Twenty-Six Construction is a specialist design-and-build practice creating bespoke loft conversions and home extensions for discerning homeowners across London and the surrounding counties.
We are a small, focused team of designers, engineers and craftspeople who specialise in the difficult, detailed work of adding space to fine London homes — without compromising the character of the buildings we touch.
Every project we take on is treated as a piece of architecture in its own right: carefully drawn, structurally resolved, and finished to a standard that lasts. The result is space that feels inevitable — as though it had always been there.
About the practice →From a single Velux to a full mansard reconstruction, every conversion type is drawn from first principles to suit the roof, the street, and the way you live.
Maximise headroom and natural light with stylish, space-enhancing dormers.
Extend your loft seamlessly with a strong and spacious hip-to-gable upgrade.
Create a full-width loft with a sleek finish and exceptional usable space.
Streamlined design that blends with your roof while adding valuable square footage.
Transform corner layouts into multi-functional lofts with smart structural solutions.
Rear, side-return and wrap-around extensions that transform how a home lives at ground level.
We keep architecture, engineering and construction under one roof. That means fewer hand-offs, no design compromises on site, and one accountable team from the first sketch to the final snag.
A small selection of homes we have completed in the last two years — each one a study in proportion, light, and the quiet craft of adding without imposing.
See all projects →They understood the house before they understood the brief. What they built for us feels inevitable — as if the roof had always been that way.— Mr & Mrs H, NW3
Tell us about your home. We will visit, listen, and — if it is a fit — draw something worth building.
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