Founded in 2014, Studio Bark is a London architecture studio that specialises in sustainable design. The studio conceived U-Build as a low-impact, open-source building system suitable for the circular economy, where all parts are fully demountable, recyclable and portable.

In 2019, the studio made available the patterns for the U-Build box system to climate change activism group Extinction Rebellion (XR) so that they could make modular plywood roadblock towers, stages and seating for a protest in Trafalgar Square. Studio Bark also adapted the original designs to include a series of holes, allowing activists to ‘lock on’ through the box structure: a peaceful protest tactic that makes it harder for police to arrest individuals. The University of East London, where some of Studio Bark are tutors, undertook a project looking at how the boxes could be configured most efficiently to build different structures. Plywood pieces for 600 boxes were cut for free by Bloqs workshop in North London and supplies were purchased through crowdfunding. Needing only one or two people with a mallet and a drill to assemble the boxes, XR activists were able to configure the boxes quickly into a pre-agreed structure in Trafalgar Square.