How long will damp take to dry out?
 

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

regards,
Andrew

In article ,
"Andrew" - says...
Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

Unless you rendered with lime mortar and painted with a porous paint it
quite possibly won't go away at all.

If you have eliminated the source it can take along time to dry out
e.g. year or more. Also old lime plaster if damp for a long period can
become hygroscopic i.e. absorb atmospheric moisture. This results in
intermittent damp patches in peculiar places e.g. half way up walls,
and is most noticeable in humid weather like today or when there is a
change from cool to warm/humid.
So give it a year or so.

cheers

Jacob

Rob Morley wrote:
In article ,
"Andrew" - says...

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.


Unless you rendered with lime mortar and painted with a porous paint it
quite possibly won't go away at all.

I'm sure the OP will be pleased to hear that! Unless he runs a laundry
and has no heating, I'm sure the damp will dry out just fine since it
will presumably no longer be pouring through from outside.

Where do you find these plasterers that are prepared to bugger about
covering whole walls with wet sacks? Do they smoke clay pipes?
And what the hell use is porous paint? All water based paint is porous,
as you soon discover if you use it to cure penetrating damp. Pliolite
resins are a *major* improvement in masonry paint but even they are far
from being impermeable.

"Stuart Noble" wrote in message
...
Rob Morley wrote:
In article ,
"Andrew" - says...

Just had the exterior of a Victorian house repainted/re-rendered. The
solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.


Unless you rendered with lime mortar and painted with a porous paint it
quite possibly won't go away at all.

I'm sure the OP will be pleased to hear that! Unless he runs a laundry
and has no heating, I'm sure the damp will dry out just fine since it
will presumably no longer be pouring through from outside.


Mention damp and period buildings on the internet and you can guarantee an
instant if-it's-not-lime-your-doomed response. Apart from for really old
buildings,
I've never come across builders in the real world even mention the stuff.

As my house has had a concrete render for least 100 years, replacing it all
with lime seems overkill and probably unnecessary, even if it was an option.
If the damp doesn't dry out, I'll just paint over it and manage the problem.
However, from the responses received I guess I should wait a few months
to see if the problem is cured.

regards,
Andrew

In article ,
"Andrew" - says...

"Stuart Noble" wrote in message
...
Rob Morley wrote:
In article ,
"Andrew" - says...

Just had the exterior of a Victorian house repainted/re-rendered. The
solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.


Unless you rendered with lime mortar and painted with a porous paint it
quite possibly won't go away at all.

I'm sure the OP will be pleased to hear that! Unless he runs a laundry
and has no heating, I'm sure the damp will dry out just fine since it
will presumably no longer be pouring through from outside.


Mention damp and period buildings on the internet and you can guarantee an
instant if-it's-not-lime-your-doomed response.

I was surprised I was the only one - someone has to do it, it's
traditional :-)

Andrew wrote:

Just had the exterior of a Victorian house repainted/re-rendered. The
solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.

You never told us what you did to solve the damp problem. If
rerendering was it, it may or may not dry out, its not really a good
solution to damp.


NT

In article ,
says...
wrote:
Andrew wrote:


Just had the exterior of a Victorian house repainted/re-rendered. The

solid

walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.


You never told us what you did to solve the damp problem. If
rerendering was it, it may or may not dry out, its not really a good
solution to damp.


It's often the only solution short of re-building the house. If water is
prevented from entering the wall from the outside, why wouldn't the
inside dry out?

Because moisture also comes from inside and below?

Rob Morley wrote:
In article ,
says...

wrote:

Andrew wrote:



Just had the exterior of a Victorian house repainted/re-rendered. The

solid


walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.


You never told us what you did to solve the damp problem. If
rerendering was it, it may or may not dry out, its not really a good
solution to damp.


It's often the only solution short of re-building the house. If water is
prevented from entering the wall from the outside, why wouldn't the
inside dry out?


Because moisture also comes from inside and below?

