The beauty of the settlement system is that you can be as hands on or off as you wish. Settlements will survive whether you take an active role or not but if you wish to see them thrive then you will have to pay attention. Coming to their rescue against raids or monsters, establishing supply lines and creating fortifications are all good ways of improving settlement happiness and size. Managing multiple settlements requires cautious planning and an almost obsessive need to check up on them personally.
The building system in Fallout 4 is simple, allowing you to build massive settlements all with a few button presses. Open the Workshop in the settlement and select the item you wish to build - if you have the required materials then you can immediately build it, with no wait time. Simply place it where you desire and it will pop up completed.
The big questions: where should you build things? How will they affect the settlement? Is the item worth building for the materials it requires? These answers depend on what you wish to achieve from the settlement in the first place but there are a few general considerations to take into account before you start building.
Plan, Plan, Plan
This cannot be overstated when you first start out with your building. Each settlement will have different requirements but especially in space-limited areas, planning is essential to maximise the space and create functional settlements that still thrive. Think about what you wish your goals for a particular place to be and then plan accordingly. So for instance, if you want to build a sprawling fortress, consider where turrets, watch towers, fences and defenses in general will be in relation to the general living areas of your settlers.
If you want to establish supply lines you should decide what resources the settlement may need or contribute. Self-sufficiency will require a good amount of space dedicated to farming and water collection. Try to think about how a settlement may look before you so much as place or scrap anything.
Scrapping is Your Friend
Many settlements will start out with a significant amount of things that can be scrapped to garner materials needed to build new structures and objects. Open the Workshop and search around for items that serve no real purpose like trees (for wood), cars (for steel) and cinder blocks (for concrete). Anything you feel doesn’t add to the settlement you wish to create, feel free to scrap to clear space for the things you do want.
Aside from this, you should make a habit of collecting as many materials as you can when exploring the Commonwealth. Don’t forget that you can place any Junk items from your inventory into a Workshop in a settlement and these will count as materials towards building.
It is best to begin with a basic settlement when you first take over an area, especially if you are already managing several places. It is not a good idea to build a metropolis for a handful of people if you are trying to be efficient and get the most out of each of your settlements. You can always add to and grow them later once the population increases. Just remember to plan well and leave enough space for expansion when you need it. Each settlement can only handle so many items and you may find yourself running out of space before you’ve finished your construction if you aren't careful.
Start From the Ground Up
Uneven terrain will need levelling off if you wish to build something with a sleek look so you should make use of shack foundations. Whenever you need to create something with this design, always begin with these floor pieces. Foundations are a must to achieve a uniform look across the settlement.
If in Doubt, Start From Scratch
If you have plenty of materials and space to accommodate pre-fabricated structures, these can be a great way of getting a settlement up and running in double time. However, they are much harder to alter and change how you want them to look so many of you will want to build something from scratch. You can then build something from a simple hut to a mega tower. If you are serious about settlement building, it is always a good idea to build from scratch where you can.
Vertical Thinking is a Must
Where space is at a premium, which it is in many cases, creating huge skyscrapers is a great way of expanding a settlement while using the space efficiently. Tall buildings are also perfect for setting up defenses with which you can see for hundreds of meters around the settlement, spotting invasions with ease. Not only that, taller buildings are easier to contain inside forts for even better protection. A few taller structures will also leave enough room for farming and water collection.
Waste Not, Want Not
There are a few instances of buildings that cannot be altered or scrapped which you have to then work around. What you can do with these is incorporate them into larger structures, adding to them as you want. Try building on or around them when you want to save space or reduce construction costs.