diff --git a/src/p_setup.c b/src/p_setup.c
index 2361d1efd..0119e6584 100644
--- a/src/p_setup.c
+++ b/src/p_setup.c
@@ -678,6 +678,7 @@ static void P_LoadRawSectors(UINT8 *data, size_t i)
 		ss->ceilingpic = P_AddLevelFlat(ms->ceilingpic, foundflats);
 
 		ss->lightlevel = SHORT(ms->lightlevel);
+		ss->spawn_lightlevel = SHORT(ms->lightlevel);
 		ss->special = SHORT(ms->special);
 		ss->tag = SHORT(ms->tag);
 		ss->nexttag = ss->firsttag = -1;
diff --git a/src/r_defs.h b/src/r_defs.h
index ea5db3947..65f8ee5c6 100644
--- a/src/r_defs.h
+++ b/src/r_defs.h
@@ -385,6 +385,9 @@ typedef struct sector_s
 	boolean hasslope; // The sector, or one of its visible FOFs, contains a slope
 #endif
 
+	// for fade thinker
+	INT16 spawn_lightlevel;
+
 	// these are saved for netgames, so do not let Lua touch these!
 	INT32 spawn_nexttag, spawn_firsttag; // the actual nexttag/firsttag values may differ if the sector's tag was changed