Ice Cream House is a whole-house deep retrofit of a Victorian mid-terrace in Hampstead's Mansfield Conservation Area. The brief was straightforward in its ambition and demanding in its execution: transform a poorly performing period house into a genuinely low-energy family home without losing the character that makes it worth living in, and do it in a way that reflects the personality and heritage of the people who will inhabit it.
Client: J. Montiero
Location: Hampstead, London NW3
Local Authority: Camden Council
Plot Type: Urban
Project Type: Residential – Single Family Home
Internal Area (GIA): 237 sqm
Environmental Performance
The project follows EnerPHit principles throughout, the Passivhaus standard for retrofit, achieving a 70% reduction in energy consumption compared to the building's pre-works performance. The measures that produce this result are unglamorous but consequential: super-insulation at walls, floor, and roof level; a continuous airtight layer across the building envelope; high-performance glazing with minimal thermal bridging at all junctions; mechanical ventilation with heat recovery supplying filtered fresh air throughout; and an air source heat pump replacing the gas boiler entirely. The gas supply has been disconnected. Solar PV sits on the rear roof.
The combination of these measures produces a building that maintains a stable internal temperature with very little energy input, that has excellent air quality throughout, and that costs a fraction of a standard Victorian terrace to run. These outcomes are measurable and verified, not modelled assumptions.
Spatial Strategy
The existing house was extended at side and roof level, with a dormer addition creating usable space on the upper floor, and a side extension improving the relationship between the ground floor and the garden. A glazed envelope in two parts brings light deep into the middle reception, which in the original configuration received very little daylight.
The new staircase runs from lower ground to third floor in light oak, with timber balusters and open treads that allow light and views to pass through the structure. It functions as the building's spine, connecting every level and every room in a way that makes the house feel continuous rather than stacked.
Interior and Material Palette
Our clients are Italian and Portuguese by background, and they brought a sensibility about domesticity that shaped every material decision we made. The palette is lively without being restless: polished concrete floors run from the kitchen to the rear terrace, terrazzo appears in the bathrooms and utility spaces, and tadelakt, a traditional Moroccan lime plaster, covers bathroom walls and ceilings in a finish that is both water-resistant and tactile in a way that ceramic tile simply isn't.
The name came from the clients' shared enthusiasm for ice cream, which made its way into the bathroom palette more directly than you might expect: the colours are warm, the finishes sensory, and the effect is a house that feels genuinely inhabited by the people who live in it rather than styled for a photoshoot.
Across the main living spaces the approach is more restrained, allowing the architecture, the light, and the clients' art, guitars, and furniture to be the dominant presence.
The Playroom
The children's playroom deserves a specific mention because it is one of the more considered rooms in the house. It occupies an intermediate level and includes a mezzanine reached by a short flight of steps, with a suspended hammock above. It is unambiguously a room designed to be used by children, which is not something every renovation remembers to do. It cost no more to design well than to design badly, and the children have claimed it entirely.