Hi,

My girlfriend and I are close to purchasing an end terrace house. we
know it has a few little problems like damp in the chimney breast
leading to some small patches of damp inside on and around the chimney
breast. we are going to open up all the flues (they are currently
blocked) and possibly have a coal fire in one room.

however, we visited the house the other day and noticed two small damp
patches on the outer gable end wall. the mortar between the stones is
quite wet and was coming away. My question is, can condensation from
the chimney soak outwards as well as inwards and if not, what are the
other explanations for this damp and is it easily fixed? if not the
chimney I'm thinking it might just be the old mortar is faulty and is
letting water soak into the bricks immediately around that area.

if I repoint this area and then paint the outer wall with a water
repeller will this prevent the condensation from gettin to the outside
naturally and concentrate the damp inside?

any help gratefully received

wrote:

Hi,

My girlfriend and I are close to purchasing an end terrace house. we
know it has a few little problems like damp in the chimney breast
leading to some small patches of damp inside on and around the chimney
breast. we are going to open up all the flues (they are currently
blocked) and possibly have a coal fire in one room.

however, we visited the house the other day and noticed two small damp
patches on the outer gable end wall. the mortar between the stones is
quite wet and was coming away. My question is, can condensation from
the chimney soak outwards as well as inwards and if not, what are the
other explanations for this damp and is it easily fixed? if not the
chimney I'm thinking it might just be the old mortar is faulty and is
letting water soak into the bricks immediately around that area.

if I repoint this area

may be all it needs. What age is the house? The materials determine the
right mortar to use.


and then paint the outer wall with a water
repeller

not such a good idea. Such chems only slow down evaporation, which does
the oposite of helping. Houses dont get damp if maintained
appropriately, theyre never painted with such things new, for sound
reason.


NT

It's a Victorain terrace. 1900-1905 I think. Stone walls.

wrote:
It's a Victorain terrace. 1900-1905 I think. Stone walls.

Photos (to be uploaded somewhere, there are lots of free places)? What
sort of stone, and approximately where?

wrote:
It's a Victorain terrace. 1900-1905 I think. Stone walls.

Right. Then you need to use lime mortar. Cement pulls the corners off
the stones when it eventually comes away. Also lime allows more
evaporation that cement, and ensures this evaporation (and thus
salting) occurs mostly on the easily replaced lime, not the stone.

Note lime mortar contains no cement, some seem confused about that!

Also note this is the wrong time of year to do outdoor lime work, as
frosts will cause it to fall apart if they occur. It would be best to
leave it till the risk of frost recedes, assuming things arent so dire
the wall is at risk of collapse.


NT

http://www.periodproperty.co.uk/cgi-...ing/forum2.pl?

Thanks for the replies.

Follow this link for a picture, click on "my hobbies" when you get to
the site.

http://kevin-richards.magix.net/

the damp patches are just under each arrow. the one on the left is
about a 0.5m circular patch and the one on the right is a bit smaller.
the chimney stack is between the two of them and you can judge the
floor level from the windows and wall at the front.

the rest of the wall seems bone dry, its just these two isolated
patches, literally like someones just spilt water on it in that one
spot. the mortar was crumbling as I rubbed it though.

our main reason to worry is that the original sale of the house fell
through becasue the original buyer got a builder round who quoted for
£5000 worth of work. our builder (and friend) said pretty much nothing
needed doing to it and this other builder must have just been short of
work!! we missed these damp patches until the other day though. I know
it's difficult to say but do you think this random £5k could be
anything to do with these patches?