Lime lovers seem to have the idea that human activity generates buckets
of water that are prevented from evaporating by cement and/or a coat of
Dulux on the outside of the house. With normal heating and ventilation
this source of moisture shouldn't be an issue. If water is entering from
below then you need to stop it rather than accommodating damp as a way
of life. It really isn't very healthy

I hate to be a wet blanket, but bear with me for a while.
..
In 1994 I replaced a coal boiler with a gas combi. In 1999
water was running down the living room wall. After eliminating
the obvious candidates, slates, flaunching, pointing, flashing
etc I was left with only one option - the flue (the products of
combustion are carbon dioxide and water). This proved to be the
case. It had been damaged on installation and, for five years had
been pumping water into a 75cm shale wall with soil/lime mortar.
The flue was replaced.
..
Six years on, the wall is still not completely dry despite my having,
this year, chopped off and repointed the bottom metre of external
rendering and run a 2kw fire and a dehumidifier in the sealed room for
8 - 10 hours a day.
..
Another side effect (this is speculation)is that the formerly sound
rendering has been loosened by winter frost action on the moisture in
the wall, so I may have to replace this as well.
..
The moral of this story is to assume nothing about the behaviour of
damp. All you can do is find its source, block it, do what you can to
dry it, then wait, wait, wait.
..
The mystery, to me, is why, in this age of technological wizardry, when
probes can be landed on other planets and the evolution of a life can
be tracked from ejaculation to delivery, there is no simple hand held
device which, either electronically or seismologically, can detect the
precise location of moisture in a wall. Moisture meters are a nonsense:
they tell you what you can see or, by running your hand over the wall,
feel, but tell you nothing (without drilling) about what is happening
within it.

Tony.

On 10 Sep 2005 12:24:47 -0700, wrote:

| I hate to be a wet blanket, but bear with me for a while.
| .
| In 1994 I replaced a coal boiler with a gas combi. In 1999
| water was running down the living room wall. After eliminating
| the obvious candidates, slates, flaunching, pointing, flashing
| etc I was left with only one option - the flue (the products of
| combustion are carbon dioxide and water). This proved to be the
| case. It had been damaged on installation and, for five years had
| been pumping water into a 75cm shale wall with soil/lime mortar.
| The flue was replaced.
| .
| Six years on, the wall is still not completely dry despite my having,
| this year, chopped off and repointed the bottom metre of external
| rendering and run a 2kw fire and a dehumidifier in the sealed room for
| 8 - 10 hours a day.
| .
| Another side effect (this is speculation)is that the formerly sound
| rendering has been loosened by winter frost action on the moisture in
| the wall, so I may have to replace this as well.
| .
| The moral of this story is to assume nothing about the behaviour of
| damp. All you can do is find its source, block it, do what you can to
| dry it, then wait, wait, wait.
| .
| The mystery, to me, is why, in this age of technological wizardry, when
| probes can be landed on other planets and the evolution of a life can
| be tracked from ejaculation to delivery, there is no simple hand held
| device which, either electronically or seismologically, can detect the
| precise location of moisture in a wall. Moisture meters are a nonsense:
| they tell you what you can see or, by running your hand over the wall,
| feel, but tell you nothing (without drilling) about what is happening
| within it.
|
| Tony.

--
Dave Fawthrop dave hyphenologist co uk
"Intelligent Design?" my knees say *not*.
"Intelligent Design?" my back says *not*.

How the hell did Dave Fawthrop become the author of my post? I bet he's
wondering too.

Tony.

On 10 Sep 2005 12:24:47 -0700, wrote:

In 1994 I replaced a coal boiler with a gas combi. In 1999
water was running down the living room wall. After eliminating
the obvious candidates, slates, flaunching, pointing, flashing
etc I was left with only one option - the flue (the products of
combustion are carbon dioxide and water). This proved to be the
case. It had been damaged on installation and, for five years had
been pumping water into a 75cm shale wall with soil/lime mortar.
The flue was replaced.
.
Six years on, the wall is still not completely dry despite my having,
this year, chopped off and repointed the bottom metre of external
rendering and run a 2kw fire and a dehumidifier in the sealed room for
8 - 10 hours a day.

Are you sure you don't have another source of damp?

DG

In article .com,
says...
How the hell did Dave Fawthrop become the author of my post? I bet he's
wondering too.

He didn't, although he has apparently reposted it in its entirety
without adding any of his own comments. Do you understand how quoting
and attributions work on Usenet?

On 10 Sep 2005 12:52:19 -0700, wrote:

| How the hell did Dave Fawthrop become the author of my post? I bet he's
| wondering too.

If you look you will find that I quoted it.
I was going to follow up and hit the wrong button :-(
--
Dave Fawthrop dave hyphenologist co uk
"Intelligent Design?" my knees say *not*.
"Intelligent Design?" my back says *not*.

In article ,
Dave Fawthrop wrote:
If you look you will find that I quoted it.
I was going to follow up and hit the wrong button :-(

A decent newsreader should then throw up a warning of 'no unquoted text'
and ask for confirmation. ;-)

--
*60-year-old, one owner - needs parts, make offer

Dave Plowman London SW
To e-mail, change noise into sound.

