The Electrical Room needs to be directly under the “Above Ground” part of the base and we also need to make sure that it’s 4 blocks high. Best way to do this is to simply look down the shaft and place a Wood Frame Block on the 5th spot down and ensure that there are 4 blocks of space between the Above Ground floor and the Electrical Room floor. This block is the start of the Electrical Room’s floor.
Dig out a 5 by 4 room getting rid of the clay all the way up to the ceiling. You should see the Above Ground foundations exposed. Place Wood Frame blocks on the ground flush with the Wood Frame Block you placed in the first step.
Upgrade the floor blocks and the Ladder support blocks to Cobblestone.
Fill in 3 walls, the ladder wall and left and right side with Wood Frame Blocks and upgrade them to Cobblestone. Start with the corners first. Don’t worry about the back wall, we’ll do this one in the next step.
IMPORTANT: Do not upgrade or touch the Above Ground foundations blocks, even though some of them are still wood. They are meant to be removed later when we’re ready to install electrical components.
Now let’s do the back wall. Fill it in with Wood Frame Blocks all the way up to the ceiling, but leave 2 spots in the center empty for the door. Update to Cobblestone then install a Wooden Door.
Remove one of the Ladders closest to the Shaft and install a Wooden Hatch.
Open the back wall Wooden Door and dig out 3 blocks in, starting from the floor all the way up to the ceiling. Place Wood Frame Blocks on the floor and upgrade to Cobblestone.
On the 3rd furthest spot, place 4 Wood Frame Blocks all the way up to the ceiling and upgrade them to Cobblestone.
Dig up a 3×2 area on each side of this previously place column starting from floor all the way up to the ceiling. Place Wood Frame Blocks for the floor and upgrade to Cobblestone.
Fill in the back walls on each side of the column. Upgrade to Cobblestone.
Fill in the left side and right side walls with Wood Frame Blocks and upgrade to Cobblestone.
Make sure not to touch / upgrade the blocks that belong to the Above Ground foundation even if they are only wood.
Do the same thing again on each side but only with 4 blocks instead of 6. We need to leave a gap of 2 blocks. Upgrade to Cobblestone.
Install Ladders between the two previously placed walls. Those Ladders will give access to electrical components once they are installed.
