In the overworld, they intially had a small house until they made an expansion. On the bottom floor, it has their kitchen and a very large chest room with an enchantment room. Upstairs, they have their bedroom, and a small netherwart farm with all of their potions. They also have a hallway, displaying the heads of all the bosses they've defeated so far. It includes the heads of the Lich, the Naga, and the Ur-Ghast. They also have a small expansion outside where they house all of their current Chocobos.
In the Twilight Forest, Cupquake and Red has built a tree house. The tree is hollow inside and has vines all the way up the very tall tall tree to their house. They also added Aether clouds on the bottom so they can drop down from the top. The finished tree house was first shown in episode 34, Sky High Saturday.
Aether (Castle In The Sky)
When they first started making their house they didn't have much done, only a small quaint holystone house untill they decided to make a castle in the sky with a rainbow hill going down from it. The house is mainly built from holystone,an item from the Aether. Now it has a bouncy house and bunnies settling in a fence cage, the bunnies are named Puffin, Muffin And Wuffin. Yet due to the Aether being glitchy, the house is gone for now.
Cloud 9 uses mods from the Hexxit mod pack. A full list of mods can be found on the official website.
The texture pack for Cloud 9 is called "Sphax PureBDcraft 64x64." It can be found on the website BDcraft.