Cuddles has had different homes in different episodes. It is a tree in some episodes, and in others it is a normal house. His main home is a tree, as it has been seen at least twice in the episodes In a Jam and Hear Today, Gone Tomorrow. His normal-looking house was also seen twice, in the episodes A Hole Lotta Love and Letter Late than Never, although it was destroyed by Pop and Sniffles in the former. He appears to live on a green farm in Don't Yank My Chain.
Giggles, like Cuddles, is shown to live in numerous houses throughout the series. Giggles' house is first seen in Helping Helps, where she lives in a tree and apparently with her mother. This house is later seen in Every Litter Bit Hurts and I've Got You Under My Skin where she appears to live alone. Handy builds her a house in Home Is Where the Hurt Is, though due to several implications, it turns into a giant death trap shaped like an origami crane. The interior of her house is seen in Blind Date. Giggles also has a house in the suburbs in Doggone It where she hangs her laundry out back and a house along Lumpy's mail route in Letter Late than Never. In Dunce Upon a Time, she shared residence with Nutty in a small wooden house with no food, and a bed with a candle on the night stand. In I've Got You Under My Skin, she has a whole variety of toys in her home.
The outside was first seen in either All Flocked Up, where Toothy lives in a normal house, or in Autopsy Turvy (Debatable, because it may be Cuddles' house; if so, the inside of Toothy's house isn't shown until Spare Tire), where he lives in a tree and has a large wardrobe inside it. In Breaking Wind, he lives in a tree.
Lumpy usually lives in a trashy trailer, as evidenced in Nuttin' but the Tooth, You're Bakin' Me Crazy, Stealing the Spotlight, Blind Date, Hear Today, Gone Tomorrow, By The Seat Of Your Pants, and In Over Your Hedge. But he has lived in other places too. When he was a giant in Dunce Upon a Time he lived in a castle in the sky. In Junk in the Trunk he lived in a normal house with a swinging wall and a large set of tubes for his pet elephant. In Aw, Shucks! he had a house out on a farm and destroyed it trying to kill a crow, in Peas in a Pod he had a cottage. In All In Vein, he as a vampire has his own castle where he lures unsuspecting victims by means of deliveries.
Petunia's original house (which resembled a tree) was first seen in Hello Dolly when she brings The Cursed Idol home with her, resulting in her bedsprings impaling her chest and stomach. In Wishy Washy, we get a glimpse of how clean Petunia's house is and how upset she gets when something isn't perfect. Her home makes a reappearance in I Nub You. Petunia also had a small tree house Handy built her in House Warming, but it ended up exploding and setting her aflame. Petunia is also seen in what looks like a cottage in Peas in a Pod. Only the interior of Petunia's house can be seen in Just Be Claus. Her fireplace explodes when Splendid bursts in through the chimney, leaving a large hole in the wall.
First seen in Shard at Work, Handy's home is filled with electrical appliances and hardware which (ironically) need hands to function. The exterior of the house was shown for the first time in No Time Like the Present, which also featured his house with a different interior and pictures of construction tools on the wall. The Mole also lives in the same building, only one floor below.
Nutty lives in a tree that has red and pink stripes on it, resembling a candy cane. He sleeps in candy wrappers on the floor beside his bed despite having a bed. His house has been seen in Concrete Solution, Chew Said a Mouthful, A Sucker for Love Part 1 and Part 2, and False Alarm episode. He also lived with Giggles in a small, wooden house as shown in Dunce Upon a Time. In most episodes, Nutty's house appears to be much smaller on the outside because the shape of the door is different. Other tree houses have a door connected to the ground but Nutty's looks like a hole in a tree. Despite having a small outside appearance, his house is actually much bigger on the inside.
Sniffles lives in a tree made out of metal, first seen in Blast from the Past. Inside he has a lab in which he invents things, though he also has a normal living area elsewhere in the house. He was seen to have a work station in A Hole Lotta Love, but it seems to be a separate building. Sniffles' house has been seen in Blast from the Past, A Sight for Sore Eyes, Tongue in Cheek and I've Got You Under My Skin. However, in internet episodes like Suck It Up and Pet Peeve, he seems to have a different house.
Pop and Cub's House
Pop and Cub's house has been seen on numerous occasions, in episodes like And the Kitchen Sink, Read 'em and Weep, Easy For You to Sleigh, Snip Snip Hooray!, Doggone It, Clause For Concern, A Vicious Cycle, and Out of Sight, Out of Mime their house is a tree. The inside is large and decorated, with separate bedrooms, a kitchen, a bathroom, etc. In Letter Late than Never, Cubtron Z, Chore Loser, and A Handy Nanny, Pop and Cub live in a regular house instead of a tree.
