diff --git a/src/r_segs.c b/src/r_segs.c
index 354ff35d17ebad51a3cf2f9e7b13275ac6f0e402..dbbbf126b110537da04f97b5c9d7ca375077504c 100644
--- a/src/r_segs.c
+++ b/src/r_segs.c
@@ -2956,7 +2956,7 @@ void R_StoreWallRange(INT32 start, INT32 stop)
 
 	didsolidcol = false;
 
-	if (!segtextured && !numffloors)
+	if (!segtextured && !numffloors && !numbackffloors)
 	{
 		if (markfloor || markceiling)
 			R_MarkSegBounds();