¶ Buildings
Buildings are permanent structures on your planets. They produce resources, defend the planet, host research, store ore and energy, and unlock late‑game megastructures. Almost every empire stat that comes out of a planet — 
production, 
science, food, energy — runs through the planet's mix of buildings.
You manage a planet's buildings from the Planets view.
¶ How buildings work
- A building is built through the planet's production queue. It costs production points — once the queue has accumulated enough, the building is placed. See Production.
- Each building type can exist at most once per planet. There is no "level up" — a Production Hubs is either built or not, you can't have two of them on the same planet.
- No slot limit. You can stack as many different buildings as a planet can afford. Most planets only ever fit a fraction of what's available.
- Some buildings have ongoing credit upkeep (e.g. the Portal Gate costs 100 credits/week). Most are free to operate once built.
- Buildings can be demolished to free the slot for a different one of the same role. There is no refund — the production sunk into the old building is gone.
¶ What buildings do
Buildings stack effects on the planet they sit on. The most common effect categories:
| Category | What it touches | Examples |
|---|---|---|
| Population & food | Food output, supports more population | Hydroponic Farms, Cultured Protein Facility |
| Production | Boosts the planet's weekly production | Production Hubs, Space Elevator Manufacturing Complex |
| Science | Boosts the planet's weekly science | Space Observatory, AI Research Nexus, Quantum Research Grid |
| Credits | Direct credit income (some buildings) or upkeep | Financial Hubs, AI Economic Hub; Portal Gate (upkeep) |
| Energy | Generates / stores energy | Solar Collectors, Nuclear Power Plant, Antimatter Reactor, Zero‑Point Energy Fluctuator |
| Ore | Extraction efficiency, refining, storage | Ore Harvesters, refineries, ore silos |
| Defense | Planetary HP, shields, attack against attacking ships | Planetary Shields, Orbital Laser Array, Antimatter Missile Array |
| Scanning | Increases the planet's own scanning range | Space Observatory |
| Megastructures / special | Unique late‑game projects | Dyson Sphere Construction Facility, Portal Gate, Ringworld‑only buildings |
Effects are cumulative — every building you add piles its contribution onto the planet's totals.
¶ Unlocking buildings
Some buildings are available from turn 1 on every world; the rest are unlocked by researching technology. About 79 of the buildings in the game live behind the tech tree — finishing a tech adds its buildings to your empire‑wide list, and they become buildable on every planet that's allowed to host them.
¶ Where a building can be built
A building can have one of three placement rules:
- Anywhere — most buildings.
- Only on Ringworlds — late‑game ringworld‑exclusive structures like Halo Barrier, Orbital Singularity Cannon, planetoid‑scale mining arrays.
- Not on Ringworlds — many surface‑specific buildings (Terraforming Command Center, surface mining facilities, etc.) — a Ringworld doesn't have a planet surface to put them on.
The Planets view will only show you the buildings that are valid for that world.
¶ Cost & build time
- Production cost ranges from cheap basics (around 4 production for Hydroponic Farms or Resource Silos) to 15,000+ for a Ringworld megastructure like the Planetoid Excavation Array.
- Build time depends entirely on how much production the planet generates per week — a Ringworld can pump a megastructure in a few weeks, while a small new colony will take a long time on anything expensive.
¶ Demolishing
Demolish a building from the Planets view when you want to free up its slot for a different one in the same role (e.g. swap an old reactor for a better one). Demolition is immediate but has no refund — the production cost is sunk. Plan placement on small, cramped planets carefully.
¶ Tips
- Match the planet to the role. Don't try to make every planet do everything — let Ringworlds run megastructures, let ore-rich worlds become refineries, etc.
- Stack the matching bonuses. Planet size and type that match your homeworld both give +50% to production and science. Settling matching worlds is the strongest force multiplier on buildings.
- Don't sleep on defense. A high-value colony with no Planetary Shields is a fat target — a few late-game defense buildings can stalemate an attacker even without ships in orbit.
- Watch upkeep. A few buildings (notably Portal Gates) have credit upkeep that scales with how many you've built. Check the credits view before paving the empire in gates.
¶ Related
- Production — the planet's build queue and what feeds it.
- Research — how new buildings get unlocked.
- Stats reference — what production, science, food, credits, and the other planet stats mean.
- Portals — Portal Gate building specifically.
- Nebulae — the Nebular Harvester ship + the ores that feed late-game buildings.