One+ was designed by architect Lars Frank Nielsen of Danish firm ONEN Design, and is a modular housing system that could be used as an office, studio, extra bedroom, guest house or even expanded to be a whole house. The system is based off of a 15 sq meter (161 sq ft) module and can be positioned in various ways in conjunction with other modules for a variety of building designs – just like playing with Legos. Units are prefabricated by Add-A-Room at their factory in Tyresö, then shipped via truck and put into place with a crane. If you’re just getting one unit and there is already a house on your land, you don’t even need a permit for it.
The modules are built with solid Scandinavian materials that require minimal maintenance and a thin outer panel made from Super Wood, which is a Danish invention where Swedish spruce is impregnated into the kernel without heavy metals. Organic solvents are used which provides durability while being environmentally friendly. The units are fully insulated with energy efficient windows and doors from VELFAC, while the pergola provides shade from the sun. A 15 sq m mini house module starts at 250,000 SEK ($35,000 USD) and one with a kitchenette and bathroom is 350,000 SEK. All units come with electricity and plumbing ready to go as well as the veranda and pergola.