diff --git a/data/api/client-server/definitions/public_rooms_chunk.yaml b/data/api/client-server/definitions/public_rooms_chunk.yaml
index d2e9a09b..89e76059 100644
--- a/data/api/client-server/definitions/public_rooms_chunk.yaml
+++ b/data/api/client-server/definitions/public_rooms_chunk.yaml
@@ -61,7 +61,6 @@ properties:
     example: "public"
   room_type:
     type: string
-    x-addedInMatrixVersion: "1.4"
     description: |-
       The `type` of room (from [`m.room.create`](/client-server-api/#mroomcreate)), if any.
 required:
diff --git a/data/api/client-server/definitions/room_summary.yaml b/data/api/client-server/definitions/room_summary.yaml
index 239657e3..a8682e51 100644
--- a/data/api/client-server/definitions/room_summary.yaml
+++ b/data/api/client-server/definitions/room_summary.yaml
@@ -23,7 +23,6 @@ allOf:
         description: The `type` of room (from
           [`m.room.create`](/client-server-api/#mroomcreate)),
           if any.
-        x-addedInMatrixVersion: "1.4"
       allowed_room_ids:
         type: array
         items:
diff --git a/data/api/client-server/room_summary.yaml b/data/api/client-server/room_summary.yaml
index 21a58f69..9d23c829 100644
--- a/data/api/client-server/room_summary.yaml
+++ b/data/api/client-server/room_summary.yaml
@@ -71,8 +71,6 @@ paths:
                   - $ref: ../client-server/definitions/room_summary.yaml
                   - type: object
                     properties:
-                      room_type:
-                        x-addedInMatrixVersion: # Overrides room_summary.yaml
                       membership:
                         description: |-
                           The membership state of the user if the user is joined to the room. Absent
diff --git a/data/api/client-server/space_hierarchy.yaml b/data/api/client-server/space_hierarchy.yaml
index 480e4a62..5f6657a2 100644
--- a/data/api/client-server/space_hierarchy.yaml
+++ b/data/api/client-server/space_hierarchy.yaml
@@ -125,6 +125,8 @@ paths:
                                         description: The `origin_server_ts` for the event.
                                     required:
                                       - origin_server_ts
+                            room_type:
+                              x-addedInMatrixVersion: "1.4" # Extends room_summary.yaml
                             allowed_room_ids:
                               x-addedInMatrixVersion: "1.15" # Extends room_summary.yaml
                             encryption:
diff --git a/data/api/server-server/space_hierarchy.yaml b/data/api/server-server/space_hierarchy.yaml
index 99c25ffa..adc2c3e5 100644
--- a/data/api/server-server/space_hierarchy.yaml
+++ b/data/api/server-server/space_hierarchy.yaml
@@ -84,6 +84,8 @@ paths:
                                       description: The `origin_server_ts` for the event.
                                   required:
                                     - origin_server_ts
+                          room_type:
+                            x-addedInMatrixVersion: "1.4" # Extends room_summary.yaml
                           encryption:
                             x-addedInMatrixVersion: "1.15" # Extends room_summary.yaml
                           room_version:
@@ -101,6 +103,8 @@ paths:
                         - type: object
                           title: SpaceHierarchyChildRoomsChunk
                           properties:
+                            room_type:
+                              x-addedInMatrixVersion: "1.4" # Extends room_summary.yaml
                             encryption:
                               x-addedInMatrixVersion: "1.15" # Extends room_summary.yaml
                             room_version: