Central London Penthouse Loft Conversion, Marylebone

The brief

A family had lived in their top-floor mansion block flat for 17 years, a cramped space with a tiny galley kitchen and sloping mansard walls in the master bedroom, unused loft space sitting directly above. The brief was ambitious: turn that unused loft into a full new duplex floor, with proper open-plan living and two more bedrooms, on a site in a conservation area where a traditional glass-roofed extension had already been refused planning permission.

What we did

We designed and built the entire new floor off-site in our North Yorkshire factory, including the two new en-suite bathrooms fully fitted and tiled before they ever left the workshop. The finished modules were transported down to London in sections and craned into place over the roof, with the street closed and a steel cradle used to guide each piece precisely into position. Once craned in, the sections were joined and plumbed on site, with the client’s own choice of German kitchen, sourced from a shop in Glasgow, shipped to our Yorkshire factory to be fitted before installation. The entire build, from demolition to completion, took less than three months, with the most disruptive phases each lasting only a fortnight.

The result

The finished duplex added a vast, dual-aspect living space on the new top floor, two further en-suite bedrooms, and an open-plan living, dining and kitchen area, transforming a dark, boxed-in flat into a genuine penthouse. The project was later featured in the Metro’s Property section, “That’s what you call a home delivery.”