diff --git a/code/game/objects/structures/roof.dm b/code/game/objects/structures/roof.dm
new file mode 100644
index 000000000000..40f54ca8844e
--- /dev/null
+++ b/code/game/objects/structures/roof.dm
@@ -0,0 +1,151 @@
+/obj/structure/roof
+	name = "roof"
+	desc = "A roof"
+	icon = 'icons/turf/almayer.dmi'
+	icon_state = "plating_catwalk"
+	density = FALSE
+	layer = ABOVE_XENO_LAYER
+	health = 6000
+	var/image/under_image
+	var/image/normal_image
+	var/datum/roof_master_node/linked_master
+	var/lazy_nodes = TRUE
+
+
+/obj/structure/roof/Initialize()
+	. = ..()
+	under_image = image(icon, src, icon_state, layer = layer)
+	under_image.alpha = 127
+
+	normal_image = image(icon, src, icon_state, layer = layer)
+
+	icon_state = null
+
+	RegisterSignal(SSdcs, COMSIG_GLOB_MOB_LOGGED_IN, PROC_REF(add_default_image))
+
+	for(var/icon in GLOB.player_list)
+		add_default_image(SSdcs, icon)
+	if(lazy_nodes)
+		var/obj/effect/roof_node/neighbor = locate() in src.loc
+		if(!neighbor)
+			neighbor = new(src.loc)
+		for(var/direction in CARDINAL_ALL_DIRS)
+			var/adjacent_loc = get_step(src, direction)
+			neighbor = locate() in adjacent_loc
+			if(!neighbor)
+				neighbor = new(adjacent_loc)
+	return INITIALIZE_HINT_LATELOAD
+
+/obj/structure/roof/LateInitialize()
+	. = ..()
+	if(!linked_master)
+		for(var/direction in CARDINAL_ALL_DIRS)
+			for(var/obj/structure/roof/roof in get_step(src,direction))
+				if(roof.linked_master)
+					roof.linked_master.connect(loc)
+					return
+		var/datum/roof_master_node/roof_master_node = new(loc)
+		roof_master_node.connect(loc)
+
+/obj/structure/roof/proc/add_default_image(subsystem, mob/mob)
+	SIGNAL_HANDLER
+	mob.client.images += normal_image
+
+/obj/structure/roof/Destroy()
+	linked_master.remove_roof(src)
+	for(var/icon in GLOB.player_list)
+		var/mob/mob = icon
+		mob.client.images -= normal_image
+	return ..()
+
+/obj/structure/roof/proc/link_master(datum/roof_master_node/master)
+	if(linked_master != null)
+		return
+	master.connected_roof += src
+	linked_master = master
+	for(var/direction in CARDINAL_ALL_DIRS)
+		for(var/obj/structure/roof/roof in get_step(src,direction))
+			roof.link_master(master)
+
+/obj/effect/roof_node
+	name = "roof_node"
+	anchored = TRUE
+	mouse_opacity = MOUSE_OPACITY_TRANSPARENT
+	invisibility = 101
+	unacidable = TRUE
+	var/datum/roof_master_node/linked_master = null
+
+/obj/effect/roof_node/Crossed(atom/movable/mover, target_dir)
+	if(!linked_master)
+		return
+	if(isliving(mover))
+		var/mob/living/mob = mover
+		linked_master.add_under_roof(mob)
+
+/obj/effect/roof_node/proc/link_master(datum/roof_master_node/master)
+	if(linked_master != null)
+		return
+	master.connected_nodes += src
+	linked_master = master
+	for(var/direction in CARDINAL_ALL_DIRS)
+		for(var/obj/effect/roof_node/node in get_step(src,direction))
+			node.link_master(master)
+
+
+
+/datum/roof_master_node
+	var/list/connected_nodes = list()
+	var/list/connected_roof = list()
+	var/list/mobs_under = list()
+	var/location
+
+/datum/roof_master_node/proc/add_under_roof(mob/living/living)
+	if(living in mobs_under)
+		return
+	mobs_under += living
+	RegisterSignal(living, COMSIG_PARENT_QDELETING, PROC_REF(remove_under_roof))
+	RegisterSignal(living, COMSIG_MOB_LOGGED_IN, PROC_REF(add_client))
+	RegisterSignal(living, COMSIG_MOVABLE_MOVED, PROC_REF(check_under_roof))
+
+	if(living.client)
+		add_client(living)
+
+/datum/roof_master_node/proc/add_client(mob/living/mob)
+	SIGNAL_HANDLER
+	for(var/obj/structure/roof/roof in connected_roof)
+		mob.client.images -= roof.normal_image
+		mob.client.images += roof.under_image
+
+/datum/roof_master_node/proc/remove_under_roof(mob/living/living)
+	SIGNAL_HANDLER
+	if(living.client)
+		for(var/obj/structure/roof/roof in connected_roof)
+			living.client.images -= roof.under_image
+			roof.add_default_image(SSdcs, living)
+	mobs_under -= living
+	UnregisterSignal(living, list(
+		COMSIG_PARENT_QDELETING,
+		COMSIG_MOB_LOGGED_IN,
+		COMSIG_MOVABLE_MOVED,
+	))
+
+
+
+/datum/roof_master_node/proc/check_under_roof(mob/living/living)
+	SIGNAL_HANDLER
+	for(var/obj/effect/roof_node/roof in connected_nodes)
+		if(living.loc == roof.loc)
+			return
+
+	remove_under_roof(living)
+
+/datum/roof_master_node/proc/connect(location)
+	for(var/obj/effect/roof_node/node in location)
+		node.link_master(src)
+	for(var/obj/structure/roof/roof in location)
+		roof.link_master(src)
+
+/datum/roof_master_node/proc/remove_roof(obj/structure/roof/roof)
+	connected_roof -= roof
+	if(!length(connected_roof))
+		qdel(src)
diff --git a/colonialmarines.dme b/colonialmarines.dme
index 5193cd3571cb..985c41a6ef44 100644
--- a/colonialmarines.dme
+++ b/colonialmarines.dme
@@ -1313,6 +1313,7 @@
 #include "code\game\objects\structures\prop_mech.dm"
 #include "code\game\objects\structures\props.dm"
 #include "code\game\objects\structures\reagent_dispensers.dm"
+#include "code\game\objects\structures\roof.dm"
 #include "code\game\objects\structures\safe.dm"
 #include "code\game\objects\structures\shower.dm"
 #include "code\game\objects\structures\signs.dm"