On 28 Jan 2006 08:35:55 -0800, "
wrote:

Hi,

My girlfriend and I are close to purchasing an end terrace house. we
know it has a few little problems like damp in the chimney breast
leading to some small patches of damp inside on and around the chimney
breast. we are going to open up all the flues (they are currently
blocked) and possibly have a coal fire in one room.

however, we visited the house the other day and noticed two small damp
patches on the outer gable end wall. the mortar between the stones is
quite wet and was coming away. My question is, can condensation from
the chimney soak outwards as well as inwards and if not, what are the
other explanations for this damp and is it easily fixed? if not the
chimney I'm thinking it might just be the old mortar is faulty and is
letting water soak into the bricks immediately around that area.

if I repoint this area and then paint the outer wall with a water
repeller will this prevent the condensation from gettin to the outside
naturally and concentrate the damp inside?

any help gratefully received

I have a half built chinmey, rain gets in the top, reaches an
obstruction, and runs out to the brickwork, you can see the water on
the bricks matches the height of the obstruction.

It may be as simple as this, especially if its an open pot on the top,
and a bad job of riping out an old fireplace.

Over time this wet in the bricks will damage the mortar, which can be
repointed.

Rick

wrote:

Follow this link for a picture, click on "my hobbies" when you get to thesite.
http://kevin-richards.magix.net/

You really pushed the boat out with all those photos didn't you!

Our main reason to worry is that the original sale of the house fell through because the
original buyer got a builder round who quoted for £5000 worth of work. Our builder (and
friend) said pretty much nothing needed doing to it and this other builder must have just
been short of work!

What are the joists like around the chimney? There may be damp coming
in as well as what you have seen on the outside.

We missed these damp patches until the other day though. I know it's difficult to say
but do you think this random £5k could be anything to do with these patches?

That would depend on what else you missed. Is your friend insured the
way a surveyor is? And watch for dodgy get-out clauses in the
surveyor's report.

You are going to need to get up on the chimney somehow and make sure
that there is no debris filling it after all those years of neglect.
Also check if it has a flue liner and when that was fitted if they use
it for C/H.

Relining a chimney and repointing the gable, plus scaffold (and topping
the chimney?) will take a big lump out of 5K. But times are a bit thin.
They always are after Sickmess.

£5000 implies £500 for materials. Thus after other expenses such as
scaffold and tool hire, he had found £3500 to £4000 worth of work.
That's quite a few days. How much was he allowing himself for rainy
days?

You will only find out if you bite the bullet. But your biggest problem
is only scaffolding that gable and sealing the chimney. You might
easily manage it yourself -in case I have put you off. But it is really
a summer time job for a DIYer.

(Of course if you believe in evolution you could hit it with lightning
indefinitely. It's not even organic. Hmmm.... how come there are no
fossil houses? Or pre-houses?)

wrote:

Thanks for the replies.

Follow this link for a picture, click on "my hobbies" when you get to
the site.

http://kevin-richards.magix.net/

a blank black flash box. How useful.

Theres no way we can know what else needs doing without seeing
anything, or surveying the house. You had a survey I assume?


NT

wrote:
wrote:


Thanks for the replies.

Follow this link for a picture, click on "my hobbies" when you get to
the site.

http://kevin-richards.magix.net/


a blank black flash box. How useful.

I can view the picture ok.

Sorry about the pictures. Was in a rush and it was the only place I
could find. if anyone can suggest a better free site for uploading pics
please let me know and I'll put some better ones up.

we did have a survey. it identified small patches of damp internally in
the chimney breast but that was it. bascially said everything else was
in good condition for its age.

builder looked at the joists for the chimney and said they looked fine.
chimney stack itself is fine.

It's difficult to say from your photograph but, a likely explanation of
your damp patches is that they are being caused as a result of the
burning of fossil fuels, which has made the stonework in that
particular area hygroscopic. Naturally, they will then absorb
moisture at a far greater rate than masonry that doesn't have these
characteristics.

Ammonium salts are produced when coal and wood is burned and these
leech into the surrounding masonry. That's why chimneybreasts often
show damp patches.

You can't do much about it now and, if the only problem is damp patches
on the external wall, which will dry out as the relative humdity falls
and evaporation kicks in, then I would just accept the fact that you
have two damp patches on your wall!

