diff --git a/data/json/mapgen/house/house_garage.json b/data/json/mapgen/house/house_garage.json
index 7aeba9e9b83bf..00077eef06aa9 100644
--- a/data/json/mapgen/house/house_garage.json
+++ b/data/json/mapgen/house/house_garage.json
@@ -88,5 +88,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        " |||||||||||||||||||||| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |..........<.........| ",
+        " |....................| ",
+        " |....................| ",
+        " |g...................| ",
+        " |F...................| ",
+        " |....................| ",
+        " |J...................| ",
+        " |J...................| ",
+        " |JWUZ....z...........| ",
+        " ||||||...............| ",
+        "      |.zz............| ",
+        "      |...............| ",
+        "      ||||||||||||||||| ",
+        "                        ",
+        "                        ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage2.json b/data/json/mapgen/house/house_garage2.json
index 2bb4ac46cd7c2..495df3f005a46 100644
--- a/data/json/mapgen/house/house_garage2.json
+++ b/data/json/mapgen/house/house_garage2.json
@@ -96,5 +96,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage2_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "             |||||||||| ",
+        "             |........| ",
+        "             |........| ",
+        "             |........| ",
+        "             |........| ",
+        "             |........| ",
+        "             |........| ",
+        "             |........| ",
+        "             |........| ",
+        "             |.......Z| ",
+        "             |<...A..J| ",
+        " |||||||||||||.......W| ",
+        " |........FUg.........| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " ||||||...............| ",
+        "      |...............| ",
+        "      |...............| ",
+        "      |...............| ",
+        "      |...............| ",
+        "      ||||||||||||||||| ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage3.json b/data/json/mapgen/house/house_garage3.json
index ca940e87ba1f8..12031ec5b3811 100644
--- a/data/json/mapgen/house/house_garage3.json
+++ b/data/json/mapgen/house/house_garage3.json
@@ -89,5 +89,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage3_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        " |||||||||||||||||||||| ",
+        " |.................zzz| ",
+        " |..................z.| ",
+        " |....................| ",
+        " |....................| ",
+        " |...................F| ",
+        " |....................| ",
+        " |...................g| ",
+        " |....................| ",
+        " |.............<.JZWJU| ",
+        " |||||||||||||||||||||| ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage4.json b/data/json/mapgen/house/house_garage4.json
index 72e5964c7d708..5a23c03c4f58e 100644
--- a/data/json/mapgen/house/house_garage4.json
+++ b/data/json/mapgen/house/house_garage4.json
@@ -85,5 +85,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage4_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        " |||||||||||||||||||||| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |...................g| ",
+        " |...................U| ",
+        " |.............<.....F| ",
+        " |....................| ",
+        " |...............JJZWJ| ",
+        " |||||||||||||||||||||| ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage5.json b/data/json/mapgen/house/house_garage5.json
index d6b045ceb14e2..742069616d484 100644
--- a/data/json/mapgen/house/house_garage5.json
+++ b/data/json/mapgen/house/house_garage5.json
@@ -82,5 +82,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage5_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "         |||||||||||||| ",
+        "         |g.F.........| ",
+        "         |............| ",
+        "         |............| ",
+        "         |W...%%......| ",
+        "         |J..A%<......| ",
+        "         |Z..U%.......| ",
+        "         |J...%%......| ",
+        "         |J...........| ",
+        " |||||||||............| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " |....................| ",
+        " ||...................| ",
+        "  |...................| ",
+        "  |...................| ",
+        "  |...................| ",
+        "  ||||||||||||||||||||| ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage6.json b/data/json/mapgen/house/house_garage6.json
index eb1c688f3ac32..2bf7e891b2083 100644
--- a/data/json/mapgen/house/house_garage6.json
+++ b/data/json/mapgen/house/house_garage6.json
@@ -116,5 +116,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage6_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "                        ",
+        "  ||||||||   |||||||||  ",
+        "  |......|   |.......|  ",
+        "  |......|   |.......|  ",
+        "  |......|   |.......|  ",
+        "  |......|   |.......|  ",
+        "  |......|   |.......|  ",
+        "  |......|   |.......|  ",
+        "  |.....Z|   |F......|  ",
+        "  |.....J|   |.......|  ",
+        "  |.....W|   |g......|  ",
+        "  |..A...|   |.......|  ",
+        "  |......|||||.......|  ",
+        "  |..................|  ",
+        "  |......%.<.%.......|  ",
+        "  |......%%%%%.......|  ",
+        "  |.......zz.z.......|  ",
+        "  |..........z.......|  ",
+        "  |..................|  ",
+        "  |..................|  ",
+        "  ||||||||||||||||||||  ",
+        "                        ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage7.json b/data/json/mapgen/house/house_garage7.json
index ac4e8ec184587..c1a57b8768b3b 100644
