A wraparound extension fills in the side return and extends the rear of the property simultaneously, creating an L-shaped addition that wraps around the corner of the original structure. It's the combination of the two most common London extension types - rear extension and side return infill - executed as a single build.

The wraparound is the right choice when both the rear and side return have useful depth and width to offer — and when the homeowner wants to address the ground floor comprehensively rather than piecemeal. On a standard Victorian terrace in Chiswick or Hammersmith, a well-executed wraparound can increase the ground floor footprint by 30 to 50 percent.

Wraparound extensions are more complex from a planning perspective than standalone rear or side return extensions. The total volume added is greater, and the L-shaped footprint affects both the rear and side elevations - which means that in conservation areas, the external design receives greater scrutiny. Many wraparound extensions require prior approval or full planning permission depending on their depth and the specific permitted development conditions that apply to the property.

Wraparound extensions in London typically range from £60,000 to £100,000 depending on the combined depth and width of the rear and side return additions, the glazing specification, and the extent of internal reconfiguration. They are the most substantial single-storey extension investment — but also the one that delivers the greatest transformation. On properties in Chelsea SW3, Chiswick W4 and Fulham SW6, the value uplift from a well-executed wraparound consistently justifies the investment.