They won't be a recent thing and if they haven't done any damage by
now, chances are they aren't going to. As Meeow says, re-point with
lime morter and don't use anything on the surface that would inhibit
evaporation. Have a look at
http://www.pdoyle.net/It_is_rude_to_point.html

It will show you why you need lime instead of sand and cement!

HTH

Patrick

wrote in message
oups.com...
Sorry about the pictures. Was in a rush and it was the only place I
could find. if anyone can suggest a better free site for uploading pics
please let me know and I'll put some better ones up.


http://www.angelfire.lycos.com/ and its free



-

OK, been back to look at this. the damp patches on the outside gable
end wall correspond with a damp patch in the back room. It extends from
the lower right of the chimney breast to about half way acorss the
right hand alcove and is quite damp.

if the mortar has perished on the outside which I have concluded it
has, could the damp have permeated through to the inside and if so, is
this still a matter of just re-pointing the outside and obviously
putting right any damage on the inside?

could this be caused a by a fault in the damp course and if so could I
claim on this as it has a 30 year guarantee?

wrote:
OK, been back to look at this. the damp patches on the outside gable
end wall correspond with a damp patch in the back room. It extends from
the lower right of the chimney breast to about half way acorss the
right hand alcove and is quite damp.

if the mortar has perished on the outside which I have concluded it
has, could the damp have permeated through to the inside and if so, is
this still a matter of just re-pointing the outside and obviously
putting right any damage on the inside?

Suck it and see. Try repointing and see if it improves. IME it's likely
the bricks themselves are too porous in that area (the previous comment
about burning fossil fuel makes sense), so the next thing to try might
be a water repellant like Thomsons Waterseal. It's never worked for me
but you obviously don't want to obscure such nice brickwork in any way.

Are you sure rainwater isn't pouring on to those spots from somewhere.
Worth getting out there next time it pours to see if anything untoward
is happening. I have a gable end wall and it appears water divides into
2 streams either side of the breast rather than running down uniformly


could this be caused a by a fault in the damp course and if so could I
claim on this as it has a 30 year guarantee?


Worth a try. A metre up is supposedly the limit of rising damp, and it
looks like yours is well within that. If it isn't rising damp, then the
company's original diagnosis must have been wrong but I've never known
anyone succesfully claim against a damp company.
Keep us posted.

wrote:
I have just read this chain and have the following comments. A
Waterseal product will do exactly what it says on the tin and seal in
the water. The trouble with this is that the water may freeze durign
the winter and you will suffer terrible damage to the brickwork. I have
done a lot of research intot his common problem and can recommend three
products. All three are from a company called Chem Crete in the States,
but are imported to the UK. They are called Pavix, Yufix and Sofix.
They are water based repellants and sealers which allow the passage of
water vapour out of the brickwork but not in.

A one way sealer eh? Ain't technology amazing!

wrote:
Stuart Noble wrote:

wrote:

I have just read this chain and have the following comments. A
Waterseal product will do exactly what it says on the tin and seal in
the water. The trouble with this is that the water may freeze durign
the winter and you will suffer terrible damage to the brickwork. I have
done a lot of research intot his common problem and can recommend three
products. All three are from a company called Chem Crete in the States,
but are imported to the UK. They are called Pavix, Yufix and Sofix.
They are water based repellants and sealers which allow the passage of
water vapour out of the brickwork but not in.

A one way sealer eh? Ain't technology amazing!


I presume he means water vapour out but not water droplets in. A bit
like a Goretex jacket for the wall.

I still wouldn't trust it.

MBQ


I know the Gortex argument from way back. Microporous paints and all
that 70s stuff. Fact is, all paint will allow water laden air through
it, especially when applied to a porous and variable surface like
masonry where it doesn't form a proper film.
The idea that you can hermetically seal a buiding with a pot of paint is
faintly ridiculous. You're lucky if it even acts as a barrier to the
droplets.

