Drupal\panels\Plugin\DisplayVariant\PanelsDisplayVariant $panels_display
+ *   The current Panels display.
+ */
+function hook_panels_ipe_layouts_alter(array &$layouts, PanelsDisplayVariant $panels_display) {
+  // Only show layouts that are in the 'threecol' category.
+  foreach ($layouts as $key => $layout) {
+    if ($layout['category'] !== 'threecol') {
+      unset($layout[$key]);
+    }
+  }
+}
diff --git a/panels_ipe/src/Controller/PanelsIPEPageController.php b/panels_ipe/src/Controller/PanelsIPEPageController.php
index b8c2e4c..6825c5c 100644
--- a/panels_ipe/src/Controller/PanelsIPEPageController.php
+++ b/panels_ipe/src/Controller/PanelsIPEPageController.php
@@ -180,6 +180,14 @@ class PanelsIPEPageController extends ControllerBase {
       ];
     }
 
+    // Trigger hook_panels_ipe_layouts_alter(). Allows other modules to change
+    // the list of layouts that are visible.
+    \Drupal::moduleHandler()->alter('panels_ipe_layouts', $data, $panels_display);
+
+    // Reindex the blocks after they were altered in case one of them was
+    // removed.
+    $data = array_values($data);
+
     return $data;
   }