diff --git a/unilabos/resources/itemized_carrier.py b/unilabos/resources/itemized_carrier.py
index c56cc8b4..ddda316f 100644
--- a/unilabos/resources/itemized_carrier.py
+++ b/unilabos/resources/itemized_carrier.py
@@ -88,6 +88,8 @@ class ItemizedCarrier(ResourcePLR):
     )
     self.num_items = len(sites)
     self.num_items_x, self.num_items_y, self.num_items_z = num_items_x, num_items_y, num_items_z
+    self.layout = "z-y" if self.num_items_z > 1 and self.num_items_x == 1 else "x-z" if self.num_items_z > 1 and self.num_items_y == 1 else "x-y"
+
     if isinstance(sites, dict):
       sites = sites or {}
       self.sites: List[Optional[ResourcePLR]] = list(sites.values())
diff --git a/unilabos/resources/warehouse.py b/unilabos/resources/warehouse.py
index 775c55aa..67facde7 100644
--- a/unilabos/resources/warehouse.py
+++ b/unilabos/resources/warehouse.py
@@ -5,10 +5,13 @@ from pylabrobot.resources.carrier import ResourceHolder, create_homogeneous_reso
 from unilabos.resources.itemized_carrier import ItemizedCarrier, ResourcePLR
 
 
+LETTERS = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+
+
 def warehouse_factory(
     name: str,
-    num_items_x: int = 4,
-    num_items_y: int = 1,
+    num_items_x: int = 1,
+    num_items_y: int = 4,
     num_items_z: int = 4,
     dx: float = 137.0,
     dy: float = 96.0,
@@ -33,13 +36,16 @@ def warehouse_factory(
                 locations.append(Coordinate(x, y, z))
     if removed_positions:
         locations = [loc for i, loc in enumerate(locations) if i not in removed_positions]
-    sites = create_homogeneous_resources(
+    _sites = create_homogeneous_resources(
         klass=ResourceHolder,
         locations=locations,
         resource_size_x=127.0,
         resource_size_y=86.0,
         name_prefix=name,
     )
+    len_x, len_y = (num_items_x, num_items_y) if num_items_z == 1 else (num_items_y, num_items_z) if num_items_x == 1 else (num_items_x, num_items_z)
+    keys = [f"{LETTERS[j]}{i + 1}" for i in range(len_x) for j in range(len_y)]
+    sites = {i: site for i, site in zip(keys, _sites.values())}
     
     return WareHouse(
         name=name,