diff --git a/clientsession.go b/clientsession.go
index 53e8e55..ff8a488 100644
--- a/clientsession.go
+++ b/clientsession.go
@@ -36,9 +36,6 @@ import (
 )
 
 var (
-	// Sessions expire 30 seconds after the connection closed.
-	sessionExpireDuration = 30 * time.Second
-
 	// Warn if a session has 32 or more pending messages.
 	warnPendingMessagesCount = 32
 
@@ -68,8 +65,6 @@ type ClientSession struct {
 	backendUrl       string
 	parsedBackendUrl *url.URL
 
-	expires time.Time
-
 	mu sync.Mutex
 
 	client        *Client
@@ -313,21 +308,6 @@ func (s *ClientSession) UserData() *json.RawMessage {
 	return s.userData
 }
 
-func (s *ClientSession) StartExpire() {
-	// The hub mutex must be held when calling this method.
-	s.expires = time.Now().Add(sessionExpireDuration)
-	s.hub.expiredSessions[s] = true
-}
-
-func (s *ClientSession) StopExpire() {
-	// The hub mutex must be held when calling this method.
-	delete(s.hub.expiredSessions, s)
-}
-
-func (s *ClientSession) IsExpired(now time.Time) bool {
-	return now.After(s.expires)
-}
-
 func (s *ClientSession) SetRoom(room *Room) {
 	s.room.Store(room)
 	if room != nil {
diff --git a/hub.go b/hub.go
index 301ac08..53f6ee4 100644
--- a/hub.go
+++ b/hub.go
@@ -78,6 +78,9 @@ var (
 	// Anonymous clients have to join a room after 10 seconds.
 	anonmyousJoinRoomTimeout = 10 * time.Second
 
+	// Sessions expire 30 seconds after the connection closed.
+	sessionExpireDuration = 30 * time.Second
+
 	// Run housekeeping jobs once per second
 	housekeepingInterval = time.Second
 
@@ -148,7 +151,7 @@ type Hub struct {
 
 	allowSubscribeAnyStream bool
 
-	expiredSessions    map[Session]bool
+	expiredSessions    map[Session]time.Time
 	anonymousSessions  map[*ClientSession]time.Time
 	expectHelloClients map[*Client]time.Time
 	dialoutSessions    map[*ClientSession]bool
@@ -336,7 +339,7 @@ func NewHub(config *goconf.ConfigFile, events AsyncEvents, rpcServer *GrpcServer
 
 		allowSubscribeAnyStream: allowSubscribeAnyStream,
 
-		expiredSessions:    make(map[Session]bool),
+		expiredSessions:    make(map[Session]time.Time),
 		anonymousSessions:  make(map[*ClientSession]time.Time),
 		expectHelloClients: make(map[*Client]time.Time),
 		dialoutSessions:    make(map[*ClientSession]bool),
@@ -600,14 +603,14 @@ func (h *Hub) GetDialoutSession(roomId string, backend *Backend) *ClientSession
 }
 
 func (h *Hub) checkExpiredSessions(now time.Time) {
-	for s := range h.expiredSessions {
-		if s.IsExpired(now) {
+	for session, expires := range h.expiredSessions {
+		if now.After(expires) {
 			h.mu.Unlock()
-			log.Printf("Closing expired session %s (private=%s)", s.PublicId(), s.PrivateId())
-			s.Close()
+			log.Printf("Closing expired session %s (private=%s)", session.PublicId(), session.PrivateId())
+			session.Close()
 			h.mu.Lock()
 			// Should already be deleted by the close code, but better be sure.
-			delete(h.expiredSessions, s)
+			delete(h.expiredSessions, session)
 		}
 	}
 }
@@ -848,7 +851,8 @@ func (h *Hub) processUnregister(client *Client) *ClientSession {
 	delete(h.expectHelloClients, client)
 	if session != nil {
 		delete(h.clients, session.Data().Sid)
-		session.StartExpire()
+		now := time.Now()
+		h.expiredSessions[session] = now.Add(sessionExpireDuration)
 	}
 	h.mu.Unlock()
 	if session != nil {
@@ -980,7 +984,7 @@ func (h *Hub) processHello(client *Client, message *ClientMessage) {
 			prev.SendByeResponseWithReason(nil, "session_resumed")
 		}
 
-		clientSession.StopExpire()
+		delete(h.expiredSessions, clientSession)
 		h.clients[data.Sid] = client
 		delete(h.expectHelloClients, client)
 		h.mu.Unlock()
diff --git a/roomsessions_test.go b/roomsessions_test.go
index 3511ba7..5a8ffe0 100644
--- a/roomsessions_test.go
+++ b/roomsessions_test.go
@@ -26,7 +26,6 @@ import (
 	"errors"
 	"net/url"
 	"testing"
-	"time"
 )
 
 type DummySession struct {
@@ -80,10 +79,6 @@ func (s *DummySession) LeaveRoom(notify bool) *Room {
 	return nil
 }
 
-func (s *DummySession) IsExpired(now time.Time) bool {
-	return false
-}
-
 func (s *DummySession) Close() {
 }
 
diff --git a/session.go b/session.go
index de04ca5..79286a3 100644
--- a/session.go
+++ b/session.go
@@ -69,7 +69,6 @@ type Session interface {
 	GetRoom() *Room
 	LeaveRoom(notify bool) *Room
 
-	IsExpired(now time.Time) bool
 	Close()
 
 	HasPermission(permission Permission) bool
diff --git a/virtualsession.go b/virtualsession.go
index f298265..6288396 100644
--- a/virtualsession.go
+++ b/virtualsession.go
@@ -27,7 +27,6 @@ import (
 	"log"
 	"net/url"
 	"sync/atomic"
-	"time"
 )
 
 const (
@@ -160,10 +159,6 @@ func (s *VirtualSession) LeaveRoom(notify bool) *Room {
 	return room
 }
 
-func (s *VirtualSession) IsExpired(now time.Time) bool {
-	return false
-}
-
 func (s *VirtualSession) Close() {
 	s.CloseWithFeedback(nil, nil)
 }