diff --git a/d2m/actions/create-space.js b/d2m/actions/create-space.js
index a7390ed1..3bad2a11 100644
--- a/d2m/actions/create-space.js
+++ b/d2m/actions/create-space.js
@@ -3,6 +3,7 @@
 const assert = require("assert").strict
 const {isDeepStrictEqual} = require("util")
 const DiscordTypes = require("discord-api-types/v10")
+const Ty = require("../../types")
 const reg = require("../../matrix/read-registration")
 
 const passthrough = require("../../passthrough")
@@ -181,9 +182,16 @@ async function syncSpaceFully(guildID) {
 	const spaceDiff = ks.diffKState(spaceKState, guildKState)
 	await createRoom.applyKStateDiffToRoom(spaceID, spaceDiff)
 
-	const childRooms = ks.kstateToState(spaceKState).filter(({type, content}) => {
-		return type === "m.space.child" && "via" in content
-	}).map(({state_key}) => state_key)
+	/** @type {string[]} room IDs */
+	let childRooms = []
+	/** @type {string | undefined} */
+	let nextBatch = undefined
+	do {
+		/** @type {Ty.HierarchyPagination<Ty.R.Hierarchy>} */
+		const res = await api.getHierarchy(spaceID, {from: nextBatch})
+		childRooms.push(...res.rooms.map(room => room.room_id))
+		nextBatch = res.next_batch
+	} while (nextBatch)
 
 	for (const roomID of childRooms) {
 		const channelID = select("channel_room", "channel_id", {room_id: roomID}).pluck().get()
diff --git a/matrix/api.js b/matrix/api.js
index baa5d963..82b1c10e 100644
--- a/matrix/api.js
+++ b/matrix/api.js
@@ -121,6 +121,19 @@ function getJoinedMembers(roomID) {
 	return mreq.mreq("GET", `/client/v3/rooms/${roomID}/joined_members`)
 }
 
+/**
+ * @param {string} roomID
+ * @param {{from?: string, limit?: any}} pagination
+ * @returns {Promise<Ty.HierarchyPagination<Ty.R.Hierarchy>>}
+ */
+function getHierarchy(roomID, pagination) {
+	let path = `/client/v1/rooms/${roomID}/hierarchy`
+	if (!pagination.from) delete pagination.from
+	if (!pagination.limit) pagination.limit = 50
+	path += `?${new URLSearchParams(pagination)}`
+	return mreq.mreq("GET", path)
+}
+
 /**
  * @param {string} roomID
  * @param {string} eventID
@@ -239,6 +252,7 @@ module.exports.getEventForTimestamp = getEventForTimestamp
 module.exports.getAllState = getAllState
 module.exports.getStateEvent = getStateEvent
 module.exports.getJoinedMembers = getJoinedMembers
+module.exports.getHierarchy = getHierarchy
 module.exports.getRelations = getRelations
 module.exports.sendState = sendState
 module.exports.sendEvent = sendEvent
diff --git a/types.d.ts b/types.d.ts
index 2788f60b..68430d93 100644
--- a/types.d.ts
+++ b/types.d.ts
@@ -257,6 +257,18 @@ export namespace R {
 	export type EventRedacted = {
 		event_id: string
 	}
+
+	export type Hierarchy = {
+		avatar_url?: string
+		canonical_alias?: string
+		children_state: {}
+		guest_can_join: boolean
+		join_rule?: string
+		name?: string
+		num_joined_members: number
+		room_id: string
+		room_type?: string
+	}
 }
 
 export type Pagination<T> = {
@@ -264,3 +276,8 @@ export type Pagination<T> = {
 	next_batch?: string
 	prev_match?: string
 }
+
+export type HierarchyPagination<T> = {
+	rooms: T[]
+	next_batch?: string
+}