BLACK SAIL

CLIENT Private
SECTOR Private Residential
SERVICES Concept Design, Developed Design, Planning Approval
STATUS Complete
LOCATION Charlton Kings, Cheltenham, Gloucestershire
MAIN CONTRACTOR William Unwin Design + Build
VALUE Undisclosed
PHOTO CREDIT
John Day
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This project presented an engaging challenge: collaborating with our client to further adapt a recently modernised and extended home. The brief called for an intervention that would sit comfortably alongside previous modifications, while also establishing a distinct visual identity rather than merely replicating what came before.
Additional complexities included working with existing floor levels and ensuring any new addition could be supported by the structural deck already in place—avoiding costly and disruptive works deeper into the home.
We explored multiple iterations, forms, and volumes, all aiming to offset the existing building in a way that felt both practical and playful. The final design introduces a new master bedroom, dressing room, and en-suite bathroom, while retaining an existing shower room for the original bedrooms.
The resulting zinc-wrapped, angled form is tonally complementary to the existing structure yet distinctive enough to add intrigue and character. The angular bay window overlooking the garden subtly borrows additional footprint for the new master suite, while minimising the visual bulk of extending the entire façade. A freestanding bath nestles into this nook—offering the perfect spot to gaze at the sky and treetops.
Paired with a projecting oriel window seat on the opposite elevation, the bedroom feels light, airy, and tranquil—a perfect dual-aspect retreat for our client, away from the hubbub of family life. Exposed structural timber and tactile finishes throughout create a warm, inviting atmosphere that completes this small but perfectly formed addition.













