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The Natural Philosopher

wrote:
The Natural Philosopher wrote:

The more I look at the average urban and suburban sprawl the more I feel
that actually what we should be doing is putting the roads deep down,
the houses just under the surface with light pipes and the gardens and
parks on top...Hobbiton? possibly :-)

What do you think are the pros and cons of this from a cost/benefit
environmental and general living feeling?

First of all thanks for contributing some excellent points.

This has been suggested as an approach to dealing with much higher
population levels in future. You can have much higher density housing
below the surface yet retain a green countryside appearance above. You
can have fields orchards and houses occupying the same space. If on
todays housing estates houses occupy 1/3 or 1/4 the area, underground
they could occupy almost 100%, tripling or quadrupling density.

They said the same of tower blocks too..

The biggest problem is cost. Building a house underground requires a
far stronger structure than one on the ground. There are also
additional costs such as soundproofing for houses under roads,
drainage, fire escapes, climate control, etc.

Now, lets get detailed on that.

Does it need to be stronger? Some yes obviously, but I am not thinking
of a house 400 foopt down,. just 4 ft down..maintaining enough topsoil
to have an insulating and organic production layer above. Plenty of roof
gardens are built on unamplifed structures..

Soundproofing. Yes. I accept that, but the roads would be deeper
underground, and nothing proofs as well as soil IME..vibration, not
sound would, I suspect,. be a greater issue.

Drainage is not an issue..as long as there is somewhere deeper to drain
TO - and there would be - this is 'cut and cover' not tunnelling - I dio
not see a huge problem.

Climate control I feel is easy. 4ft of soil is going to be a damn good
insulator and a fairly massive block or concrete structure will equalize
temperatures hugely.

Heat exchangers and judicious use of insulation OUTSIDE the
structure..so that its both protected from soil movement and retains
good thermal mass inside - should make it almost free of heating needs
at all. Compared with the copious amounts of celotex and rockwool,. 4ft
of earth on a polystyrene block is cheap..

Fire escapes are definititely an issue, however climbing up a flight of
stairs rather than jumnping out of a window is no worse..

The requirement for window area also means that above ground wont be
clutter free, and cant be used like a ploughed field. It can however be
used for some growing applications.

That was never the intention. I envisaged say 6ft tall pipes with galss
tops..above 'peering' height for provacy..

And maybe perisocopes. Also top plant trees on top for further climate
control.

The inability to look out the window is very undesirable to most
people, though periscope windows are a possibility.

Is it? Most people today spend more time peering into a TV/PC screen
than out of the window, and in an urban environment I have never ever
had a room with a decent view outside of extremeley expensive hotels and
apartments I have visited.

Tunnels are vastly more expensive than surface roads, and having roads
on the surface with houses underground would support far more
population than all on top as now.

I disagree with the 'vastly' bit. All roads need some earth moving, and
a road in a cutting is more a problem because the spoils have to be
physically removed..the further they have to go the worse it is. In this
case however one is talking about digging a trench for the access roads
and the services and then piling the material on top of the houses.
Not very expensive at all..cut and cocver tunneling is far less
expensive than real tunneling - where every cubic cm of spoil has to be
removed out of the whole current tunnel length.

My vision is that the surface is the place where cyclists and
pedestrians and dogs go, and trees and parks and so on. The houses are
just underneath and the roads and shops are a bit deeper.

In the distant future, as populatoin
rises even more, roads underground might become desirable too. Such
roadways could be on a different level than the housing, so one could
have separate fully packed layers of roads, housing, factories, and
basic services.

Yes..I just wanted to identify the costs and major technical problems
with this.

The fact is that major city right now pours billions of megawatt hours
into the sky and general environment. Putting a city underground would
reduce all of that..any stray heat from streetlights would be trapped
within the complex and contribute to warmer living space etc, as would
proper heat exchangers on e.g. exhaust fumes..a climate controlled CITY
with an eco area on top seems to me to be almost a no brainer..

Heck, you could build one on Mars...;-)

Lets say (havent checked figures now, just ballparking) that 5% of
British land is built on, and out of that the house occupies 33% of
that land. Converting to underground housing on 2 storeys would then
give us an increase in total housing area of around 60 times the
present house area.

Nearly everything comes down to cost in the end, and the cost of doing
this today on a mass scale is prohibitive. Its also not well enough
accepted to support good sale prices for such properties. It also
brings more disadvantage than advantage in reality, though when
populations are 50x as large it may be the other way round.

I am not so sure the costs are as prohibitive as you might think.

However there would be extreme issues with making it a small scale
build. It has to be done on a whole neighborhood, or by a wealthy
individual as a quirky 'grand design'..what a Phd project for an
architecture graduate in conjunction with a civil engineer..design and
cost an underground city..

NT