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Last year, U.K. newspaper The Telegraph reported that a $1.5 million London home had collapsed “into a pile of rubble” as its owner attempted to construct a vast, two-story basement extension beneath the period property. Fortunately, no one was hurt, but the incident once again throws a spotlight on the continuing trend of wealthy developers creating what are known as “iceberg homes” in the English capital.

With land prices in London spiraling upwards since the 2008 financial crash, property owners in the city have increasingly chosen to dig down to increase the floor area — and the value — of their tightly packed residences. Unfortunately, this has led to a number of acrimonious clashes between those owners and their neighbors, not to mention planning officers trying to get to grips with the limits of ever more gargantuan proposals throughout London’s most prestigious neighborhoods.

As a means of communicating just how cavernous some of these “super basements” have become, section drawings and plans are ideal. Taking a slice through these properties and their subterranean additions perfectly illustrates this real estate phenomenon, provoking questions about the structural limits of such constructions in densely packed urban areas. We’ve surfaced five of the most outrageous — take a look and let us know what you think of these overblown interventions over on Facebook.

Via Evening Standard

Edmund and Carol Lazarus’ Leisure Center

In 2014, proposals were drawn up for one of London’s largest ever basement extensions beneath a Victorian villa in Holland Park. Proposed by ADAM Architecture for clients Edmund and Carol Lazarus, the 16,000-square-foot, three-story addition was designed to accommodate an 82-foot-long swimming pool, an entertainment room, wine cellar, cigar room, massage rooms, gymnasium, dance studio, hot tub, sauna and steam rooms.

Via Property Report

Jon Hunt’s Car Museum

In 2015, the founder of Foxtons estate agents Jon Hunt submitted plans for arguably the most “mega” of all of London’s mega-basements. A five-story-high “ferris wheel” was designed to display his collection of classic cars. The wheel was proposed as the centerpiece of a subterranean museum for all his vintage vehicles, complete with glass floors and viewing galleries. Mr. Hunt’s plans for the 80-foot-deep extension also included a swimming pool and full-size tennis court.

The footprint of Damien Hirst’s home and of the planned underground extension; images by Purcell, via westminster.gov.uk; gif via Hyperallergic

Damien Hirst’s Art Gallery

Last year, British artist Damien Hirst — reportedly the “World’s Richest Living Artist” — had his planning application for a gargantuan addition below his Grade 1–listed property in London’s Regent Park area. Designed by British architecture firm Purcell, the plans incorporate a two-story-tall “art room,” a cargo elevator capable of lifting large-scale artworks weighing up to 11 tons and an 82-foot-long swimming pool.

Via Daily Mail

Robert Beecham’s Banquet Hall

According to the Daily Mail, businessman Robert Beecham — known for making his fortune selling Star Wars merchandise, no less — “punched the air in delight” when his planning application for a 200-foot-long subterranean extension was approved by Camden council in March 2016. It’s no wonder he was excited — the proposals include, among other things, a salt grotto, a Roman-style tepidarium and a banquet hall with capacity for up to 80 diners.

Via Secret London

The Ultimate Super Basement

Although it is hard to pinpoint the exact address and client for this extraordinary proposal, the section drawing above has been used in countless articles on the subject of London’s basement boom. It is unsurprising, given the incredible depth and programmatic variety on show — with a bowling alley, games room and cavernous climbing wall, this extension would surely make this regal abode the ultimate “iceberg home.”

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