Simcity Buildit Expansions become available at level 10. You can then expand the small dotted areas around the map for more space to build on. The large dashes around the edge are your cities boundaries and can’t be expanded.
Expansions can be purchased using special items gotten from Sim speech bubbles. The items that you’ll need to expand sections are the Dozer Exhaust, Dozer Blade, and Dozer Wheel. They can also be purchase for 24 SimCash each piece, though this is a more expensive alternative.
For more info visit our Simcity Buildit Wiki & Guide.
The cost for each section will always be the same and won’t change. To speed up getting the special items needed for expansion try to keep all Sims happy. When their happy those negative speech bubbles will be positive giving the player more chances for special items.
Eventually you’ll stop getting items from bubbles. You’ll need to wait a little bit before the drop again. Checking on your city after a long way will spawn special items from bubbles right away. So make sure to tap them after some downtime. Keep in mind the the items need also take up space in your Storage. So try to use them right away to make room for goods and items for Disaster Challenges.
(Tip: Though you can’t build outside your cities boundaries, pollution will magical disappear outside of it. Putting buildings that pollute on the very edge is the best way to minimize pollution.)
The below chart shows the cost for each area that can be opened up. The ones on the left (6×10) are slightly bigger then the upper (8×6) parts. They should be one of the first to be unlocked. Later the upper section will be the better deal as far as cost to space ratio is concerned. Each square will fit one piece of road. 4 squares will fit homes and other buildings of the same size.