Building a modern home in London: advice from a modern home architect

Design · Modern homes

What a modern home means for a London house, from rear extensions on period terraces to open-plan zones and daylight, with AURA projects and what a modern home architect does at each stage.

Last updated: 3 November 2026 · Reviewed by Graham Sproul RIBA, Design & Operations Director

What makes a modern home?

On a London house, a modern home comes from a set of design decisions about space and light, and many of them come down to how the ground floor is used. The table sets out the usual features, and what each one has to get right.

Feature	What it does	Design point
Rear or side extension	Adds floor area where the house meets the garden	Keeps the original house readable, often lower or set back from it
Open-plan living with zones	Joins the kitchen and living spaces into one room	Separates the zones with level changes, islands, joinery or ceiling height
Steel-framed glazing	Large openings with slim frames	Orientation decides whether it brings in winter sun or summer heat
Rooflights	Daylight deep into the plan, away from the windows	Positioned over the area that would otherwise be darkest
Insulated fabric	Lower heat loss through walls, floors, roofs and glazing	Specified with U-values on the Building Regulations drawings
Fewer, better materials	A calm palette that ages well	Chosen against the brick, render or stone of the existing house

Those features show up across our work on Victorian and Edwardian terraces and on larger houses outside London. What changes from house to house is the order of priority, and that comes from the brief.

What does a modern home architect do?

A modern home architect turns a brief and an existing house into a design that can be priced and built. On an AURA project that starts with a paid consultation at the house, then a measured survey and a desktop study of the site’s planning history and constraints. We then draw up to three concept options, so you can compare different layouts before committing to one.

Once a concept is chosen, the modern house architect’s job shifts to making it work in detail: the planning drawings, then the Building Regulations package with the structural engineer’s input, then the tender drawings and specification the builders price from. If you’re comparing practices, our guide to choosing the right architect covers what to check before you appoint anyone.

Modern rear extensions on London period houses

Many of the modern home London projects we see are terraced or semi-detached houses from the late 19th or early 20th century. The rear is where the change happens, because the street front is usually protected by planning policy and the garden side has the light. On a period house, the modern extensions that work keep the rhythm of the terrace and make it clear which part is new.

On a wider house the extension can run the full width. At a double-fronted Victorian house in Wimbledon, the main feature is a 4 m deep single-storey extension across the full width, in yellow stock brick with a contrasting zinc parapet, large steel-framed windows and doors to the south-facing garden, and three large rooflights. Large-format limestone floor tiles with underfloor heating run through the open-plan ground floor (Wimbledon kitchen extension project).

At Whitestile Road in Brentford, the brief was a clean, modern extension that fitted in with the existing period property, with bi-fold doors and rooflights for light and a new patio designed as part of the connection with the inside (Whitestile project).

How do you zone an open-plan modern home?

The open-plan spaces that work give each activity its own place: the kitchen where the services and the worktops need to be, the dining table near the glazing, a sitting area that can feel separate in the evening, and somewhere for coats and laundry out of sight. Ceiling height, a step in the floor, an island or a run of joinery can mark the zones without walls.

Some rooms still need doors. In the Wimbledon house, the front reception room with its bay windows can be shut off from the rest of the ground floor with large pocket sliding doors, and opened up when the family entertains. A utility room keeps laundry and clutter out of the open space. Those rooms are planned at concept stage, before the structure is fixed.

Lighting is part of the zoning. A pendant over the table and softer light in the sitting area let one room change character after dark; our guide to lighting design covers how a lighting plan is drawn.

Daylight from glazing and rooflights

Daylight is predictable. In London, at about 51.5°N, the sun reaches 61.9° above the horizon at the June solstice and only 15.1° at the December solstice. High summer sun lands close to the glass; low winter sun reaches deep into the room.

Date	Sun height at noon	Sunlight reaches into the room	What it means for the design
June solstice	61.9°	About 1.3 m	Sun stays near the glazing; an overhang or deep reveal limits summer heat
December solstice	15.1°	About 9 m	Low sun reaches the back of a deep plan, and glare needs thought

That is why a south-facing glass wall can overheat in July and still be welcome in December. Rooflights work differently: they bring light from the brightest part of the sky into the middle of a deep plan, where side windows can’t reach. On the self-build family home we designed in Clapham, an electric opening rooflight with a rain sensor over the open-plan kitchen also ventilates the space in summer.

Worked example: how far the sun reaches

Take a south-facing opening with its head 2.4 m above the floor. The distance the sun reaches into the room at noon is the height of the opening divided by the tangent of the sun’s height.

Date	Sun height	Tangent	Sum	Reach
June solstice	61.9°	1.873	2.4 ÷ 1.873	1.28 m, about 1.3 m
December solstice	15.1°	0.270	2.4 ÷ 0.270	8.9 m, about 9 m

A 4 m deep extension gets summer sun only on the first 1.3 m of floor, while the December sun crosses the whole extension and carries on into the original house. A rooflight at the back of the extension, where the two parts meet, lights the area the glazing can’t reach in summer.

Materials for a modern extension

The materials on a modern extension are chosen against the house. On our projects they have ranged from brick matched to the terrace to cladding that contrasts with it, and the choice usually follows from the planning context.

Material	Project	How it is used
Yellow stock brick with a zinc parapet	Wimbledon, double-fronted Victorian	A full-width 4 m extension in brick to match the house, with a contrasting parapet
Vertical blue tiles and dark metal framing	Dagmar Road, Camberwell	Tiles echo the outriggers along the terrace; the metal-framed infill stays subordinate
London stock brick and steel-framed doors	Marius Road, Balham	A side infill and rear extension designed to tidy a mismatched rear façade
Sedum roof with large rooflights	Maple Lodge, Hertfordshire	An extension of over 5 m with a wildflower sedum roof and rooflights over a covered seating area
Arched glazing with a rooflight in each arch	Toulmin Drive, Hertfordshire	Designed with arches of steel-framed style glazing, vaulted ceilings and a rooflight in each arch

At Maple Lodge the clients’ main worry was light: they didn’t want the new extension to block light into the existing house. The brief included full-height glazing and a fully openable corner (Maple Lodge project). At Toulmin Drive, the arches were designed to let daylight into the new kitchen, with vaulted ceilings and a rooflight in each arch (Toulmin Drive project).

Energy in a modern home

A modern home should cost less to heat than the house did before. The Building Regulations drawings set U-values for each new element, and the builder builds to them. At Dagmar Road, the specification set a U-value target of 0.18 W/m²K for new walls and 0.13 W/m²K for the new ground floor and flat roof, with windows at 1.4 W/m²K.

Element	Specified U-value (W/m²K)
New external walls	0.18
New ground floor	0.13
New flat roof	0.13
New windows	1.4

These are design values, specified on the drawings, not measured results. Heat pumps and solar panels for a London house are covered in our guide to sustainable architecture.

Can you build a modern home in a conservation area?

Many London streets are in conservation areas, where the council looks at whether new work preserves or enhances the character of the area. A modern extension can meet that test when it is clearly subordinate to the house and its materials respond to the street. Whether your project needs planning permission at all is covered in our guide to planning permission vs permitted development.

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