New building projects being developed with the use of 3-D printing technology are pushing the boundaries of concrete construction.

Contractor Andrey Rudenko has officially completed the first 3D printed concrete structure, a backyard castle. Rudenko has an engineering and architecture background, and now he's planning to construct an entire house using the same technology.

"Right now, I am in the process of redesigning the printer based on the lessons learned,” said Rudenko. “My biggest priority is ensuring that the upgraded printer will be ready for the new project. My goal will be to print 24 hours a day until the project is finished," he told

Read More about Rudenko's completed castle project and check out this video from CBS Minnesota.

Architect Adam Kushner is also planning a large 3D printing project. He's planning to construct an entire estate – including a 2,400-square-foot home and a swimming pool –in Gardiner, N.Y.

"To build the massive 3D-printed property, Kushner plans to fly a modified version of Enrico Dini’s oversized D-Shape printer over to New York next January. The printer renders stone-like objects using a combination of sand or other materials with a magnesium-based binder. The house plans are broken up into three parts that will be constructed over time," reports Inhabitat.

Other 3D printed home projects are underway, including the Canal House project in Amsterdam, but this would be the first 3D printed estate, if successful.

Read More about Kushner's plans to build the world's First 3D-Printed Estate