Back in 2016, People's Architecture Office (PAO) designed a novel modular home that could be built within a day using just a hex key called the Plugin House. The firm is still developing the design and recently installed two new models of the Plugin House into dilapidated old houses in a Chinese village.

The Shangwei Village Plugin House project came about because the local government is legally required to renovate homes with collapsed roofs, rather than just knock them down. PAO prefabricated two Plugin Houses to fit within a like number of ruined homes then shipped them in parts to the site and assembled them in a day.

The smaller of the two homes has a total floorspace of just 15 sq m (161 sq ft) and was built inside a ruined house that has most of its roof missing. The larger prefab is in a similarly ruined structure but is a little more spacious at 20 sq m (215 sq ft). It boasts a walled-in garden and generous glazing.

Both homes look modern and light-filled inside. They include living rooms, kitchens, and bathrooms on the ground floor, with bedrooms upstairs. Efficient mini-split units maintain a comfortable temperature inside and, according to PAO, the electricity bills of the homes cost a quarter of those of their neighbors.

The cost of the Shangwei Village Plugin Houses came in at 85,000 Yuan (US$12,200) for the smaller model, while the larger model cost 130,000 Yuan ($19,000).

The project does raise some concerns, such as what will happen if one of the remaining walls or roofs collapse – they look rather rickety in the photos. Hopefully PAO has taken steps to protect against this.