This tab contains all of the basic objects that will allow you to create a functional base. One of the most important objects is the ladder. You will have to construct one if you want your colonists to climb higher than two fields. They can jump from one ladder to another ladder if there is one horizontal space between them. You do not need a lot of minerals to build it, and constructing it is also very quick. You can build ladders as temporary scaffolds for building walls or digging ceilings. They have a negative effect on the decor, so do not exaggerate with their quantity, especially in the residential areas. Another very useful structure is the storage compactor. You can store all of the materials that your people dig up from the inside of the asteroid in it. Thanks to that, you can keep the base clean and keep the necessary resources close to the devices that require them (e.g. the coal near to the generator).
Next you have several types of walls and floors. For this purpose you will have to build tiles. You can decide which mineral you will use. Some have a better impact on the environment, others tolerate higher temperatures or are stronger overall. In addition, the movement speed of duplicates is faster on tiles, than it is on fields with raw materials. Over time, you will gain access to specialized tiles. The first of these - the Gas Permeable Tile - as the name implies, allows gases to flow through it (1). However, by itself it does not maintain any amount of gas. This tile does not allow liquids to pass through, so a small amount can block the gas, especially one that is falling (2). Duplicates can still walk on it, though it affects the environment badly. Mesh Tile is the further development of the previous tile (3). It is improved with the possibility of letting liquids through. It is useful in sanitary rooms or other places where you want to have an outlet. Insulated Tiles have the same properties as normal tiles, except that they do not restrict the flow of heat (4). You will use them if you want to fence off a very warm or cold place from the rest of the base, e.g. to protect your garden or enclose a room with hot batteries with electricity.
The last group of objects of similar use are various types of doors. Pneumatic Doors allow the gases and liquids to pass through. They serve only to separate rooms in terms of decor. The Manual Airlock is a very useful object. It will not let through gases or liquids until it is opened. This way you can protect the access to your base from dangerous gases. Appropriate construction of such facilities will significantly contribute to the efficiency of, e.g. oxygen production (it will not disperse where it is not needed). The downside is that they need a moment to open and close. The Mechanized Airlock has the same properties as its manual counterpart, but it opens faster, though it needs electricity to operate. Without electricity they behave like ordinary manual airlocks. By clicking on it, you can choose whether it should run automatically, be constantly closed or constantly open.