Stuart, please see the trade lit below. I have used this sytem to water
proof a brickwork viaduct in London and 18 months later the arches are
still dry and let out to tennants without a problem. Things have moved
on from micro porous paints. Through my work with London Underground
maintainers Metronet Rail, I have seen the use of these products grow
quite quickly and are now being introduced as standard to new build and
maintenance works. The worst product for external masonry is a surface
sealer as it cannot protect against freeze thaw and transmission of
vapour through the substrate.

Chem-Crete SofiX CCC700 is a unique one of a kind water-based
crystallisation product specifically designed to permanently block
moisture and vapour transmission in concrete or masonry structures up
to 16 lb./1000 ft2/24 Hours. Application of the SofiX CCC700 system
blocks moisture and vapour movement through concrete and masonry
substrates within 24 hours. The Chem-Crete SofiX CCC700 can be easily
applied by spraying or rolling. Chem-Crete SofiX CCC700 is designed to
be applied to concrete substrates that are 7 days or older. The
Chem-Crete SofiX CCC700 is formulated to enhance deep penetration into
the concrete substrate through capillary action. The product components
migrate deep into the concrete substrate while reacting to form a
hygroscopic and hydrophilic crystalline material which permanently
blocks the concrete and masonry substrate pores. Even under the
influence of constant hydrostatic pressure, the crystallization
continues to fill and block the migration of moisture through the
concrete substrate. The crystallisation activity of the SofiX CCC700
system is continuous while moisture is present. The product becomes
inactive during dry conditions and is fully reactivated when moisture
or moisture vapor are present. The unique "reactivation" is the key in
providing permanent waterproofing protection for any concrete or
masonry substrate.
Chem-Crete SofiX CCC700 is an odourless, colourless, clear liquid with
very low viscosity that allows it to penetrate deeply into a concrete
substrate or other masonry products. The product protects, preserves
and waterproofs without any surface film formation or colour change.

wrote:

Stuart, please see the trade lit below. I have used this sytem to water
proof a brickwork viaduct in London and 18 months later the arches are
still dry and let out to tennants without a problem.

snip explanation

Better than Stuart's approach, but dont you think the best bet is to
just let the building work correctly in the first place? The great
majority of damp old buildings are damp because they have been modified
inappropriately, whether by accident or intent. Common causes of damp
are blocked underfloor vents, external cement render, cement pointing,
use of masonry paints and so on.

Some certainly are damp by design, but theyre are a very small minority
imho. The problem is simply the general lack of understanding how old
buildings handle damp, leading to suggestions like trying to waterproof
the wall, and explanations like 'the bricks are porous.'

Lack of maintenance is also a common issue, sometimes causing
penetrating damp from blocked gutters and downpipes, rusted through
downpipes, blocked drains etc.


NT

The message .com
from contains these words:

Lack of maintenance is also a common issue, sometimes causing
penetrating damp from blocked gutters and downpipes, rusted through
downpipes, blocked drains etc.

Or - like our old house in Hounslow - the environment was soggy. I once
lifted the downstairs floorboards for something and the soil beneath
wasn't just damp it was wringing wet. Glad we only rented it!

--
Skipweasel
Pay no attention to the man behind the curtain.

wrote:
Stuart, please see the trade lit below. I have used this sytem to water
proof a brickwork viaduct in London and 18 months later the arches are
still dry and let out to tennants without a problem. Things have moved
on from micro porous paints. Through my work with London Underground
maintainers Metronet Rail, I have seen the use of these products grow
quite quickly and are now being introduced as standard to new build and
maintenance works. The worst product for external masonry is a surface
sealer as it cannot protect against freeze thaw and transmission of
vapour through the substrate.

