diff --git a/js/component/floor_plan.js b/js/component/floor_plan.js
index 3559f1e..4eeb76e 100644
--- a/js/component/floor_plan.js
+++ b/js/component/floor_plan.js
@@ -264,6 +264,7 @@ beestat.component.floor_plan.prototype.set_draggable_ = function() {
     // Deselect when clicking on the background.
     if (
       self.parent_.contains(e.target) &&
+      self.drag_start_mouse_ !== undefined &&
       e.clientX === self.drag_start_mouse_.x &&
       e.clientY === self.drag_start_mouse_.y
     ) {
diff --git a/js/component/floor_plan_entity/point.js b/js/component/floor_plan_entity/point.js
index 6d608f3..259ba25 100644
--- a/js/component/floor_plan_entity/point.js
+++ b/js/component/floor_plan_entity/point.js
@@ -121,7 +121,7 @@ beestat.component.floor_plan_entity.point.prototype.set_room = function(room) {
 };
 
 /**
- * Set the x and y positions of this entity.
+ * Set the x and y positions of this entity. Clamps to the edges of the grid.
  *
  * @param {number} x The x position of this entity.
  * @param {number} y The y position of this entity.
@@ -129,12 +129,19 @@ beestat.component.floor_plan_entity.point.prototype.set_room = function(room) {
  * @return {beestat.component.floor_plan_entity.point} This.
  */
 beestat.component.floor_plan_entity.point.prototype.set_xy = function(x, y) {
+  let clamped_x = x + this.room_.get_x();
+  let clamped_y = y + this.room_.get_y();
+
   if (x !== null) {
-    this.point_.x = Math.round(x);
+    clamped_x = Math.min(clamped_x, (this.floor_plan_.get_grid_pixels() / 2));
+    clamped_x = Math.max(clamped_x, -(this.floor_plan_.get_grid_pixels() / 2));
+    this.point_.x = Math.round(clamped_x - this.room_.get_x());
   }
 
   if (y !== null) {
-    this.point_.y = Math.round(y);
+    clamped_y = Math.min(clamped_y, (this.floor_plan_.get_grid_pixels() / 2));
+    clamped_y = Math.max(clamped_y, -(this.floor_plan_.get_grid_pixels() / 2));
+    this.point_.y = Math.round(clamped_y - this.room_.get_y());
   }
 
   this.update_rect_();
diff --git a/js/component/floor_plan_entity/room.js b/js/component/floor_plan_entity/room.js
index a4baced..89ead7a 100644
--- a/js/component/floor_plan_entity/room.js
+++ b/js/component/floor_plan_entity/room.js
@@ -354,7 +354,7 @@ beestat.component.floor_plan_entity.room.prototype.set_group = function(group) {
 };
 
 /**
- * Set the x and y positions of this entity.
+ * Set the x and y positions of this entity. Clamps to the edges of the grid.
  *
  * @param {number} x The x position of this entity.
  * @param {number} y The y position of this entity.
@@ -362,10 +362,32 @@ beestat.component.floor_plan_entity.room.prototype.set_group = function(group) {
  * @return {beestat.component.floor_plan_entity} This.
  */
 beestat.component.floor_plan_entity.room.prototype.set_xy = function(x, y) {
-  this.room_.x = Math.round(x);
-  this.room_.y = Math.round(y);
+  let clamped_x = x;
+  let clamped_y = y;
 
-  return beestat.component.floor_plan_entity.prototype.set_xy.apply(this, arguments);
+  let min_x = 0;
+  let max_x = 0;
+  let min_y = 0;
+  let max_y = 0;
+  this.room_.points.forEach(function(point) {
+    max_x = Math.max(max_x, point.x);
+    max_y = Math.max(max_y, point.y);
+  });
+  clamped_x = Math.min(x, (this.floor_plan_.get_grid_pixels() / 2) - max_x);
+  clamped_y = Math.min(y, (this.floor_plan_.get_grid_pixels() / 2) - max_y);
+  clamped_x = Math.max(clamped_x, -(this.floor_plan_.get_grid_pixels() / 2) + min_x);
+  clamped_y = Math.max(clamped_y, -(this.floor_plan_.get_grid_pixels() / 2) + min_y);
+
+  this.room_.x = Math.round(clamped_x);
+  this.room_.y = Math.round(clamped_y);
+
+  return beestat.component.floor_plan_entity.prototype.set_xy.apply(
+    this,
+    [
+      clamped_x,
+      clamped_y
+    ]
+  );
 };
 
 /**
diff --git a/js/component/floor_plan_entity/wall.js b/js/component/floor_plan_entity/wall.js
index 6dbbe94..bef694c 100644
--- a/js/component/floor_plan_entity/wall.js
+++ b/js/component/floor_plan_entity/wall.js
@@ -299,7 +299,7 @@ beestat.component.floor_plan_entity.wall.prototype.set_room = function(room) {
 
 /**
  * Set the x and y positions of this entity. This just updates the points as
- * the entity itself is not translated.
+ * the entity itself is not translated. Clamps to the edges of the grid.
  *
  * @param {number} x The x position of this entity.
  * @param {number} y The y position of this entity.
@@ -307,14 +307,23 @@ beestat.component.floor_plan_entity.wall.prototype.set_room = function(room) {
  * @return {beestat.component.floor_plan_entity.wall} This.
  */
 beestat.component.floor_plan_entity.wall.prototype.set_xy = function(x, y) {
+  let clamped_x = x + this.room_.get_x();
+  let clamped_y = y + this.room_.get_y();
+
   if (x !== null) {
-    this.point_1_.x = Math.round(x);
-    this.point_2_.x = Math.round(x);
+    clamped_x = Math.min(clamped_x, (this.floor_plan_.get_grid_pixels() / 2));
+    clamped_x = Math.max(clamped_x, -(this.floor_plan_.get_grid_pixels() / 2));
+
+    this.point_1_.x = Math.round(clamped_x - this.room_.get_x());
+    this.point_2_.x = Math.round(clamped_x - this.room_.get_x());
   }
 
   if (y !== null) {
-    this.point_1_.y = Math.round(y);
-    this.point_2_.y = Math.round(y);
+    clamped_y = Math.min(clamped_y, (this.floor_plan_.get_grid_pixels() / 2));
+    clamped_y = Math.max(clamped_y, -(this.floor_plan_.get_grid_pixels() / 2));
+
+    this.point_1_.y = Math.round(clamped_y - this.room_.get_y());
+    this.point_2_.y = Math.round(clamped_y - this.room_.get_y());
   }
 
   return this;