Extension Architecture

1,800. That is the number of planning applications Extension Architecture has successfully secured across 16 years of residential and commercial work in London and Surrey. A single number of that scale tells you more about how a residential practice actually operates than any portfolio photograph can. It reflects accumulated borough relationships, case officer familiarity, and pattern recognition across thousands of design decisions. For homeowners searching among the many architects london offers, distinguishing between practices that will deliver against ambitious briefs and practices that will produce compromised outcomes requires reading the data behind the marketing rather than the marketing itself. The analysis below unpacks the specific numbers that actually predict project outcomes. The Applications Volume Number That Predicts Everything Volume of planning applications processed correlates strongly with borough-specific expertise. A practice submitting hundreds of application...

Most homeowners searching for London architecture start with portfolio photographs. The images look similar across every serious practice website. Award winning kitchen extensions in Islington. Grade II listed refurbishments in Hampstead. New build homes in Barnes. Photography lies flat about the process that produced any of these outcomes. What actually distinguishes one practice from another sits under the finished photograph. The proof of that distinction shows up in a single data point that most practice websites carry but few visitors think to interrogate. The number of planning applications the practice has successfully secured. Across 16 years of operation from Roehampton, Extension Architecture has delivered over 1,800 approvals across residential briefs in London and Surrey, which is the kind of volume that produces genuine borough knowledge rather than borough claims. If you're searching for london architecture firm with real operational depth behind it, that scale of p...

Ask ten London architects which route works better for a residential loft conversion and you'll get two answers back. Half will recommend permitted development wherever the property qualifies. The other half will argue for a full planning application even when PD sits on the table. Both camps have real evidence behind their position. Neither is wrong. The right answer depends on the specific property, the specific brief, and how much design ambition the family carries into the project. The full argument below sits inside every conversation with a competent loft conversion service team at first appointment, and it's worth understanding both sides before appointing anyone. The PD Camp Argument The permitted development route is faster. That's the starting point. A Prior Approval Notification under Class B of the General Permitted Development Order runs 6 to 8 weeks. Full householder planning applications run 10 to 16 weeks. On projects where the family wants to start on ...

Every family sitting in a London terrace with a growing brood eventually looks up at the ceiling and wonders whether the loft could do more. The honest answer is almost always yes, but the design that works depends entirely on what shape roof you're sitting under. Getting the roof type wrong at concept stage means the wrong planning route, the wrong budget forecast, and often the wrong bedroom footprint on completion. Working with a practice offering full loft conversion design and build means the roof survey happens before the design ambition is set, not after. Four main conversion types cover most London stock. Each one suits a specific roof shape, planning context, and family brief. Hip to Gable Conversions for Semi Detached and End Terrace Houses Semi detached homes and end terraces built between 1900 and 1960 usually carry a hip ended roof. The roof slopes inward at the side rather than running vertically to a gable wall. That hip slope eats into the usable loft volume. Squar...

Somewhere in a Victorian terrace on the north side of Clapham Common, a client walks up two flights of stairs, opens a set of French doors, and steps out onto a private roof terrace with morning coffee in hand. It's a small ritual. It didn't exist eighteen months ago. That daily moment is the outcome of a project completed in late 2024 at 92C Clapham Common. What used to be a cramped, unused attic in a period property is now a master bedroom suite with a walk in wardrobe, ensuite bathroom, and an outdoor terrace enclosed by frameless glass balustrades. The full architectural process and planning route on this particular set of Clapham loft conversions shows how a project of this shape gets past Wandsworth conservation officers without compromising the design intent. The Attic That Was Waiting Most Victorian terraces in Clapham North have an underused space at the top. Steep pitched roofs, small dormers, tiny storage rooms with limited headroom. The floor plate is often gen...

Every architect working in South London learns the same lesson around their tenth Victorian project. The houses look generous from the street and live like rabbit warrens inside. Small rooms. Load bearing walls everywhere. Kitchens trapped at the back. A family in Streatham came to us with one of these terraces. They wanted an open plan kitchen, dining and living zone for entertaining. They also wanted the original marble fireplace and the curved front room walls untouched. Project snapshot Location: Streatham, London Borough of Lambeth Existing footprint: 83.55 sqm Proposed footprint: 94.40 sqm Added floor area: 10.85 sqm Project type: Single storey wraparound + interior design If you want the full architectural pack for this scheme, Double storey wraparound extension   document the local council submission, the structural design and the interior layout from start to finish. The Structural Puzzle of a 19th Century Layout Victorian terraces were built with internal wal...