Chem-Crete SofiX CCC700 is a unique one of a kind water-based
crystallisation product specifically designed to permanently block
moisture and vapour transmission in concrete or masonry structures up
to 16 lb./1000 ft2/24 Hours. Application of the SofiX CCC700 system
blocks moisture and vapour movement through concrete and masonry
substrates within 24 hours. The Chem-Crete SofiX CCC700 can be easily
applied by spraying or rolling. Chem-Crete SofiX CCC700 is designed to
be applied to concrete substrates that are 7 days or older. The
Chem-Crete SofiX CCC700 is formulated to enhance deep penetration into
the concrete substrate through capillary action. The product components
migrate deep into the concrete substrate while reacting to form a
hygroscopic and hydrophilic crystalline material which permanently
blocks the concrete and masonry substrate pores. Even under the
influence of constant hydrostatic pressure, the crystallization
continues to fill and block the migration of moisture through the
concrete substrate. The crystallisation activity of the SofiX CCC700
system is continuous while moisture is present. The product becomes
inactive during dry conditions and is fully reactivated when moisture
or moisture vapor are present. The unique "reactivation" is the key in
providing permanent waterproofing protection for any concrete or
masonry substrate.
Chem-Crete SofiX CCC700 is an odourless, colourless, clear liquid with
very low viscosity that allows it to penetrate deeply into a concrete
substrate or other masonry products. The product protects, preserves
and waterproofs without any surface film formation or colour change.


Sounds like silicates. Hardly new, and hardly unique. But, if you've
used the product and it works, it has to be taken seriously.

wrote:
wrote:


Stuart, please see the trade lit below. I have used this sytem to water
proof a brickwork viaduct in London and 18 months later the arches are
still dry and let out to tennants without a problem.


snip explanation

Better than Stuart's approach, but dont you think the best bet is to
just let the building work correctly in the first place?


The great
majority of damp old buildings are damp because they have been modified
inappropriately, whether by accident or intent. Common causes of damp
are blocked underfloor vents, external cement render, cement pointing,
use of masonry paints and so on.

Some certainly are damp by design, but theyre are a very small minority
imho. The problem is simply the general lack of understanding how old
buildings handle damp, leading to suggestions like trying to waterproof
the wall, and explanations like 'the bricks are porous.'

Lack of maintenance is also a common issue, sometimes causing
penetrating damp from blocked gutters and downpipes, rusted through
downpipes, blocked drains etc.


NT


So I wonder which category this railway arch comes under.
If these products prevent the passage of water vapour, how come you're
not predicting disastrous consequences?

What would be the disastrous consequences? Brickwork can happily
contain moisture as long as it is not allowed to freeze and cause
spalling. In all of this, nobody has considered the more serious
consequences of the mortar washing out of the joints. As long as there
is a barrier stopping the seepage, the mortar will not wash out.
Surface sealants and finishes cannot provide this.

Stuart Noble wrote:
wrote:
wrote:


Stuart, please see the trade lit below. I have used this sytem to water
proof a brickwork viaduct in London and 18 months later the arches are
still dry and let out to tennants without a problem.


snip explanation

Better than Stuart's approach, but dont you think the best bet is to
just let the building work correctly in the first place?


The great
majority of damp old buildings are damp because they have been modified
inappropriately, whether by accident or intent. Common causes of damp
are blocked underfloor vents, external cement render, cement pointing,
use of masonry paints and so on.

Some certainly are damp by design, but theyre are a very small minority
imho. The problem is simply the general lack of understanding how old
buildings handle damp, leading to suggestions like trying to waterproof
the wall, and explanations like 'the bricks are porous.'

Lack of maintenance is also a common issue, sometimes causing
penetrating damp from blocked gutters and downpipes, rusted through
downpipes, blocked drains etc.


NT


So I wonder which category this railway arch comes under.
If these products prevent the passage of water vapour, how come you're
not predicting disastrous consequences?

wrote:
What would be the disastrous consequences? Brickwork can happily
contain moisture as long as it is not allowed to freeze and cause
spalling. In all of this, nobody has considered the more serious
consequences of the mortar washing out of the joints. As long as there
is a barrier stopping the seepage, the mortar will not wash out.
Surface sealants and finishes cannot provide this.

Given that these products are supposedly able to prevent the passage of
vapour, and therefore render the building hermetically sealed, the
conservationist taliban view is that the moisture generated by human
activity inside (yuk!) will not be able to escape. All stuff and
nonsense because in reality nothing comes close to a total seal on masonry.

