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When a second child comes along, parents usually end up compromising their last spare guest bedroom or office space to make way. But for one soon-to-be family of four living in a two-story, two-bedroom home in North London, that wasn’t an option—they were already at max capacity. Priced out of most three-bedroom properties, they only had one choice: add on to their current home. The problem was, unlike all their neighbors, they weren’t able to secure planning permissions for a single-story extension. “They couldn’t go higher than the existing roof, which had a much lower profile than the other houses on the street,” says George Bradley, who runs the architecture firm Bradley Van Der Straeten with codirector Ewald Van Der Straeten.

Carving out a new bedroom for the couple’s son (so the baby could take his old space) was still possible; the architects would just have to get creative to make it happen. Their solution? Add only half a floor. “We approached the design as an interlocking jigsaw,” says Bradley. The plan hinged on situating the toddler’s new dwelling directly above the main bedroom. In order to not lose too much ceiling height below, they incorporated a platform bed. “It’s like you’re pulling two strings: If one room on one floor got bigger, the other got a bit smaller,” he explains. Ahead, he shares how they made the extension feel spacious and bright.

The idea to clad the new half-story addition in one material actually came from Bradley’s own plywood-filled home (his clients had seen his space and loved it). They opted for a quality birch that doesn’t have many knots in it and skews more white than it does yellow, providing a blank canvas for colorful toys and accessories. 

One unexpected pro of using the utilitarian material all over is that you don’t notice joints as much. The seamless surface helps conceal lots of clever storage spots in the room, like an extra-tall wardrobe that is designed to look like it extends up through the new skylight. Thin slats even help disguise the radiator underneath the floating shelves. “It would have looked messy if we had used typical plasterboard,” says Bradley. The solid wood beams on the ceiling were a purely aesthetic decision. They create the illusion of added volume. 

In the process of building the half-story, the architects also gained a ton of natural light, plenty of which now shines down into the main hallway through a large plexiglass window by the bedroom door. Taking the feature all the way down to the floor allows adults to quickly glance into the space from the landing without having to walk up the stairs. It also makes games of peekaboo that much more exciting. 

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