diff --git a/engine/client/cl_main.c b/engine/client/cl_main.c
index e8c6fb84..52cc8619 100644
--- a/engine/client/cl_main.c
+++ b/engine/client/cl_main.c
@@ -3139,6 +3139,9 @@ static qboolean CL_ShouldRescanFilesystem( void )
 		}
 	}
 
+	if( FBitSet( fs_mount_lv.flags|fs_mount_hd.flags|fs_mount_addon.flags|fs_mount_l10n.flags|ui_language.flags, FCVAR_CHANGED ))
+		retval = true;
+
 	return retval;
 }
 
diff --git a/engine/common/common.h b/engine/common/common.h
index 754bb79c..84ef04e7 100644
--- a/engine/common/common.h
+++ b/engine/common/common.h
@@ -167,6 +167,11 @@ extern convar_t	cl_filterstuffcmd;
 extern convar_t	rcon_password;
 extern convar_t	hpk_custom_file;
 extern convar_t	con_gamemaps;
+extern convar_t fs_mount_lv;
+extern convar_t fs_mount_hd;
+extern convar_t fs_mount_addon;
+extern convar_t fs_mount_l10n;
+extern convar_t ui_language; // historically used for UI, but now controls mounted localization directory
 
 #define Mod_AllowMaterials() ( host_allow_materials.value != 0.0f && !FBitSet( host.features, ENGINE_DISABLE_HDTEXTURES ))
 
@@ -411,6 +416,7 @@ byte *FS_LoadFile( const char *path, fs_offset_t *filesizeptr, qboolean gamediro
 byte *FS_LoadDirectFile( const char *path, fs_offset_t *filesizeptr )
 	MALLOC_LIKE( _Mem_Free, 1 ) WARN_UNUSED_RESULT;
 void FS_Rescan_f( void );
+void FS_CheckConfig( void );
 
 //
 // cmd.c
diff --git a/engine/common/filesystem_engine.c b/engine/common/filesystem_engine.c
index 128f1ab9..f10744c2 100644
--- a/engine/common/filesystem_engine.c
+++ b/engine/common/filesystem_engine.c
@@ -1,4 +1,4 @@
- /*
+/*
 filesystem.c - game filesystem based on DP fs
 Copyright (C) 2003-2006 Mathieu Olivier
 Copyright (C) 2000-2007 DarkPlaces contributors
@@ -21,6 +21,12 @@ GNU General Public License for more details.
 #include "library.h"
 #include "platform/platform.h"
 
+CVAR_DEFINE_AUTO( fs_mount_hd, "0", FCVAR_ARCHIVE|FCVAR_PRIVILEGED|FCVAR_LATCH, "mount high definition content folder" );
+CVAR_DEFINE_AUTO( fs_mount_lv, "0", FCVAR_ARCHIVE|FCVAR_PRIVILEGED|FCVAR_LATCH, "mount low violence models content folder" );
+CVAR_DEFINE_AUTO( fs_mount_addon, "0", FCVAR_ARCHIVE|FCVAR_PRIVILEGED|FCVAR_LATCH, "mount addon content folder" );
+CVAR_DEFINE_AUTO( fs_mount_l10n, "0", FCVAR_ARCHIVE|FCVAR_PRIVILEGED|FCVAR_LATCH, "mount localization content folder" );
+CVAR_DEFINE_AUTO( ui_language, "english", FCVAR_ARCHIVE|FCVAR_PRIVILEGED|FCVAR_LATCH, "selected game language" );
+
 fs_api_t g_fsapi;
 fs_globals_t *FI;
 
@@ -71,7 +77,21 @@ void *FS_GetNativeObject( const char *obj )
 
 void FS_Rescan_f( void )
 {
-	FS_Rescan( 0, NULL );
+	uint32_t flags = 0;
+
+	// FIXME: VFS shouldn't care about this, allow engine to mount gamedirs
+	if( fs_mount_lv.value ) SetBits( flags, FS_MOUNT_LV );
+	if( fs_mount_hd.value ) SetBits( flags, FS_MOUNT_HD );
+	if( fs_mount_addon.value ) SetBits( flags, FS_MOUNT_ADDON );
+	if( fs_mount_l10n.value ) SetBits( flags, FS_MOUNT_L10N );
+
+	g_fsapi.Rescan( flags, ui_language.string );
+
+	ClearBits( fs_mount_lv.flags, FCVAR_CHANGED );
+	ClearBits( fs_mount_hd.flags, FCVAR_CHANGED );
+	ClearBits( fs_mount_addon.flags, FCVAR_CHANGED );
+	ClearBits( fs_mount_l10n.flags, FCVAR_CHANGED );
+	ClearBits( ui_language.flags, FCVAR_CHANGED );
 }
 
 static void FS_ClearPaths_f( void )
@@ -236,6 +256,12 @@ static qboolean FS_DetermineReadOnlyRootDirectory( char *out, size_t size )
 	return false;
 }
 
+void FS_CheckConfig( void )
+{
+	if( fs_mount_lv.value || fs_mount_hd.value || fs_mount_addon.value || fs_mount_l10n.value )
+		FS_Rescan_f();
+}
+
 /*
 ================
 FS_Init
@@ -288,6 +314,11 @@ void FS_Init( const char *basedir )
 	Cmd_AddRestrictedCommand( "fs_clearpaths", FS_ClearPaths_f, "clear filesystem search pathes" );
 	Cmd_AddRestrictedCommand( "fs_make_gameinfo", FS_MakeGameInfo_f, "create gameinfo.txt for current running game" );
 
+	Cvar_RegisterVariable( &fs_mount_hd );
+	Cvar_RegisterVariable( &fs_mount_lv );
+	Cvar_RegisterVariable( &fs_mount_addon );
+	Cvar_RegisterVariable( &fs_mount_l10n );
+
 	if( !Sys_GetParmFromCmdLine( "-dll", host.gamedll ))
 		host.gamedll[0] = 0;
 
diff --git a/engine/common/host.c b/engine/common/host.c
index 231ee278..3a3aeb98 100644
--- a/engine/common/host.c
+++ b/engine/common/host.c
@@ -1310,6 +1310,7 @@ int EXPORT Host_Main( int argc, char **argv, const char *progname, int bChangeGa
 	Cmd_RemoveCommand( "setgl" );
 	Cbuf_ExecStuffCmds();	// execute stuffcmds (commandline)
 	SCR_CheckStartupVids();	// must be last
+	FS_CheckConfig();
 
 	if( Sys_GetParmFromCmdLine( "-timedemo", demoname ))
 		Cbuf_AddTextf( "timedemo %s\n", demoname );