When you think of construction in most strategy games - even grand strategy games - it's typically a pretty simple affair. You pay a cost, wait for some predetermined time, and then, poof, your new building appears. As should be no surprise by now, Victoria 3 is doing things a bit differently, and construction will be tied in to the rest of your nation's economy in important ways.
Since Victoria 3 covers a time period where most of the world was undergoing rapid industrialisation, it needed a way to simulate the differences in how construction happens at different scales. As a new dev diary explains, your nation will have some level of construction capacity that governs how much construction can happen and how quickly it gets done.
It seems like a pretty elegant system that matches the way Victoria 3 is handling many of its other systems, like military development and industry. You'll start with a government building called a construction sector, which will employ pops and consume resources. The output of the construction sector is just called 'construction,' and it's a measure of the capacity your country has for building stuff.
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