diff --git a/core/src/io/anuke/mindustry/entities/traits/BuilderTrait.java b/core/src/io/anuke/mindustry/entities/traits/BuilderTrait.java
index 71caeec3d4..35205daa42 100644
--- a/core/src/io/anuke/mindustry/entities/traits/BuilderTrait.java
+++ b/core/src/io/anuke/mindustry/entities/traits/BuilderTrait.java
@@ -193,11 +193,16 @@ public interface BuilderTrait extends Entity, TeamTrait{
 
     /** Add another build requests to the queue, if it doesn't exist there yet. */
     default void addBuildRequest(BuildRequest place, boolean tail){
+        BuildRequest replace = null;
         for(BuildRequest request : buildQueue()){
             if(request.x == place.x && request.y == place.y){
-                return;
+                replace = request;
+                break;
             }
         }
+        if(replace != null){
+            buildQueue().remove(replace);
+        }
         Tile tile = world.tile(place.x, place.y);
         if(tile != null && tile.entity instanceof BuildEntity){
             place.progress = tile.<BuildEntity>entity().progress;
diff --git a/core/src/io/anuke/mindustry/input/InputHandler.java b/core/src/io/anuke/mindustry/input/InputHandler.java
index cfdafc57fd..a7b1eda091 100644
--- a/core/src/io/anuke/mindustry/input/InputHandler.java
+++ b/core/src/io/anuke/mindustry/input/InputHandler.java
@@ -708,7 +708,11 @@ public abstract class InputHandler implements InputProcessor, GestureListener{
 
     public boolean validPlace(int x, int y, Block type, int rotation, BuildRequest ignore){
         for(BuildRequest req : player.buildQueue()){
-            if(req != ignore && !req.breaking && req.block.bounds(req.x, req.y, Tmp.r1).overlaps(type.bounds(x, y, Tmp.r2))){
+            if(req != ignore
+                    && !req.breaking
+                    && req.block.bounds(req.x, req.y, Tmp.r1).overlaps(type.bounds(x, y, Tmp.r2))
+                    && !(type.canReplace(req.block) && Tmp.r1.equals(Tmp.r2))
+            ){
                 return false;
             }
         }
@@ -720,6 +724,10 @@ public abstract class InputHandler implements InputProcessor, GestureListener{
     }
 
     public void placeBlock(int x, int y, Block block, int rotation){
+        BuildRequest req = getRequest(x, y);
+        if(req != null){
+            player.buildQueue().remove(req);
+        }
         player.addBuildRequest(new BuildRequest(x, y, rotation, block));
     }