U.N. experts predict that 70 percent of the world's population will live in cities by 2050. With urban space already at a premium, there's no way residents of these super cities will be living in vast penthouses. In cities like New York, where housing costs are already astronomical, living in small spaces has become an unofficial sport, with both designers and residents finding fun ways to pack a lot of personality into just a few square feet. If you're still skeptical about living in a house that's the size of an average bedroom, here are five amazing tiny house designs that just might change your mind.

My Micro NY

My Micro NY

Photo: NYC Mayor's Office/Flickr

In January, Mayor Michael Bloomberg announced the winner of adAPT NYC,  a city-sponsored competition that challenged developers to design an micro-apartment that would help the Big Apple solve create more efficient one- and two-person dwellings. My Micro NY was chosen as the winner. Each unit in this 55-dwelling building would be less than 370 square feet, while featuring high ceilings and lots of natural light. Thanks to the implementation of multi-purpose furniture, My Micro NY allows the main space of each unit to be seamlessly re-configured from a living space to a sleeping space and back again.

ProtoHaus

ProtoHaus

Photo: ProtoHaus

One cool thing about tiny homes is that they don't have to play by the same rules as traditional dwellings. When your living space is less than 200 square feet, it's pretty easy to make it fairly portable. If you're the wanderlusting type, ProtoHaus ensures that you can always sleep in your own bed, even while exploring uncharted territory. Fabricated primarily from recycled and reclaimed materials, ProtoHaus is a 125-square-foot home built on a trailer bed. Features include separate freshwater, grey water and black water systems for remote removal and disposal of waste, a solar and wind system to produce power, and a lofted bedroom that fits a queen-size mattress.

Unfolding Apartment

unfolding apartment

Photo: Normal Projects

Designed by Normal Projects, you'd never guess that this spacious Upper West Side apartment was only 450 square feet. The secret to this space-saving renovation is a single, oversized custom cabinetry piece that is inserted along one wall. The cabinet is packed with all of the functional components of a larger apartment including a bed, a nightstand, a closet, a home office, a library, kitchen storage, and most of the lighting for the room. Each element can be deployed or folded up into the wall, depending on the situation.

Lofted East Village Studio

East Village loft

Photo: Jordan Parnass Digital Architecture

The presence of high ceilings is one of the reasons old buildings are the perfect foundation for creating tiny apartments. When you can't develop a space horizontally, designers often vertically instead. This amazing remodeled East Village studio combines much-needed storage spaces and the kitchen, bathroom, and sleeping loft into an intricately sculpted wood-paneled central service core. This leaves lots of room for a beautiful living room and home office space near the big windows at the opposite end of the less than 500 square foot space.

Tiny Texas Houses

Tiny Texas house

Photo: Tiny Texas Houses

Building new homes, no matter how tiny, requires energy and resources. In America's early days, homes were built from healthy, toxin-free, locally harvested materials, usually gathered by the hands of the family who would eventually live in it. The folks at Tiny Texas Houses think it's a shame for all of these high-quality building materials to be tossed into the landfill to make way for mass-produced McMansions. Dedicated to demonstrating the concept of "Pure Salvage Building," this company uses 99 percent repurposed materials to create adorable rustic houses with an average of 250 square feet of space. The Blue Gambrel model pictured above features a comfortable sitting room, mini-kitchen, standup shower in the bathroom, and a lofted bedroom that's sure to give you "Little House on the Prairie" dreams.

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Beth Buczynski is a freelance writer from Colorado who likes coworking, swapping, and meeting new friends through Airbnb. She wrote this post for sharing site yerdle.