British Parliament's home, the Palace of Westminster, is showing its age. To address issues including water leaks, poor wiring, and risk of fire, a multi-billion pound refurbishment is required that's likely to shut the place for six years. To allow the government to go about its business as usual in the meantime, Gensler has designed a futuristic water-based modular building.

The concept building, dubbed Project Poseidon, would allow Members of Parliament to meet on the River Thames, just a stone's throw from their current aging workplace, directly adjacent to the existing Member's terrace. It could operate as a standalone building or potentially integrate with areas of the Palace of Westminster during the refurbishment.

Gensler says it would be designed and built in UK shipyards over three years and floated down the Thames in prefabricated sections before being assembled. The building itself would measure 250 x 42 m (820 x 137 ft) and would be supported on a series of steel platforms. A barrier would provide protection from passing water-borne craft.

According to Gensler, the striking glazed design draws inspiration from the famous 14th Century hammer-beam timber roof of Westminster Hall.

If the project goes ahead (and to be clear, there's no suggestion this is particularly likely at this stage), the firm estimates it would cost £160 million (US$204 million) and take three years to build.

Spending so much for temporary digs seems potentially excessive, though Gensler says that Project Poseidon could reduce the total refurbishment costs by up to £1.8 billion ($2.3 billion). We've reached out to the firm for further details on how it arrived at that figure and will update this story if we hear back.

The project comes after last year's crowdfunding project for another ambitious vision that would make more use of the Thames by building a floating, sustainably-powered cycle path on it.

You can hear the thoughts of a few members of the public in the video below.

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