--- a/data/json/mapgen/house/house_garage7.json
+++ b/data/json/mapgen/house/house_garage7.json
@@ -95,5 +95,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage7_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "        ||||||||||||||  ",
+        "        |.g...JJJWZ.U|  ",
+        "        |F..........<|  ",
+        "        |............|  ",
+        "        |............|  ",
+        "        |............|  ",
+        "  |||||||............|  ",
+        "  |..................|  ",
+        "  |..................|  ",
+        "  |..................|  ",
+        "  |..................|  ",
+        "  |..........|||||||||  ",
+        "  |..........|          ",
+        "  |..........|          ",
+        "  |..........|          ",
+        "  |..........|          ",
+        "  |..........|          ",
+        "  ||||||||||||          ",
+        "                        ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/mapgen/house/house_garage8.json b/data/json/mapgen/house/house_garage8.json
index d460c190534e6..c69345f824600 100644
--- a/data/json/mapgen/house/house_garage8.json
+++ b/data/json/mapgen/house/house_garage8.json
@@ -104,5 +104,40 @@
       "palettes": [ "roof_palette" ],
       "terrain": { ".": "t_shingle_flat_roof" }
     }
+  },
+  {
+    "type": "mapgen",
+    "method": "json",
+    "om_terrain": "house_garage8_basement",
+    "object": {
+      "fill_ter": "t_thconc_floor",
+      "rows": [
+        "                        ",
+        "                        ",
+        " ||||||||||             ",
+        " |.......J|             ",
+        " |..A....J|             ",
+        " |.......W|             ",
+        " |.......Z|    |||||    ",
+        " |.......J||||||F.g||   ",
+        " |..................|   ",
+        " |z<................|   ",
+        " |z.................|   ",
+        " |.....|......|.....|   ",
+        " |..................|   ",
+        " |zz.z..............|   ",
+        " |z.................|   ",
+        " ||||||||||||||||||||   ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        ",
+        "                        "
+      ],
+      "palettes": [ "basement_empty" ]
+    }
   }
 ]
diff --git a/data/json/overmap/multitile_city_buildings.json b/data/json/overmap/multitile_city_buildings.json
index ec43494ec858e..79192fd599204 100644
--- a/data/json/overmap/multitile_city_buildings.json
+++ b/data/json/overmap/multitile_city_buildings.json
@@ -2900,7 +2900,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage_basement_north" }
     ]
   },
   {
@@ -2910,7 +2910,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage2_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage2_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage2_basement_north" }
     ]
   },
   {
@@ -2920,7 +2920,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage3_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage3_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage3_basement_north" }
     ]
   },
   {
@@ -2930,7 +2930,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage4_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage4_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage4_basement_north" }
     ]
   },
   {
@@ -2940,7 +2940,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage5_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage5_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage5_basement_north" }
     ]
   },
   {
@@ -2950,7 +2950,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage6_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage6_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage6_basement_north" }
     ]
   },
   {
@@ -2960,7 +2960,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage7_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage7_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage7_basement_north" }
     ]
   },
   {
@@ -2970,7 +2970,7 @@
     "overmaps": [
       { "point": [ 0, 0, 0 ], "overmap": "house_garage8_north" },
       { "point": [ 0, 0, 1 ], "overmap": "house_garage8_roof_north" },
-      { "point": [ 0, 0, -1 ], "overmap": "basement" }
+      { "point": [ 0, 0, -1 ], "overmap": "house_garage8_basement_north" }
     ]
   },
   {
diff --git a/data/json/overmap/overmap_terrain/overmap_terrain_residential.json b/data/json/overmap/overmap_terrain/overmap_terrain_residential.json
index 6dec05af3bef7..2f15971ba4b2a 100644
--- a/data/json/overmap/overmap_terrain/overmap_terrain_residential.json
+++ b/data/json/overmap/overmap_terrain/overmap_terrain_residential.json
@@ -1379,6 +1379,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage2",
@@ -1396,6 +1401,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage2_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage3",
@@ -1413,6 +1423,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage3_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage4",
@@ -1430,6 +1445,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage4_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage5",
@@ -1447,6 +1467,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage5_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage6",
@@ -1464,6 +1489,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage6_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage7",
@@ -1481,6 +1511,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage7_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "house_garage8",
@@ -1498,6 +1533,11 @@
     "color": "light_green",
     "see_cost": 2
   },
+  {
+    "type": "overmap_terrain",
+    "id": "house_garage8_basement",
+    "copy-from": "generic_city_house_basement"
+  },
   {
     "type": "overmap_terrain",
     "id": "garden_house_1_floor_1",