Roof

thumb|right|210px|The original roof music. The roof is the fifth stage of Adventure Mode and takes place on top of the Player's House. It consists of a five-by-five sloped side in back and a four-by-five straight side in front with a satellite dish on the zombie side and a chimney on the player's side. Both Cabbage-pult and Crazy Dave don't know how the zombies got on the roof in the first place, but at the beginning of roof levels the player can see a ladder at the right that may have helped them.

Effects on the Game
Normal plants (Peashooters, Starfruit, etc.) will not be able to hit zombies if planted on the sloping side (although they can fire over the edge when thumb|right|252px|The in-game variated musicplanted on the first and second sloped column), so the player will need to use lobbed-shot plants for this stage (the player can use Fume-shrooms too, but the need of waking them up and their short range may prevent the player from using them much). They also need Flower Pots to place plants on the roof. Because it takes place during the day, sun falls from the sky during this stage, and mushrooms fall asleep. There are no lawn mowers, so before purchasing roof cleaners from Crazy Dave, the player's last line of defense is, unfortunately, their hindmost plants. This stage also has "ambush zombies", which are actually Zombies (or Conehead Zombies and Buckethead Zombies) that are dropped by Bungee Zombies onto the roof, possibly into the player's defenses, although they can be repulsed by Umbrella Leaves. This is similar to the zombies that surface from the pool and the zombies that come out of graves. Overall, this is the hardest area of the game to overcome.

New plants
The plants added to this level are made especially made to fit the roof. For example, due to the slope of the roof, catapults must be used. These include the Cabbage-pult, Kernel-pult, and Melon-pult, which are all lobbed-shot plants. These plants are essential to roof levels, because of the slope of the roof. Flower Pots are also necessary for planting on the roof. The other plants added in the roof stage are Coffee Beans, Garlics, Umbrella Leaves, and Marigolds.

New zombies

 * Bungee Zombie
 * Ladder Zombie
 * Catapult Zombie
 * Gargantuar
 * Imp

Trivia

 * On the Xbox Live Arcade version, the player can see a large telephone pole in front of the roof. It doesn't appear in Night Roof, however.
 * While it appears that the zombies may have gotten onto the roof with the ladder, the rungs are spaced too far apart for them to use.
 * Some versions of Plants vs. Zombies don't even have a ladder.
 * It is unknown how Vehicle Zombies get up on the roof. However, they may have been dropped by Bungee Zombies. It is still odd how Vehicle Zombies can be lifted by the Bungee Zombies. It may be a group of Bungee Zombies (five to six) for each vehicle. Also, it is odd how Vehicle Zombies can fit in the chimney while still riding their vehicles.
 * When the level is being represented, the words on the screen will say "[The player's name]'s Roof!" with an exclamation point at the end.
 * In the Festive mode on the iOS versions, despite the stocking having a brain with it, the Zombie eats the player's brain instead.
 * The brain on the stocking could be a fake one, although it could be that the zombies are too unintelligent to notice the brain.
 * The music played on the Roof is called "Graze the Roof", a pun on the phrase "raise the roof".
 * Fume-shrooms and Gloom-shrooms are the only non-Lobbed-shot Plants that can shoot up the slope of the roof.
 * During the Roof levels (especially level 5-10) it is unclear how the roof can support all of the heavy zombies, most notably Gargantuars, Zombonis, and Dr. Zomboss's Zombot despite there already being cracks in the roof.
 * In the Xbox 360 trailer, it is said that the roof has Spanish tiles.
 * Despite the fact that the tiles on the roof aren't living, they will still repair over time after a Doom-shroom explosion.
 * Maybe a person inside the house can notice the crater on the roof from the inside and fix it over time.
 * On the Android and iPad versions of the game, there is a hole on the side of the chimney that the zombies walk through, instead of dropping down it.
 * This may be because these versions have wider screens, so the player would be able to see the zombie disappearing and reappearing in the chimney.
 * Strangely, some zombies still have their body visible as they eat the Player's brains. This would imply that the homeowner is sitting in the chimney, watching the battle.
 * It is unknown why Cactus can't grow to reach over the roof's slant, like what it does to attack a Balloon Zombie. This may be because it is used to only shoot Balloon Zombies when stretching up.
 * On the iPad Version, the clouds in the background are shaped like brains.