Twenty-Six Construction is a London design-and-build studio dedicated to the difficult, detailed work of adding to fine houses. We keep our team small, our workload manageable, and our attention where it matters — in the drawing, and on the site.
Founded in 2013 by an architect and a chartered builder who kept ending up on the same projects, Twenty-Six exists to close the gap between how a house is drawn and how it is made. Twelve years on, we are a team of sixteen — designers, engineers, project managers and craftspeople — working exclusively on private residential projects across London and the Home Counties.
The studio is deliberately small. We take on a limited number of projects each year so that the founding partners can remain personally involved in every one.
We believe good construction is a quiet discipline. It resists shortcuts, respects the building it is added to, and takes as long as it needs — but no longer.
The rooms we build are meant to last. That means honest materials, resolved detailing, and a level of finish that reveals itself the closer you look. It also means telling you when an idea will not work, and being willing to draw something four times to get it right.
We work with the building we find. Every intervention is drawn to sit calmly within the character of the host house and the street.
Design and construction sit under one roof. The person drawing your project is talking every day to the person building it.
Materials chosen for permanence. Structure engineered with margin. Ten-year structural warranty on every project we deliver.
Our process is transparent by design. You will know what happens next, what it costs, and who is responsible — at every stage.
A visit to your home. An honest conversation about what is possible, what it might cost, and how long it will take. No obligation.
Measured survey, initial concept sketches and a written feasibility report. Fixed fee. Delivered within three weeks.
Concept resolved, materials selected, structural strategy agreed. Planning drawings prepared and submitted where required.
Detailed construction drawings, engineer's calculations, party-wall notices, and a full-line-item build cost — no hidden extras.
One project manager, one point of contact, weekly updates and photographs. Site kept tidy, neighbours kept informed.
A thorough joint inspection. Nothing signed off until you are content. All finishes documented and warrantied.
Keys, warranty pack, appliance manuals and a maintenance schedule. Ten-year structural warranty registered on your behalf.
Follow-up visits at three, six and twelve months. Any second-year settlement addressed at no additional cost.
Our team is based in Fitzrovia and delivers projects throughout Greater London and the Home Counties. Recent work spans the following areas.
Three architects had drawn our loft. Twenty-Six were the first to look at the roof itself and tell us what it wanted to be. That conversation changed the whole project.— Ms C, SW3
We are currently accepting a small number of new commissions for 2026.
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