I suspect silicates would reduce the porosity, and may well be the best
solution for bare brickwork. I'd be interested to know whether the
bricks have changed visually in your railway arch. Were they cleaned
first? Any photos anywhere?

For those stuck with painted bricks or, worse still, painted render, a
surface coating is still the only option. In this case, solvent based
masonry paints are IME the only products worth considering.

IMO you do whatever you need to buildings to make them habitable. We
need healthy young families with a roof over their head. We're not
running an architectural museum here.

The arches were brushed clean and blasted with compressed air to remove
the finest particles. This is all the budget would allow for as jet
washing etc was too costly. However, we have research on the product
uses with differing preparation methods, and there is no difference in
Sofix performance between jet washing and brushing.

There has been a slight darkening of the brickwork, but it is
consistent throughout and does not look false. There is not surface
finish like a sheen or gloss. I will dig some photos out and attempt to
post them. Not too sure how to do that.

I still stand by my point that sealing the brick face is by far the
worst thing anyone can do to brickwork. I cannot understand anyone
specifying it for any work of significance.

Guy King wrote:
The message .com
from contains these words:

Lack of maintenance is also a common issue, sometimes causing
penetrating damp from blocked gutters and downpipes, rusted through
downpipes, blocked drains etc.

Or - like our old house in Hounslow - the environment was soggy. I once
lifted the downstairs floorboards for something and the soil beneath
wasn't just damp it was wringing wet. Glad we only rented it!

That isnt any big problem, and doesnt preclude a dry house.

NT

Stuart Noble wrote:
wrote:

What would be the disastrous consequences? Brickwork can happily
contain moisture as long as it is not allowed to freeze and cause
spalling. In all of this, nobody has considered the more serious
consequences of the mortar washing out of the joints. As long as there
is a barrier stopping the seepage, the mortar will not wash out.
Surface sealants and finishes cannot provide this.

Given that these products are supposedly able to prevent the passage of
vapour, and therefore render the building hermetically sealed, the
conservationist taliban view is that the moisture generated by human
activity inside (yuk!) will not be able to escape. All stuff and
nonsense because in reality nothing comes close to a total seal on masonry.

I suspect silicates would reduce the porosity, and may well be the best
solution for bare brickwork. I'd be interested to know whether the
bricks have changed visually in your railway arch. Were they cleaned
first? Any photos anywhere?

For those stuck with painted bricks or, worse still, painted render, a
surface coating is still the only option. In this case, solvent based
masonry paints are IME the only products worth considering.

IMO you do whatever you need to buildings to make them habitable. We
need healthy young families with a roof over their head. We're not
running an architectural museum here.

It always puzzles me that you persist it making no effort to understand
the subject.

NT

The message . com
from contains these words:

Or - like our old house in Hounslow - the environment was soggy. I once
lifted the downstairs floorboards for something and the soil beneath
wasn't just damp it was wringing wet. Glad we only rented it!

That isnt any big problem, and doesnt preclude a dry house.

Except it made the whole house feel damp and smell musty. I know it
could have been fixed - but since it wasn't ours and we weren't planning
on staying ICBA.

--
Skipweasel
Pay no attention to the man behind the curtain.

It always puzzles me that you persist it making no effort to understand
the subject.

I suspect you find anyone who disagrees with you puzzling.

Please tell us why you find the products under discussion preferable to
a surface coating, given that they allegedly act as a total seal against
vapour. I thought breathability (aka putting up with damp) was the
cornerstone of your theory.

wrote:
The arches were brushed clean and blasted with compressed air to remove
the finest particles. This is all the budget would allow for as jet
washing etc was too costly. However, we have research on the product
uses with differing preparation methods, and there is no difference in
Sofix performance between jet washing and brushing.

