Guide

Industry, density and upgrades

Last updated 13 October 2026

Industry builds the city and then gets in its way. Modernising it is how a smoky town becomes a city people want to live in.

Industry's two jobs

Industry zoning does two things for a Blockline city. It makes the construction materials and consumer goods the city runs on, and it employs people and pays tax. Early on, the first job matters most: almost every build draws materials, so a town without industry eventually can't build at all. Later, the second job takes over, and the smoke from early industry becomes the main thing holding land value down.

The levels of industry

Industrial lots modernise through 4 levels. Each step employs more people and pays more tax, and makes fewer materials, more goods and less smoke.

The rates are relative and all scale with the industrial tax rate, so read across a row rather than treating them as absolute amounts. The pattern is what matters: early workshops are a materials factory with a smoke problem, and high-tech lots are a tax base that barely pollutes.

What each level needs

1. Workshops. Opens at once wherever there is power and a street.
2. Factories. Grows on its own as the lot develops.
3. Clean manufacturing. Density medium or more, and spare skilled workers: residents whose homes are near a school, library or university, anywhere in the city.
4. High-tech. Density high, a university in the city, internet reach and local desirability of 3 or more.

The skilled-worker rule is the one players most often miss. Clean manufacturing hires from homes near schools, libraries and universities, and those homes can be anywhere in the city, not next to the factory. If industry is stuck at factories while your density allows more, build education near your housing.

Tip. Keep some early industry going even in a mature city, or buy materials instead. High-tech lots make very little material, and every later build still needs it.

The clean-energy retrofit

After A skyline of our own, you can convert a connected industrial area to clean energy from an industrial lot's inspector. The city pays $300 per lot up front and $0.25 per lot a day. Converted lots give off 25% of their smoke and 50% of their local nuisance, but draw 1.6× the power. Output, jobs and taxes are unchanged, so it is a direct trade of money and generating capacity for cleaner air.

Zoning density

Density sets how tall a zoned lot may grow and how far industry may modernise. A guided city starts at low density. Completing More than houses permits medium density, and A skyline of our own permits high.

Denser zoning costs more per lot: ×1.5 at medium density and ×2.2 at high. It pays back in homes and jobs per tile, but only where the lot can actually reach those levels, so there is little point zoning high density in a poor, smoky area that will never pass the desirability check.

Upgrading in place

Some buildings can be replaced by a bigger version without bulldozing. Build the larger one straight over the smaller and you pay only the difference in price, while the site keeps working through the change.

The two power upgrades need room: a coal or nuclear plant is a four-tile site, so the tiles beside the old plant must be clear. Widening a road to an avenue is the cheapest upgrade in the game and one of the most useful once traffic builds up (see transport).

The town hall grows by itself

The town hall is the one building you never upgrade by hand. It rebuilds itself grander as the population passes each threshold. Each tier adds civic jobs and city pride, and costs more to run.

For how industry affects the land around it, see desirability; for selling its output, see farms and trade.