We have a patio along a shared boundary wall that might, in the not so
distant future, fall over.

A wall further down did fall over and the time to clean up the bricks
etc was far less than it would have been to take down the wall by
hand, and of course, the cost to re-build was shared, whereas if I
take down the current leaner manually it won't be. So we wait.

Anyhow, the patio in question was getting into a bad state. Or at
least the last 4 meters of it was. It was constructed using, in
effect, another patio as a base, then some sand and finally very thin
tiles (less than half a centimeter thick X around 10 x 20 cm), many of
which were now broken, supported on splodges of sand-cement mix, which
had all but deteriorated in most places.

It's a heavy wall with a really heavy "capping". that means that if I
were to re-do the patio with some nice stone (for example) now, when
that wall comes down it'll damage it badly.
So I decided on a cheap repair option.

I removed all the collapsed area of the patio. Bagged up all those
flimsy tiles.
Removed the under-layer to the level of the "old" patio (which had
been made using concrete slabs on top of , well, just the soil)
Incorporated fresh cement into that old sand, (approx. 6Sd:1Cmt) mixed
thoroughly, returned to position and hammered it down using a purpose
built stomper.
Next day it was solid.
Then, getting 2 different types of sand and 3 different pigments I
proceeded to make my own slabs in various sizes, applying a key-stone
pattern, some with just one type of sand others, with a mix of the two
and same went for the dyes. 4 parts sand; 1 part cement

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

On 02/12/2010 11:03, aquachimp wrote:

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

I'll hazard a guess that the old stuff is higher density concrete slab
with a better heat conductivity and so very slightly warmer and sticky
for the snow when temperatures are sub zero for a prolonged time.

Thing to look for is next time it snows does the old stuff stay wet for
longer and then quickly build up whilst the new stuff still has loose
powder snow on it. My cast iron drain covers do something similar.

Regards,
Martin Brown

PS now 14" accumulated snow here in North Yorks and counting

"Martin Brown" wrote in message
...
On 02/12/2010 11:03, aquachimp wrote:

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

I'll hazard a guess that the old stuff is higher density concrete slab
with a better heat conductivity and so very slightly warmer and sticky for
the snow when temperatures are sub zero for a prolonged time.

Thing to look for is next time it snows does the old stuff stay wet for
longer and then quickly build up whilst the new stuff still has loose
powder snow on it. My cast iron drain covers do something similar.


A similar thing has happened on our slabs in the garden this morning.
Instead of the snow over the joints being lower as I would have expected,
it's noticeably higher. Here's a pic, hope it shows up OK

http://i163.photobucket.com/albums/t...f/02Dec012.jpg

Steve

On Dec 2, 2:58*pm, "shazzbat"
wrote:
"Martin Brown" wrote in message

...



On 02/12/2010 11:03, aquachimp wrote:

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

I'll hazard a guess that the old stuff is higher density concrete slab
with a better heat conductivity and so very slightly warmer and sticky for
the snow when temperatures are sub zero for a prolonged time.

Thing to look for is next time it snows does the old stuff stay wet for
longer and then quickly build up whilst the new stuff still has loose
powder snow on it. My cast iron drain covers do something similar.

A similar thing has happened on our slabs in the garden this morning.
Instead of the snow over the joints being lower as I would have expected,
it's noticeably higher. Here's a pic, hope it shows up OK

http://i163.photobucket.com/albums/t...20stuff/02Dec0...

Steve

Having made individual "slabs", I then pointed them up using the same
strength mix, but no pigment.
There is no variation as shows up clearly on your photo. Indeed a
curiosity.

BTW, the snow on the "old" patio is also higher, but looks fluffier.
What is under the rather small and thin tiles (I wouldn't even call
them slabs) of the "old" patio is a thin-ish layer of splodges of
concrete, which is deteriorating and the remainder is sand for about
20cm and then the concrete slabs. (I originally thought I had found an
old patio under the current one.
I did not remove that slab layer.

