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Constructions are fixed assets that may be built in states or provinces that are constructed using civilian factories.

State buildings

These buildings are built on a state level. Control of state resources or buildings requires controlling provinces worth at least 50% of the VP of that state, even if that does not include the province where the building icon is located. Airbases will appear, but do not become usable, unless the player also controls the province containing the airbase.

Name Cost Maximum level Effect
Infrastructure.png Infrastructure 3000 10 Determines supply throughput. Increases the speed and recovery rate of land units. Resources output is increased by 10% per level. Increases construction speed of Shared buildingsshared buildings.
Air base.png Air base 1250 10 Bases and repairs air units. Each air base level can host 200 aircraft.
Anti-air (building).png Anti-air 2500 5 Damages attacking air units and reduces damage from bombing. Note that the Anti-Air emplacement only attacks those aircraft attacking the state, not units within the state. This means strategic, tactical, and naval bombers that attack buildings or ports will possibly take damage if there are Anti-Air emplacements, but enemy fighters flying air superiority missions in the state do not take damage.
Radar station.png Radar station 3375 6 (depends on technology) Detects enemy forces, especially incoming aircraft. Radars also help detect enemy ships at sea.

Shared buildings

Like state buildings, shared buildings are built on a state level; however, they share a limited number of slots. This is perhaps the most important category of constructions, since it contains the factories necessary for production.

Name Base Cost Maximum level Effect
Civilian factory.png Civilian factory 10800 20 Produces consumer goods and constructions, or can be used for trade. Base output is 5 (per day).
Military factory.png Military factory 7200 20 Produces equipment. Base output is 5 (per day).
Synthetic refinery.png Synthetic refinery 13000 3 Produces Oil2-6 and Rubber2-6 (Depends on Technology).
Rocket site.png Rocket site 6400 2 Launches rockets.
Nuclear reactor.png Nuclear reactor 30000 1 Produces nuclear bombs.

Infrastructure effects

Construction speed of shared buildings depends on the level of infrastructure in the state. Construction speed is multiplied by

For example ×1.5 at 5 infrastructure. This bonus is applied after bonuses from tech, advisors, and national spirits, making 1 level of infrastructure a more powerful bonus than e.g. a War Industrialist. This encourages players to concentrate industry in central, high-infrastructure areas, although this must be balanced against the increased vulnerability of having all of one's industry in one place.

It is generally not economical to build more infrastructure solely for the purpose of increasing construction speed. Infrastructure is a relatively better deal in states with many empty slots; when planning to build civilian factories, refineries or reactors as they cost more; and at the start with countries with bad economy laws like the USA, as infrastructure construction isn't penalized like factory construction is.

Infrastructure provides diminishing returns to build times. Changing a province's infrastructure from 0 to 1 would require 5 military factories or 3 civilian factories to break even, 1 to 2 is 6 military or 4 civilian, all the way up to 9 to 10 which requires 16 military or 11 civilian.


It is possible to deconstruct shared buildings from the state tab by hovering over the building icon and pressing the X that appears in the lower right corner of the icon.

Slot count

Each state has a category, which then decides the base number of shared slots. Various technologies give percentage bonuses to how many slots a state can have. Various National Foci may give additional bonus slots. The total number of slots is capped at 25.

Building slots.
Category Default number of slots Name in source files Example State
Megalopolis Region 12 megalopolis Greater London Area
Metropolis Region 10 metropolis New England
Dense Urban Region 8 large_city Southern Ontario
Urban Region 6 city Svealand
Sparse Urban Region 5 large_town Nebraska
Developed Rural Region 4 town Sardinia
Rural Region 2 rural Crete
Pastoral Region 1 pastoral Hejaz
Small Island 1 small_island Iwo Jima
Enclave 0 enclave Gibraltar
Tiny Island 0 tiny_island Midway Island
Wasteland 0 wasteland Libyan Desert

Province buildings

These buildings are built on a province level.

Name Cost Maximum level Effect
Land fort.pngLand fort 500 + (500 * Existing Local Fort Level) 10 Reduces the attack and defense of land invaders by 15% per level.
Coastal fort.pngCoastal fort 500 + (500 * Existing Local Coastal Fort Level) 10 Reduces the attack and defense of naval invaders by 15% per level.

Civilian factories

Civilian factories make all the improvements to a territory and are necessary to build any of the constructions listed under the “Constructions” tab. All nations start with a certain number of civilian factories and a percentage will be used for consumer goods, depending on the economy law and national spirits that are currently in place.

Civilian factories that are not used to produce consumer goods can be used for trade or to complete or repair the construction queued in the “Constructions” tab. It's possible to increase the number of civilian factories by building more, but this is limited by the number of Shared buildingsshared buildings slots available in each state.

