diff --git a/code/game/objects/items/stacks/sheets/mineral.dm b/code/game/objects/items/stacks/sheets/mineral.dm
index 45bea3fedd8..a66b3e52fdc 100644
--- a/code/game/objects/items/stacks/sheets/mineral.dm
+++ b/code/game/objects/items/stacks/sheets/mineral.dm
@@ -220,6 +220,7 @@ var/global/list/datum/stack_recipe/abductor_recipes = list ( \
origin_tech = "materials=4"
sheettype = "tranquillite"
materials = list(MAT_TRANQUILLITE=MINERAL_MATERIAL_AMOUNT)
+ wall_allowed = FALSE //no tranquilite walls in code
/obj/item/stack/sheet/mineral/tranquillite/New(loc, amount=null)
..()
diff --git a/code/game/objects/items/stacks/sheets/sheets.dm b/code/game/objects/items/stacks/sheets/sheets.dm
index 6c9c61f5a25..b0bbefee9ed 100644
--- a/code/game/objects/items/stacks/sheets/sheets.dm
+++ b/code/game/objects/items/stacks/sheets/sheets.dm
@@ -13,6 +13,7 @@
var/full_window = null //moving the var declaration to here so this can be checked cleaner until someone is willing to make them share a base type properly
usesound = 'sound/items/Deconstruct.ogg'
toolspeed = 1
+ var/wall_allowed = TRUE //determines if sheet can be used in wall construction or not.
// Since the sheetsnatcher was consolidated into weapon/storage/bag we now use
diff --git a/code/game/objects/structures/girders.dm b/code/game/objects/structures/girders.dm
index 0309feb1bcf..b46324a838c 100644
--- a/code/game/objects/structures/girders.dm
+++ b/code/game/objects/structures/girders.dm
@@ -201,6 +201,9 @@
return
var/obj/item/stack/sheet/S = W
+ if(!S.wall_allowed)
+ to_chat(user, "You don't think that is good material for a wall!")
+ return
if(istype(S, /obj/item/stack/sheet/wood))
if(state == GIRDER_DISPLACED)
@@ -313,9 +316,6 @@
if(S.sheettype)
var/M = S.sheettype
- if(M == "tranquillite") //tranquilite walls don't exist in the code (yet)
- to_chat(user, "You don't think that is good material for a wall!")
- return
if(state == GIRDER_DISPLACED)
if(S.get_amount() < 2)
to_chat(user, "You need at least two sheets to create a false wall!")