No Basement Please

The housing landscape in Prime Central London has been quietly but profoundly reshaped over the past two decades. Historically, this market was defined by elegant three, four and five-storey townhouses; heritage homes with functional layouts and balanced proportions that worked beautifully for families and professionals alike.

From the early 2000s, however, a powerful trend took hold: the great subterranean expansion. Driven by the race to add square footage and therefore value; homeowners and developers began to look downwards. First came basements, then sub-basements, until entire houses were transformed into multi-level underground complexes. Cinema rooms, gyms, wine cellars, spas and pools became commonplace in areas such as Knightsbridge, Chelsea and Belgravia.

For a time, this dig-down revolution felt unstoppable. Basement space, though costly and disruptive to create, was widely assumed to guarantee profit. Homes were marketed on ever-larger floor areas, often priced on blended £/sq.ft figures that treated underground space as equal to daylight-filled principal rooms.

Yet there’s a reality many buyers only appreciate later: subterranean space is not the same as above-ground living. Rationally, basement square footage should be worth less per square foot; just as a basement flat trades at a discount to a first or second-floor apartment. During the height of the trend, this distinction was frequently ignored. Seduced by headline size, inexperienced buyers focused on total square footage rather than quality and usability, only to discover later that a large proportion of what they’d paid for sat below pavement level, with limited light, more stairs, and higher running costs.

The market reaction against mega-basements wasn’t just cultural - it became statutory. As these ‘iceberg’ developments proliferated, concerns over flooding, impact on neighbours, heritage and cumulative disruption prompted some London boroughs to introduce planning policies to curb the excesses of subterranean expansion.

In the Royal Borough of Kensington and Chelsea, basement policy began to evolve in earnest in the early 2010s and was solidified with revisions around 2014 - 2016. A key change reduced the extent to which basements could extend under a property’s garden from up to 85% of that space down to no more than50 %, and limited those basements, in most cases, to a single storey beneath existing levels.

The City of Westminster followed suit in the mid-2010s, removing permitted development rights for many basement schemes, introducing stricter size and depth limits, and requiring detailed construction management and impact studies.

At the same time, buyer preferences have shifted. We’re now seeing healthy-budget purchasers approach us with the same brief: sensibly scaled, well-proportioned homes in prime locations; ideally with limited or no basement space. The challenge is supply. So much stock has been altered by excavation that these buyers struggle to find what they want.

Today’s Prime Central London buyer often prefers external lifestyle experiences - private clubs, boutique gyms and restaurants, over duplicating these underground at home.

Families, in particular, are turning away from homes where daily life involves navigating multiple staircases. Even buyers with generous budgets are questioning whether basement spas and subterranean leisure suites genuinely improve their way of living.

The result is a structural imbalance. Despite strong demand, many buyers are competing for a shrinking pool of homes that offer simplicity, balance and classic proportions. The drive to maximise underground square footage has, ironically, reduced the supply of exactly what the market now values most.

In short, not everyone is in the market for a subterranean palace. Increasingly, buyers are seeking beautifully scaled, thoughtfully designed homes that support real life, where bedrooms and living spaces are easily accessible, daylight abounds, and lifestyle isn’t buried beneath layers of concrete.

If, like many, you are struggling to find a sensibly scaled, well-proportioned home in Prime Central London, we would be delighted to help.

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• Author Jack Osmond
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