Some believe that her house was seen in Party Animal. Whether it was a rental or permanent home was under debate, until being confirmed by Kenn that the house was indeed written to belong to Flaky. This makes Flaky the only main character who has lived in a normal house (and not a tree) for the entire series. The house has a living room and kitchen, and is located on the top of a hill.
The Mole's House
Like Cuddles and Lumpy, The Mole has had several houses including a tree house and a normal house. In Can't Stop Coffin, he lives partially underground beneath a cemetery (as he's blind, he might not know this, however it may be possible that he lives underground intentionally since he is a mole). However in Out of Sight, Out of Mime and A Sight for Sore Eyes, his home was above the ground. In No Time Like the Present, he lives in a room inside an apartment shared by Handy.
Disco Bear's House
Disco Bear appears to be fairly wealthy, as he has a few luxury homes. One of them is a ski cabin he uses for skiing (which was destroyed in Ski Ya, Wouldn't Wanna Be Ya!). His normal house, first seen in Ipso Fatso and later in Easy Comb, Easy Go, is a 70s style house built off the ground with a set of large steps leading up to his front door. Inside, he has a disco styled bedroom with a large, heart-shaped 70's bed, a disco alarm clock, a self portrait, a painting, a hair-drying chair and a jacuzzi. He also has a bathroom with a floor made of mosaics, each one with a light that activates if it's stomped on, and a weighing machine. He has a more standard-looking tree house in Put Your Back Into It, though the interior still has a 70s look.
Russell's Pirate Ship
First seen in Sea What I Found, Russell's house is a tree house shaped as a pirate ship. In it, there is a hammock in which Russell sleeps and a cupboard where he keeps his clothes, hats, peglegs and hooks when he's not wearing them. In Bottled Up Inside, he is shown to be living in a new house. It looks quite similar to his old house from the TV series, but with major differences. His house is also in YouTube Copyright School.
Lifty and Shifty's Apartment
The outside of their house in Meat Me for Lunch has not been seen, but they were shown to have a small home with a supposedly empty refrigerator. They are shown to live in a hotel apartment in Swelter Skelter. It is possible that their mystery house in the former episode is this very same building.
Seen in Easy For You to Sleigh, Mime to Five, and Chill Kringle, Mime's home is a tent which is like an ordinary house on the inside. Inside, Mime has invisible furniture which Lifty and Shifty once ransacked, much to the horror of Mime.
Seen in Easy For You to Sleigh, Hear Today, Gone Tomorrow, and Autopsy Turvy, and In Over Your Hedge. Flippy's home is shaped like a quonset hut with a hangar where he keeps his military vehicles. He is also shown to be pretty well off as his house is filled with trophies, statues, suits of armor, and a widescreen TV.
Splendid's Acorn Fortress
First seen from the outside in It's a Snap. The inside of his house has been seen in It's a Snap, Better Off Bread, Gems the Breaks and Breaking Wind. A building shaped like an acorn high above the forest, this acts as Splendid's home. Before being called into action, Splendid is usually doing some mundane task like baking bread or knitting.
Lammy's and Mr. Pickels' House
First seen in Royal Flush (only from the inside). It is where Giggles and Petunia are seen at the door and Lammy, Giggles, Petunia, and Flaky are seen at a table playing a card game. When Lammy lets her guests in, there seems to be only a large expanse of hills and trees but nothing else in sight.
Buddhist Monkey's House
First seen in Three Courses of Death. On the outside, it is a red and white oriental house in the center of a small lake. On the inside, it has numerous artifacts including gongs and lanterns. This is the battle site of Buddhist Monkey and Char Sui.
The Ants' Home
The Ants, unsurprisingly, live in an anthill. As is shown in Crazy Ant-ics, their anthill contains a network of underground tunnels akin to its real-life counterparts. However, in Tongue in Cheek, their anthill contains no tunnels and instead has one door for entering and exiting. Their anthill is destroyed by Sniffles' robot in the episode, though they make a new home out of Sniffles' corpse after killing him. In Suck It Up, they do not live in an anthill, but behind the walls of Sniffles' house.
The Dark Shadow Lord's Lair
This is the secret lair of The Dark Shadow Lord, as well as the Generic Tree Ninjas, and possibly Char Sui. It might be an ancient temple or an evil castle. It has a large throne room and a big stained-glass window.
A lot of houses with no known owners have been seen throughout the series. The first time one is seen is in Out of Sight, Out of Mime where several tree houses can be seen at the beginning. In Kringle Karols, a small lone house sits at the top of a hill. Later in Who's to Flame? and From Hero to Eternity, there are several unknown houses around each other in the form of a city. In Letter Late Than Never, a home was shown on a tall cliff, where it caused Lumpy's death when he try to deliver some mail to the houses mailbox. There were also unknown houses in As You Wish, See What Develops, Breaking Wind, A Hole Lotta Love, All In Vein, and False Alarm.