Consumer goods

Depending on economic laws and national spirits, a number of civilian factories will be occupied by producing consumer goods and are unavailable for construction or trade. This number is computed as a percentage of the total number of factories, rounding upwards. Factories are counted even when they are damaged and can't produce anything.

Consumer Goods.png Universal Country Specific
-10% Flag of Australia Australian national spirit Invest in VictoryInvest in Victory (from focus Squash the Squander Bugs)
+15% Flag of Australia Australian national spirit Great DepressionGreat Depression (from focus National Security Act)
+10% Total MobilizationTotal Mobilization as economy law Flag of Canada Canadian national spirit Great DepressionGreat Depression (from focus Canada Wheat Board)
+15% War EconomyWar Economy as economy law
+20% Partial MobilizationPartial Mobilization as economy law Flag of Australia Australian national spirit Great DepressionGreat Depression (present at start)
+25% Early MobilizationEarly Mobilization as economy law Flag of Canada Canadian national spirit Great DepressionGreat Depression (present at start)
+30% Civilian EconomyCivilian Economy as economy law Flag of United States United States national spirit The Great DepressionThe Great Depression (present at start)
+35% IsolationIsolation as economy law (Flag of United States United States only, from focus Prepare Intervention)
+40% Undisturbed IsolationUndisturbed Isolation as economy law (Flag of United States United States only)

Flag of South Africa South Africa can gain -3% consumer goods at Total MobilizationTotal Mobilization with its spirits, but will not gain additional factories by this.


Suppose the civilian economy law is enabled (requiring 30% of military and civilian factories dedicated to consumer goods) and no other modifiers apply. A country has 50 military factories, 50 civilian ones and 20 Dockyards. It will then have30 (civilian) factories dedicated to consumer goods.


The Factory Output of each civilian factory employed in construction is 5 per day. Construction Speed modifies the output for the building of all constructions.

Construction Speed.png Universal Country Specific
+15% Free TradeFree Trade as trade law
+5% Limited ExportsLimited Exports as trade law
−10% Service by RequirementService by Requirement as conscription law
−30% All Adults ServeAll Adults Serve as conscription law
−40% Scraping the BarrelScraping the Barrel as conscription law

There are also modifiers which only affect a single type of building. These are, primarily, the political advisors (Captain of Industry, Fortification Engineer, Quartermaster General and War Industrialist) but can also be one of many other national spirits activated by national focuses or events.

Efficiency of additional Civilian Factories

The return on investment of building an additional Civilian Factory will depend on the Construction Speed bonus as well the Economy Law currently in place, or expected in the future. The higher the Construction Speed bonus is, the more Output will be done by the newly built Civilian Factory and the faster it will accumulate an Output equal to its cost, 10800. This variable is the time, in days, required to recover the cost of building the factory, or payback time. The Economy Law will dictate what ratio of Civilian Factories are used for Consumer Goods and Output/Trade. The higher this ratio is, the longer the payback time of the newly built Civilian Factory will be. The payback time of a new Civilian Factory is given by the following formula:

The construction speed modifiers range between -70% and +65% and except for the lowest two modifiers, they all have multiple combinations to be achieved. In fact, there are 320 possible combinations of variables affecting Civilian Factory construction speed outside of national spirits and unique laws.

Minimum 0% Maximum
Undisturbed Isolation 8000 2400 2087
Isolation 5539 2216 1773
Civilian Economy 4115 2058 1524
Early Mobilization 2743 1920 1239
Partial Mobilization 2250 1800 1091
War Economy 2218 1695 1027
Total Mobilization 2000 1600 970

Minimal Construction Speed is -70% for Undisturbed Isolation and goes up to -20% with Partial Mobilization. Maximum Speed is 15% for Undisturbed Isolation and 65% with Partial Mobilization. All Values are rounded up to full days.

Additionally, because it's possible to assign up to 15 Civilian Factories (when available) to the construction of a new Civilian Factory, the number of days it will take to build a new one is given by the following formula:

Factory conversion

Civilian Factories can be converted into Military Factories for 4000 and Military Factories can be converted into Civilian Factories for 9000. These base cost is modified by several national spirits and political advisors. To convert a factory simply click on the corresponding state, and hover over the factory that shall be converted. The game will ask for confirmation. After confirmation the conversion now appears in the construction tab, just like any other building project.


Constructions may get damaged by combat or strategic bombing. They repair themselves at a rate of 1% per day. Civilian production may also get allocated to repair constructions at the same base rate as new constructions. This can speed up for the factories by researching Construction I to V, which will boost up the factory repair speed by 10% for every tier.