Design Tiny Homes "Subversive" Rooftop Cabin Is Shaped Like a Giant Air Duct to Get Around Regulations (Video) By Kimberley Mok Writer McGill University Cornell University Kimberley Mok is a former architect who covered architecture and the arts for Treehugger since 2007. our editorial process Twitter Twitter Kimberley Mok Updated October 11, 2018 ©. PUP Architects Share Twitter Pinterest Email Design Tiny Homes Architecture Interior Design Green Design Urban Design Building on top of city rooftops in response to rising housing costs is an intriguing idea that's been bandied about before. There's some merit to this, as it help to increase urban density, without the need to purchase land. But the process of getting permits for these types of structures can be difficult, costly and may potentially have unfair loopholes. Wanting to challenge these issues and bring awareness to the gentrification of the city's canal waterfront, London firm PUP Architects created this "subversive" rooftop structure, that is shaped like a giant air duct, and clad with recycled Tetra Paks, turned inside out. Take a tour of this rooftop hideout, via Dezeen: © PUP Architects © PUP Architects Built as part of a series of "antepavilions" commissioned by the Architecture Foundation and the property developer Shiva, the rooftop H-VAC aims to draw attention to the recent decisions by the local planning authorities to greenlight large luxury developments along the canal side, while apparently making it difficult for other less-profit-oriented projects to get off the ground. The project also hopes to highlight existing loopholes in local planning regulations that allow for two-storey service structures to be added to roofs. Say the architects: We wanted to provoke a conversation about why, if you can build this type of strange plant equipment on the rooftop, why can we not use it in a more positive way, to inhabit and liberate all these hundreds of thousands of square metres of rooftop space? © PUP Architects © PUP Architects The structure has been built on top of a warehouse that sits beside the canal. It has been framed with wood, and covered with recycled Tetra Paks, the same material used for cartons. Here, the cartons have been turned inside out, folded into squares, and attached to the outside to provide a waterproof skin, though it has been affixed in a way that still lets air and light in. There are benches inside for up to six people to sit, and a big louvered window that allow views of the canal. © PUP Architects © PUP Architects © PUP Architects © PUP Architects © PUP Architects The structure is accessed via a staircase from an artist's studio below. The designers note: Although it was a practical aspect to enter from below, it really added to our concept of the structure being something a little bit subverting what a roof duct is, and this idea of covertness and secrecy. It means that you can use it without ever going on the roof, which is obviously not made to be accessible. © PUP Architects As prime real estate becomes more scarce and costly, developing alternatives and sensible local planning regulations will be key to making major cities more livable and affordable for everyone, not just the well-off. Building on roofs is being explored in some places like Paris and Barcelona, but in reality, it can be costly to stick structures up there, as it's expensive to reinforce the roof and the rest of the building, and to get permits. But it can be done, and ultimately, it's a discussion at least worth having. For more, visit PUP Architects.