There has been a slight darkening of the brickwork, but it is
consistent throughout and does not look false. There is not surface
finish like a sheen or gloss. I will dig some photos out and attempt to
post them. Not too sure how to do that.

I still stand by my point that sealing the brick face is by far the
worst thing anyone can do to brickwork. I cannot understand anyone
specifying it for any work of significance.


I totally agree, but this is purely academic since surface coatings are
unable to form an effective film on masonry. They soak in instead.
The clear repellants marketed by Sovereign Chemicals and others are
based on siloxanes which, as I understand it, penetrate in much the same
way as silicates without forming a film of any kind. Whereas silicates
are basically tiny particles of sand, siloxanes are greasy/rubbery. Both
are said to move about in the masonry in response to water.
Yes the photos woud be interesting but I think I can visualise the "wet"
look you mention. I expect there's a way to put them on the web for free
so that anyone can view them without invitation. You could use the web
space from your ISP but all that ftp stuff is a bit of a pain.

If you are using Pavix you get a very clever product which is much more
than a simple seal. The material is a hygroscopic solution that applies
hydrophilic and hydrophobic actions. It seeks water and combines with
it to grow crystals that resist water. The crystals, which adhere
tightly to the concrete pores, grow and shrink according to the amount
of available moisture. Consequently, the impregnate provides
water-resistance and reduced vapour permeability according to the
prevailing conditions. As Pavix is an impregnate, it cannot be damaged
or broken like a traditional seal.

Yufix is similar to Pavix, that is they both stop water penetrating
into the face of the brickwork, but allow water to pass through to the
outside. As neatly summed up earlier as a Gortex jacket for brickwork.

Sofix works in a slightly different way and prevents water passing in
either direction.

In my ( and a growing number of infrastructure owners) opinion,
environmentally friendly and integral protection provided by such
products is preferable to the "off the shelf" product available at B&Q.
The protection and preservation of heritage assets is tightly
controlled by English heritage etc. They categorically refuse to allow
any heritage assets (such as war memorials, grave stones etc) to be
sealed with a silicon sealer. However, products with the attributes of
the above are acceptable following a period of proving. So far, the
largest project for Yufix is the preservation of Mt Rushmore (currently
ongoing). They will not be using Thomsons Water Sealer for work like
this. Just because it is new or innovative, don't be scared or
dismissive. Try to embrace progression.

Stuart Noble wrote:
martinbyrne56 wrote:
I still stand by my point that sealing the brick face is by far the
worst thing anyone can do to brickwork.

I totally agree, but this is purely academic since surface coatings are
unable to form an effective film on masonry. They soak in instead.

Repeated coatings form a film, though (cf. painting MDF, cut kitchen
chipboard worktops, etc).

wrote:
wrote:


Just because it is new or innovative, don't be scared or
dismissive. Try to embrace progression.


Its a question of being realistic Martin. Some new building materials
and methods have problems that only show up many years down the line.
Many miracle treatments have been and gone, causing one problem after
another, and failing to resolve the problem. Despite over a century of
progress in damp technology, the original Victorian method of handling
damp in old buildings has proven over time to still be the best,
despite the technology's considerable age.

Perhaps your new wonder chemical really is wonderful, but I cant help
but notice 2 things worth bearing in mind:

1. Almost none of the new wonder damp cures in the last century have
proved worth adopting, despite often looking good initially

2. Damp treatments dont resolve the cause of the damp, and if the cause
is resolved, there is no need for such treatments anyway. Their
fundamental flaw is that they just dont address the point in 90% of
damp cases.

Truth is its a hard life when youre in business with these kind of
products.


NT


I think maybe it's time you revealed what you think the cause of damp is
in 90% of cases.

wrote:
If you are using Pavix you get a very clever product which is much more
than a simple seal. The material is a hygroscopic solution that applies
hydrophilic and hydrophobic actions. It seeks water and combines with
it to grow crystals that resist water. The crystals, which adhere
tightly to the concrete pores, grow and shrink according to the amount
of available moisture. Consequently, the impregnate provides
water-resistance and reduced vapour permeability according to the
prevailing conditions. As Pavix is an impregnate, it cannot be damaged
or broken like a traditional seal.