Are you sure you don't have another source of damp?

Yes. The water was trapped between internal (which had been plastered
over) and external rendering and it was simply hydrostatic pressure
that eventually forced it into the house. In any case, unlesss every
cat for 50 miles is climbing on my roof, nightly, to urinate on the
rendering (I think I'd have noticed (:- ) rain is the only possible
source - and we've had very little of that in this area in the last 2
or 3 years. But if you have a credible alternative, I'm listening. The
novelty of bare plaster in the living room is beginning to pall.

Tony.

On 11 Sep 2005 08:06:20 -0700, wrote:

Are you sure you don't have another source of damp?

Yes. The water was trapped between internal (which had been plastered
over) and external rendering and it was simply hydrostatic pressure

A 75 cm thick wall full of water ? :((

that eventually forced it into the house. In any case, unlesss every
cat for 50 miles is climbing on my roof, nightly, to urinate on the
rendering (I think I'd have noticed (:- ) rain is the only possible
source - and we've had very little of that in this area in the last 2
or 3 years. But if you have a credible alternative, I'm listening. The
novelty of bare plaster in the living room is beginning to pall.


How much does the dehumidifier collect in it's 8 hour session?

Noticing that my vacuum foodsealer sucks moisture vigorously out of
stuff such as onions I wonder if sealing the area with a visqueen
membrane using flexible RTV and vacuum pumping it out with an
aspirator (killing 2 birds with one stone) might work?

http://en.wikipedia.org/wiki/Aspirator

http://hyperphysics.phy-astr.gsu.edu...ids/aspir.html

Be Careful ! see pics...

Possible snag, onions are of course compressible walls are not. But if
the wall is permeable enough it might be worth a try.

I want a Nobel prize if it works.

DG

How much does the dehumidifier collect in it's 8 hour session?

About 3 pints. The arithmetic is, to me at least, interesting.

The wall has a total volume of about 1,814, 400 cu in, and the split in
the flue was near the top, so the whole wall was soaked. If 10% were
water and it dried in 6 years (2190 days) it would mean that
181440/2190 cu in would have to be released, on average, daily i.e.
2.4pts which, taking into account atmospheric moisture ( the windows
are open for the other 14-16 hours) and the fact that the dehumidifier
and heating have accelerated the process recently, is not too far from
what I was getting.

A curious feature, which supports my contention that the water is
trapped between the 2 coats of render, is that turning off the
dehumidifier, during the last week or so, causes the internal wall to
become drier, leaving gravity, and the air, working on the newly
exposed lower part of the outside, to take over the drying. When the
dehumidifier is on, the resultant dry atmosphere, internally, causes
moisture to be drawn into the house.

Of course, this is all ifs buts and maybes, but I'm fairly confident
that my reasoning is sound, even if the estimates are no more than
guesses, and a little less confident that the end is in sight. Please
God, don't make it more than 10%(:-

Tony/

I would check the property
over for all the usual causes of damp.

See paragraph 2 of my post on September 10th. That's where I started,
and have checked since.

Tony.

I can't see that it's possible to "trap" water between 2 coats of
something permeable. But if water pours in at a specific point when it
rains and then has to dry out gradually by evaporation, the wall may
well give the impression of being permanently soaked.

I was using the word 'trap' loosely. The wall is enclosed by 4:1
cement render. In this part of the world just about everything is a 4:1
mix. I didn't put it there, nor would I have, but I've learned from
experience that the locals have their own way of doing things, based on
their experience.

As I said previously, we've had little rain for a long time but, when
it happens, the wall gets no wetter.

Tony.

How long will damp take to dry out?
 

replying to Rob Morley, Master maz wrote:
Yeah if its built with soft stone. No need for lime mortar and porous paint
everytime

--
for full context, visit https://www.homeownershub.com/uk-diy...ut-190549-.htm

How long will damp take to dry out?
 

replying to Rob Morley, Master maz wrote:
Yeah if it’s built with soft stone. No need for lime mortar and porous paint
everytime


In other news:

In depth: the major events of 2005
Election 2005. The beginning of the year saw the re-election of Tony
Blair's Labour government for a historic third term. ...
VE/VJ day 60 year on. Sixty years ago this year the largest conflict
in history came to an end. ...
Tory leadership. ...
London bombings. ...
Bird Flu. ...
Hurricane Katrina. ...
Trafalgar 200.

--
Graham.

%Profound_observation%

How long will damp take to dry out?
 

