Houses are getting smaller and many young people are forced to share with others. Submariners know some practical and psychological tricks for living in cramped spaces, writes Sonia Rothwell.

Submarine Lt Cmdr Charlie Neve sometimes spent 100 continuous days underwater. His wider home - the whole submarine - might be 150m long, 12m wide and 12m high.

HMS Alliance, the Cold War-era vessel at the Royal Navy Submarine Museum, and similar in size to some of Neve's submarines, is even smaller than that at 86m long and just over 5m wide.

In the UK, the Royal Institute of British Architects estimates the floor area of the average new three-bedroom home in the UK as 88 square metres (947 sq ft).

But imagine sharing a tiny space with up to 160 other men and a cornucopia of cables, pipes, valves, engines and other equipment.

Image copyright PA Image caption HMS Alliance - now on display at the Royal Navy Submarine Museum in Gosport

Even though submariners typically only do three or so long tours at sea in a two-year period, the discipline of that environment stays with them. As do some of the effects of living in very compact conditions.

The Why Factor: Why Do Humans Need So Much Space is broadcast at 18:32 GMT on 11 September on BBC World Service Listen on BBC iPlayer Radio

In civilian life, a single bed might measure 90cm x 190cm. The bunks in submarines are around 60cm x 180cm so they're nicknamed "coffins".

"Many people talk about the 'coffin dreams' they used to have in their bunks," says Neve. "I have had my own coffin dreams and my wife tells me I still do."

As well as the snug nature of the "coffins", even in today's vessels some submariners have to "hot-bunk". When someone's six-hour shift finishes and they want to get to sleep, their bunk has usually just been vacated by someone else.

Image copyright Getty Images

That's extreme, but other challenges faced on submarines will be familiar to those in small flats and houses.

If essential cargo can be put to a dual use on a submarine then so much the better. Items such as cans of beer can be stored in missile tubes because they stay cool. Lavatories might be used to store cleaning equipment.

Image copyright Getty Images Image caption Never leave the mess in a mess

Canned food is also relatively easy to accommodate. "You can tie down things you can stand on like cans and store them on the walkways," says Neve. The downside of this however is that headroom is reduced "by the height of a tin of beans".

Submarines are not just living spaces, they're work spaces too. Bunks three-high line the walkways and recreation space fitted in seemingly as an afterthought around the sub's core areas and equipment. Only a thin curtain can separate a dozing seaman from his colleagues working nearby.

In the case of an older and smaller sub like HMS Alliance, the area containing the conning tower and periscopes is the area of a decent-sized garden shed. While practising an attack, the space could contain 20 personnel operating in a high-pressure situation.

Image copyright National Museum of the Royal Navy Image caption The periscope area in HMS Alliance: Relatively spacious

Adjusting to living in a small space shared with others requires a certain mindset. Those who are naturally tidy fare better than their more chaotic peers. "The first thing I would say to people living in cramped conditions is understand the level of organisation, tidiness you need," says Neve.

"Somebody like our normal, typical teenager who leaves everything around, is not immediately deemed to be suited to living in small spaces. But I would hope that they learn that those small spaces only get smaller if you leave everything lying around".

Image copyright ALAMY Image caption Untidy habits would be intolerable in a submarine

Neve says the Royal Navy training process usually weeds out most of the pathologically untidy, who decide their prospective working environment is not suited to their natural level of organisation.

At sea, leaving your stuff all over the place can be hazardous if the sub has to make an emergency dive or surface unexpectedly.

Inevitably though, some untidy people do still manage to go on to work on a submarine. Their bad habits don't last long, Neve says.

If someone continually left their boots out and didn't put them back in their locker, their boots wouldn't be available... when they got up in the morning Lt Cmdr Charlie Neve, HMS Alliance

If simply living among better-organised colleagues doesn't change their behaviour, persistent offenders can face anonymous action to make them clean up their act.

"Tactics vary from a sharp word to something more devious," says Lt Cmdr Neve. "If you leave something lying around you're not going to see it again.

"What we used to do quite regularly if someone continually left their boots out and didn't put them back in their locker, their boots wouldn't be available after they took them off and went to bed when they got up in the morning.

"There'd be a notice on the noticeboard saying: 'Pair of boots held for ransom'. And the payment of one chocolate bar for the return of boots wasn't uncommon".

Maintenance of order and organisation is made much easier by the fact that should peer pressure fail to bring someone into line, there is the possibility of formal discipline later on.

As he looks towards retirement and spending more time on another type of boat, a narrowboat in the north of England, Neve plans to keep in touch with those he served with via the busy schedule of reunions the service organises.

But there'll be no more inescapable small spaces or lack of privacy even if the memories of the "coffins" linger.

"I will miss it," he says.

More from the Magazine

Image copyright Getty Images

The UK has some of the smallest new homes in Europe. So how can people cope living in a small space?

A life lived in tiny spaces (April 2013)

Hear more about living on a submarine from Lt Cmdr Charlie Neve in The Why Factor: Why Do Humans Need So Much Space? on the BBC World Service at 18:32 GMT on 11 September - or listen on BBC iPlayer Radio

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