diff --git a/docs/changelog.txt b/docs/changelog.txt
index 537686fb9a..0037d2515a 100644
--- a/docs/changelog.txt
+++ b/docs/changelog.txt
@@ -59,8 +59,10 @@ Template for new versions:
 ## New Features
 
 ## Fixes
+- `buildingplan`: Building costs for reinforced walls are now correct.
 
 ## Misc Improvements
+- `buildingplan`: Added support for bolt throwers and siege engine rotation.
 
 ## Documentation
 
diff --git a/library/lua/dfhack/buildings.lua b/library/lua/dfhack/buildings.lua
index 7fff00dcf2..5ea3b1f758 100644
--- a/library/lua/dfhack/buildings.lua
+++ b/library/lua/dfhack/buildings.lua
@@ -130,7 +130,6 @@ local building_inputs = {
             vector_id=df.job_item_vector_id.PIPE_SECTION
         }
     },
-    [df.building_type.Construction] = { { flags2={ building_material=true, non_economic=true } } },
     [df.building_type.Hatch] = {
         {
             item_type=df.item_type.HATCH_COVER,
@@ -353,6 +352,26 @@ local siegeengine_input = {
             quantity=3
         }
     },
+    [df.siegeengine_type.BoltThrower] = {
+        {
+            item_type=df.item_type.BOLT_THROWER_PARTS,
+            vector_id=df.job_item_vector_id.BOLT_THROWER_PARTS,
+        },
+        {
+            item_type=df.item_type.BIN,
+            vector_id=df.job_item_vector_id.BIN,
+        },
+        {
+            name='mechanism',
+            item_type=df.item_type.TRAPPARTS,
+            vector_id=df.job_item_vector_id.TRAPPARTS,
+        },
+        {
+            name='chain',
+            item_type=df.item_type.CHAIN,
+            vector_id=df.job_item_vector_id.CHAIN
+        },
+    },
 }
 --[[ Functions for lookup in tables. ]]
 
@@ -380,6 +399,11 @@ local function get_inputs_by_type(type,subtype,custom)
         return trap_inputs[subtype]
     elseif type == df.building_type.SiegeEngine then
         return siegeengine_input[subtype]
+    elseif type == df.building_type.Construction then
+        if subtype == df.construction_type.ReinforcedWall then
+            return { { flags2={ building_material=true, non_economic=true }, quantity=2 }, { flags3={ metal=true }, item_type=df.item_type.BAR, vector_id=df.job_item_vector_id.BAR } }
+        end
+        return { { flags2={ building_material=true, non_economic=true } } }
     else
         return building_inputs[type]
     end
diff --git a/plugins/lua/buildingplan/planneroverlay.lua b/plugins/lua/buildingplan/planneroverlay.lua
index f92dc95d84..f0fbe17de4 100644
--- a/plugins/lua/buildingplan/planneroverlay.lua
+++ b/plugins/lua/buildingplan/planneroverlay.lua
@@ -119,6 +119,10 @@ local function is_construction()
     return uibs.building_type == df.building_type.Construction
 end
 
+local function is_siege_engine()
+    return uibs.building_type == df.building_type.SiegeEngine
+end
+
 local function tile_is_construction(pos)
     local tt = dfhack.maps.getTileType(pos)
     if not tt then return false end
@@ -235,6 +239,7 @@ local direction_panel_types = utils.invert{
     df.building_type.WaterWheel,
     df.building_type.AxleHorizontal,
     df.building_type.Rollers,
+    df.building_type.SiegeEngine,
 }
 
 local function has_direction_panel()
@@ -1307,10 +1312,16 @@ function PlannerOverlay:place_building(placement_data, chosen_items)
         if is_stairs() then
             subtype = self:get_stairs_subtype(pos, pd)
         end
+        local fields = {}
+        if is_siege_engine() then
+            local facing = df.global.buildreq.direction
+            fields.facing = facing
+            fields.resting_orientation = facing
+        end
         local bld, err = dfhack.buildings.constructBuilding{pos=pos,
             type=uibs.building_type, subtype=subtype, custom=uibs.custom_type,
             width=pd.width, height=pd.height,
-            direction=uibs.direction, filters=filters}
+            direction=uibs.direction, filters=filters, fields=fields}
         if err then
             -- it's ok if some buildings fail to build
             goto continue