On Wednesday, 7 September 2005 12:41:02 UTC+1, Andrew wrote:
Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.


Speed things up.
Get yourself a dehumidifier.
Be sure to keep the room sealed when it is running.

How long will damp take to dry out?
 

On Wednesday, 20 March 2019 07:50:30 UTC, harry wrote:
On Wednesday, 7 September 2005 12:41:02 UTC+1, Andrew wrote:

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

exterior waterproof coatings don't normally help a damp situation on old houses

Speed things up.
Get yourself a dehumidifier.
Be sure to keep the room sealed when it is running.

the damp is on all levels, it would be better not to seal the room.


NT

How long will damp take to dry out?
 

On Wednesday, 20 March 2019 11:05:05 UTC, wrote:
On Wednesday, 20 March 2019 07:50:30 UTC, harry wrote:
On Wednesday, 7 September 2005 12:41:02 UTC+1, Andrew wrote:

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

exterior waterproof coatings don't normally help a damp situation on old houses

Speed things up.
Get yourself a dehumidifier.
Be sure to keep the room sealed when it is running.

the damp is on all levels, it would be better not to seal the room.


Not when you're running a dehumidfier.
You don't want to be dehumidifying the great outdoors.

How long will damp take to dry out?
 

On Wednesday, 20 March 2019 13:23:05 UTC, harry wrote:
On Wednesday, 20 March 2019 11:05:05 UTC, tabby wrote:
On Wednesday, 20 March 2019 07:50:30 UTC, harry wrote:
On Wednesday, 7 September 2005 12:41:02 UTC+1, Andrew wrote:

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

exterior waterproof coatings don't normally help a damp situation on old houses

Speed things up.
Get yourself a dehumidifier.
Be sure to keep the room sealed when it is running.

the damp is on all levels, it would be better not to seal the room.


Not when you're running a dehumidfier.
You don't want to be dehumidifying the great outdoors.

Most of us use dehumidifiers indoors. And most houses have the windows closed in the middle of winter. Is this really worth discussing? No.


NT

How long will damp take to dry out?
 

On Thursday, 21 March 2019 01:53:26 UTC, wrote:
On Wednesday, 20 March 2019 13:23:05 UTC, harry wrote:
On Wednesday, 20 March 2019 11:05:05 UTC, tabby wrote:
On Wednesday, 20 March 2019 07:50:30 UTC, harry wrote:
On Wednesday, 7 September 2005 12:41:02 UTC+1, Andrew wrote:

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

exterior waterproof coatings don't normally help a damp situation on old houses

Speed things up.
Get yourself a dehumidifier.
Be sure to keep the room sealed when it is running.

the damp is on all levels, it would be better not to seal the room.


Not when you're running a dehumidfier.
You don't want to be dehumidifying the great outdoors.

Most of us use dehumidifiers indoors. And most houses have the windows closed in the middle of winter. Is this really worth discussing? No.


NT

Well, you made the silly remark.

How long will damp take to dry out?
 

On Thursday, 21 March 2019 07:45:07 UTC, harry wrote:
On Thursday, 21 March 2019 01:53:26 UTC, tabby wrote:
On Wednesday, 20 March 2019 13:23:05 UTC, harry wrote:
On Wednesday, 20 March 2019 11:05:05 UTC, tabby wrote:
On Wednesday, 20 March 2019 07:50:30 UTC, harry wrote:
On Wednesday, 7 September 2005 12:41:02 UTC+1, Andrew wrote:

Just had the exterior of a Victorian house repainted/re-rendered. The solid
walls
are about 450mm thick. There was penetrating damp on some of the inside
wall.
These walls are still damp but we assume that it will take some time for the
the
brickwork to dry out. (In fact some of the internal damp seems to have got
worse - probably because it is now less easy for trapped damp it to escape
externally).

The building is about 15m high. Damp occurs at all levels. How long is
reasonable
to wait before we can expect the inside to be dry, assuming the source of
damp
has now been eliminated? The building is well ventilated and it is not
condensation.

exterior waterproof coatings don't normally help a damp situation on old houses

Speed things up.
Get yourself a dehumidifier.
Be sure to keep the room sealed when it is running.

the damp is on all levels, it would be better not to seal the room.


Not when you're running a dehumidfier.
You don't want to be dehumidifying the great outdoors.

Most of us use dehumidifiers indoors. And most houses have the windows closed in the middle of winter. Is this really worth discussing? No.


NT

Well, you made the silly remark.

Welcome to the filter.