Robot-printed bathrooms in 9 hours

Researchers at Nanyang Technological University (NTU) say they have created the world’s first 3D-printed unfurnished bathrooms, in a joint statement released by the university and the National Research Foundation (NRF).

An unfurnished bathroom measuring 1.6m by 1.5m by 2.8m took just nine hours to 3D print, while a larger one, more than twice that size, took 12 hours. The bathrooms can be fitted with all typical toilet fittings and tiles, and comes with concealed drainage and piping.

Since 2014, new non-landed Government residential units have used concrete-casted prefab bathrooms, which are constructed in factories and assembled on site. The 3D-printed bathrooms would take half the time to produce, and at half the cost, researchers say.

“Companies can save inventory and manpower costs as they don’t have to hold as much stock and workers can be redeployed to higher-level tasks,” said Associate Professor Tan Ming Jen, who leads the NTU team.

The technology was developed by scientists from NTU’s Singapore Centre for 3D Printing, in partnership with Sembcorp Design and Construction, and Sembcorp Architects & Engineers.

Over the past three years, the NTU scientists developed four special concrete mixtures—of sand, cement and leftover ash from Sembcorp’s coal power plant—that are suitable for 3D printing. The final mix is fluid enough to flow through the hoses and print nozzle, yet hardens within a few minutes, to allow the next layer to be printed on top. To save material and make the bathroom lighter than a conventional prefab one, the walls are latticed, strengthening the structure.

According to the statement, the larger 3D-printed pre-fabricated bathroom unit had already passed stringent industry tests for strength as well as robustness. It is currently undergoing fire resistance tests in compliance to the requirements under the Building Innovation Panel pre-fabricated bathroom unit acceptance framework.

The research team also aims to obtain the required approvals for trials from the Building and Construction Authority of Singapore (BCA) before commercialising the technology through licensing or a spin-off company, NTU said. ― Construction+ Online