MPs and peers have been warned they should leave the Houses of Parliament for six years to avoid an "impending crisis". The parliamentary restoration and renewal committee said on Thursday that a massive overhaul costing around £4 billion was needed to make the estate safe.
It recommended that MPs move to Richmond House next door – where the Department of Health is currently based – while peers shift to the Queen Elizabeth II Conference Centre nearby, as early as 2020. Otherwise there is a growing risk of a "catastrophic event".
The plans would need to be approved by both houses of parliament. No. 10 said the prime minister wants to "hear the views of MPs before deciding on the direction".
So why has such a drastic course of action been recommended – and what's the rush? BuzzFeed News takes a look.
The basements, vertical shafts, and roof spaces are dangerously congested.
Vital electrical and mechanical systems in parliament are housed in basements, vertical shafts known as "risers", and roof spaces that were designed in the Victorian era. Over the years, new systems have been crammed in on top of old ones – "so that these spaces now contain a bewildering mix of various mechanical and electrical services, from Victorian steam pipes to 21st-century data cables".
The report warns: "Most people who visit the basements for even a short tour are instantly filled with concern at the number and mix of various services which are crammed into small, confined spaces. The heat and the smell are intense. Steam systems, gas lines and water pipes are often laid one on top of another, alongside electricity wires, broadcasting cables and other vulnerable equipment."
The pipes that carry steam from the boilers are corroding and could soon cause a massive leak.
Some of the pipes in parliament date from the 1930s and are corroding badly. Minor leaks of steam happen all the time and problems are often patched up quickly. But there's a limit to what staff can "achieve with such an antiquated and dilapidated system".
The report warns that a fracture in a confined space could lead to a "sudden release of steam at very high temperature which would destroy other services (such as electricity or computer cabling and water pipes) and distribute asbestos fibres". That could put the Commons chamber out of action for months.
Flooding is causing "serious damage" to parliament.
Leaks and floods are a regular occurrence, thanks to crumbling roofs, faulty guttering, and problems with water tanks, pipes, and toilets. Heavy rainfall this summer proved that many of the gutters are no longer fit for purpose.
Work is being carried out to repair and replace the cast-iron roofs – but many of the gutters and downpipes are built into the stonework and can't easily be fixed. Without major repairs, flooding will "continue to cause serious damage to the building", the report says.
There's a real risk of fire spreading through the estate.
The ventilation shafts unintentionally provide an "ideal route for a fire to spread quickly". Forty minor fires were recorded between 2008 and 2012 – and a potentially serious fire happened on 10 June this year on the roof of a plant room near a House of Lords courtyard.
"The fire was quickly discovered and extinguished, but if the same incident had occurred at night, at a weekend, or in a less prominent location, it could have had far more serious consequences," the report says.
The main problem is the lack of compartmentation between sections of the building, meaning that fires can travel quickly throughout the estate. New fire detection units are being installed – but a fundamental overhaul is required, according to the report.
The walls and ceilings are crumbling.
The stonework in some of the smaller courtyards is "visibly crumbling and badly stained". Meanwhile small pieces of timber fall from the roof of Westminster Hall "several times each year", according to the committee.
MPs and peers are risking the building literally falling on their heads. Back in 1980, a piece of the decorative House of Lords chamber ceiling crashed on to the floor below.
Parliament is riddled with asbestos.
Asbestos might be safe while undisturbed but it's extremely dangerous when damaged and fibres become airborne. The report found that asbestos is present in almost every one of parliament's 98 risers (the vertical shafts carrying pipes and wiring between floors) – and these areas are at risk of damage from leaking steam and water.
If asbestos fibres contaminate air ducts, "it is easy to see how one of the chambers, committee rooms or other essential offices might have to be closed down immediately and could be out of action for a significant period of time", the committee says.
The lifts are breaking down.
The Palace of Westminster has 28 lifts, the oldest dating from 1893. A pre-feasibility study in 2012 found that the lifts are "becoming increasingly prone to failure" and only nine are wide enough to be accessed by wheelchair users.
But why does all this work need doing right now?
It's the ageing mechanical and electrical (M&E) services – all those systems hidden from view that have been patched up over the years – that make the need for an overhaul so urgent.
"Complete and sudden failure of the M&E services — the kind that would require the palace to be abandoned immediately — is a real possibility," the report says. "This could be a single, catastrophic failure, such as the complete loss of electrical power to one of the chambers, a devastating fire, extensive flooding, or a gas leak requiring a total evacuation.
"We could also see a series of smaller, incremental failures which, over a period of months or years, would seriously impede, or even put a stop to, normal parliamentary work."
Emily Ashton is a senior political correspondent for BuzzFeed News and is based in London.
Contact Emily Ashton at firstname.lastname@example.org.
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