On Fri, 19 Aug 2011 01:20:55 -0700, CJB wrote:

tl;dr: there was a lot of rain in a short period, some buildings that
cover a lot of area don't have enough drainage on their roofs to cope.

Roofs are generally designed such that normal levels of rainfall are
carried away by pipes. However, these pipes have a capacity limit, and
can be blocked by all sorts of debris that ends up on the roofs.

When that happens, and you then get an unusually high level of rainfall
over a short period, it's not unusual for certain types of roof to start
letting in water, as it arrives faster than it can be removed.

For example, any tiled type roof with a gully between adjacent slopes
will leak if the water level in the gully rises far enough above the
gully lining.

This is just as true when the "tiles" are 8' x 4' sheets of corrugated
material as it is when they're 18" x 8" of slate.

Rgds

Denis McMahon

"Denis McMahon" wrote in message
.com...
On Fri, 19 Aug 2011 01:20:55 -0700, CJB wrote:

tl;dr: there was a lot of rain in a short period, some buildings that
cover a lot of area don't have enough drainage on their roofs to cope.

Roofs are generally designed such that normal levels of rainfall are
carried away by pipes. However, these pipes have a capacity limit, and
can be blocked by all sorts of debris that ends up on the roofs.

The area in question, above platform 12, isn't really a roof, it's the
underside of the old parcels deck, (the London St deck) which is currently
undergoing major work to convert it into the new taxi rank. To look at from
below it is more like the underside of an old style railway bridge, with
arched brick infill between girders. Perhaps the work on the deck above has
progressed to the stage where whatever waterproofing there was has been
removed - and they've been caught out by the heavy rain?

Paul S

On Aug 19, 3:30*pm, "Paul Scott"
wrote:
"Denis McMahon" wrote in message

.com...

On Fri, 19 Aug 2011 01:20:55 -0700, CJB wrote:

tl;dr: there was a lot of rain in a short period, some buildings that
cover a lot of area don't have enough drainage on their roofs to cope.

Roofs are generally designed such that normal levels of rainfall are
carried away by pipes. However, these pipes have a capacity limit, and
can be blocked by all sorts of debris that ends up on the roofs.

The area in question, above platform 12, isn't really a roof, it's the
underside of the old parcels deck, (the London St deck) which is currently
undergoing major work to convert it into the new taxi rank. *To look at from
below it is more like the underside of an old style railway bridge, with
arched brick infill between girders. *Perhaps the work on the deck above has
progressed to the stage where whatever waterproofing there was has been
removed - and they've been caught out by the heavy rain?

Paul S

Platform 12 has been dripping for years - even in dry weather. The
installation of a waterproof membrane seems to be beyond NR and its
contractors to install. Instead they seem to employ a gang of guys
with Rajneesh-cult-like orange overalls to sweep away the pools of
water. The trip mats are scattered along the platform, along with
numerous buckets with gauze over the top. And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

On Aug 24, 10:11*am, CJB wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Neil

On 24/08/2011 09:50, Neil Williams wrote:
On Aug 24, 10:11 am, wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Is there anywhere on the planet where the whole experience of arriving
by air gives a good impression?


--
Arthur Figgis Surrey, UK

On 25/08/2011 00:52, Arthur Figgis wrote:
On 24/08/2011 09:50, Neil Williams wrote:
On Aug 24, 10:11 am, wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Is there anywhere on the planet where the whole experience of arriving
by air gives a good impression?



White House helipad.

--
Graeme Wall
This account not read, substitute trains for rail.
Railway Miscellany at www.greywall.demon.co.uk/rail

On Thu, 25 Aug 2011 00:52:13 +0100, Arthur Figgis wrote:

On 24/08/2011 09:50, Neil Williams wrote:
On Aug 24, 10:11 am, wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Is there anywhere on the planet where the whole experience of arriving
by air gives a good impression?

Arlanda.
Gardermoen.
Copenhagen's pretty good, too.
Tromso, of course.

Hmm. A pattern starts to emerge..

--
From the Model M of Andy Breen, speaking only for himself

On Aug 25, 1:11*am, Andy Breen wrote:
On Thu, 25 Aug 2011 00:52:13 +0100, Arthur Figgis wrote:
On 24/08/2011 09:50, Neil Williams wrote:
On Aug 24, 10:11 am, *wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Is there anywhere on the planet where the whole experience of arriving
by air gives a good impression?

Arlanda.
Gardermoen.
Copenhagen's pretty good, too.
Tromso, of course.

Omaha, NE is not bad.

On 25/08/2011 09:11, Andy Breen wrote:
On Thu, 25 Aug 2011 00:52:13 +0100, Arthur Figgis wrote:

On 24/08/2011 09:50, Neil Williams wrote:
On Aug 24, 10:11 am, wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Is there anywhere on the planet where the whole experience of arriving
by air gives a good impression?

Arlanda.

Don't they rig the train service so you have to use airport trains at
inflated prices?

Gardermoen.

Not done that.

Copenhagen's pretty good, too.

OK, I guess so.

Tromso, of course.

Not done that.

Hmm. A pattern starts to emerge..



--
Arthur Figgis Surrey, UK

On Aug 25, 9:11*am, Andy Breen wrote:
On Thu, 25 Aug 2011 00:52:13 +0100, Arthur Figgis wrote:
On 24/08/2011 09:50, Neil Williams wrote:
On Aug 24, 10:11 am, *wrote:

And this is the main
platform for the Heathrow Connect - welcome to London hapless airline
tourists.

"You should have used Heathrow Express, you cheapskate"?

Is there anywhere on the planet where the whole experience of arriving
by air gives a good impression?

Arlanda.
Gardermoen.
Copenhagen's pretty good, too.
Tromso, of course.

Hmm. A pattern starts to emerge..

--
From the Model M of Andy Breen, speaking only for himself

Hmmm, where have I been by air (relatively) recently?

Vancouver's not bad. When I went there in 2004, you had to get an
(expensive-ish) bus from the airport to downtown, but the area you
went through was quite pleasant.

Madeira airport's probably on the least attractive part of the island.

The train from Barcelona airport to the city centre goes through some
of the less-attractive suburbs.

The area you go through from New York JFK to Manhattan wasn't too bad,
if nothing special.

Can't comment on Vienna, as I went there by train - and the approach
from the W through the Wienerwald was rather nice.

Nick