So, to comment on martins guess, the _old_ patio is NOT a higher
density concrete slab.
But the addition of cement into the sand that was there, along with
the making of concrete slabs would, I think, make that a fairly
uniform higher density concrete slab (no splodges on sand, under thin
little tiles

On Dec 2, 12:35*pm, Martin Brown
wrote:
On 02/12/2010 11:03, aquachimp wrote:

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

I'll hazard a guess that the old stuff is higher density concrete slab
with a better heat conductivity and so very slightly warmer and sticky
for the snow when temperatures are sub zero for a prolonged time.

Nice try, but it would be the newer section that has the higher
density of concrete.


Thing to look for is next time it snows does the old stuff stay wet for
longer

The snow is melting and the old patio looks decidely wetter;
I just looked again (it had started snowing again earlier, but seems
to have given up) and I can now see that the snow on the newer section
is also fading away, but uniformly, unlike the old patio section.
However, just as curiously, the joints are now whiter and slightly
higher looking; The mix for the joints was carefully measured, whilst
the mixture for the slabs was more guesstimated.

and then quickly build up whilst the new stuff still has loose
powder snow on it. My cast iron drain covers do something similar.

Regards,
Martin Brown

PS now 14" accumulated snow here in North Yorks and counting

On Dec 2, 4:33*pm, aquachimp
wrote:
On Dec 2, 12:35*pm, Martin Brown
wrote:



On 02/12/2010 11:03, aquachimp wrote:

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

I'll hazard a guess that the old stuff is higher density concrete slab
with a better heat conductivity and so very slightly warmer and sticky
for the snow when temperatures are sub zero for a prolonged time.

Nice try, but it would be the newer section that has the higher
density of concrete.



Thing to look for is next time it snows does the old stuff stay wet for
longer

The snow is melting and the old patio looks decidely wetter;
I just looked again (it had started snowing again earlier, but seems
to have given up) and I can now see that the snow on the newer section
is also fading away, but uniformly, unlike the old patio section.
However, just as curiously, the joints are now whiter and slightly
higher looking; The mix for the joints was carefully measured, whilst
the mixture for the slabs was more guesstimated.

and then quickly build up whilst the new stuff still has loose
powder snow on it. My cast iron drain covers do something similar.

Regards,
Martin Brown

PS now 14" accumulated snow here in North Yorks and counting

http://i56.tinypic.com/2rhw74l.jpg
http://tinypic.com/view.php?pic=2rhw74l&s=7
The nearer section being the older patio area.

On Dec 2, 5:03*pm, aquachimp
wrote:
On Dec 2, 4:33*pm, aquachimp
wrote:



On Dec 2, 12:35*pm, Martin Brown
wrote:

On 02/12/2010 11:03, aquachimp wrote:

The snow has exposed a curiosity. I took a photo, but it doesn't show
it adequately.

Where the snow had settled on the "new" area, the layer is thin.
Where the snow settled on the old area, it's noticeably thicker and
showing more signs of melting. That includes the areas of "old "patio
which I left intact to "frame" the new one, where the "old" was still
intact..

Anyone know why that might be.

I'll hazard a guess that the old stuff is higher density concrete slab
with a better heat conductivity and so very slightly warmer and sticky
for the snow when temperatures are sub zero for a prolonged time.

Nice try, but it would be the newer section that has the higher
density of concrete.

Thing to look for is next time it snows does the old stuff stay wet for
longer

The snow is melting and the old patio looks decidely wetter;
I just looked again (it had started snowing again earlier, but seems
to have given up) and I can now see that the snow on the newer section
is also fading away, but uniformly, unlike the old patio section.
However, just as curiously, the joints are now whiter and slightly
higher looking; The mix for the joints was carefully measured, whilst
the mixture for the slabs was more guesstimated.

and then quickly build up whilst the new stuff still has loose
powder snow on it. My cast iron drain covers do something similar.

Regards,
Martin Brown

PS now 14" accumulated snow here in North Yorks and counting

http://i56.tinypic.com/2rhw74l.jpghttp://tinypic.com/view.php?pic=2rhw74l&s=7
The nearer section being the older patio area.

I forgot to mention that there are two mats (plastic) to the right,
these appear to have even more snow also.