Yufix is similar to Pavix, that is they both stop water penetrating
into the face of the brickwork, but allow water to pass through to the
outside. As neatly summed up earlier as a Gortex jacket for brickwork.

Sofix works in a slightly different way and prevents water passing in
either direction.

In my ( and a growing number of infrastructure owners) opinion,
environmentally friendly and integral protection provided by such
products is preferable to the "off the shelf" product available at B&Q.
The protection and preservation of heritage assets is tightly
controlled by English heritage etc. They categorically refuse to allow
any heritage assets (such as war memorials, grave stones etc) to be
sealed with a silicon sealer. However, products with the attributes of
the above are acceptable following a period of proving. So far, the
largest project for Yufix is the preservation of Mt Rushmore (currently
ongoing). They will not be using Thomsons Water Sealer for work like
this.


Just because it is new or innovative, don't be scared or
dismissive. Try to embrace progression.

It isn't just a question of Sofix/Yufix/Pavix vs Thomsons Waterseal.
Silicate and siloxane based products have been around for a while and,
to my knowledge, no water repellant has ever been based on silicon.
I'm sure your products work very well but the claims that they're new or
unique I would take with a pinch of salt. You're not the UK agent by any
chance?

Nobody would deny that we must treat the cause not the sympton. But if
your cause is damaged Victorian waterproofing which happens to be
integral to the structre (such as a bitumen lining to the top ring of
the arch barrel) then you are not in any position to reapply that
coating. What we must also consider is that in 99% of cases of damp
treatment, the client is going make decisions based on cost alone.
Performance is secondary as he knows he will get a product to treat the
symptom and he is unlikely to want the disruption or cost of treating
the cause.

Obviously if you are talking about Buckingham Palace then you will do a
pucker job, but for average Joe, he will want an effective quick win,
which can be monitored and managed over time. Cost will always force
the issue.

I wish I was the UK agent. That job has gone to either ASI Ltd and PCIS
Ltd. I am only telling you of my experience of Engineering Heritage
and my time as a civil maintenance engineer.

I shoujld have included this in my last post. Silane based products are
on the decline. It is too costly and dangerous to use. The PPE for
apllicators and protection to the public every time you open a jar of
the stuff means that clients such as Londonon Underground and the
Highways Agency have banned its use. In fact, the HA have re-written
their standards exclusivley for the use of Pavix.

Stuart Noble wrote:

I think maybe it's time you revealed what you think the cause of damp is
in 90% of cases.

I'm not sure where you're going to go with this yet, but usually the
condensation or penetrating damp (which comprise the great majority of
damp cases) are in most cases caused by

- exterior ground level above floor level
- blocked underfloor vents
- waterproof wall coatings, eg exterior paints, cement render, or
waterproofing products
- blocked gutters and downpipes
- rusted through downpipes
- inadequate ventilation and/or high water vapour output (eg drying
clothes indoors)

etc


NT

wrote:

Nobody would deny that we must treat the cause not the sympton. But if
your cause is damaged Victorian waterproofing which happens to be
integral to the structre (such as a bitumen lining to the top ring of
the arch barrel) then you are not in any position to reapply that
coating.

Hang on, how many damp VIctorian houses have that problem? In the great
majority of cases the causes a

- exterior ground level above floor level
- blocked underfloor vents
- waterproof wall coatings, eg exterior paints, cement render, or
waterproofing products
- blocked gutters and downpipes
- rusted through downpipes
- inadequate ventilation and/or high water vapour output (eg drying
clothes indoors)

And no applied chemical addresses any of those issues.


What we must also consider is that in 99% of cases of damp
treatment, the client is going make decisions based on cost alone.
Performance is secondary as he knows he will get a product to treat the
symptom and he is unlikely to want the disruption or cost of treating
the cause.

Au contraire, remedying the cause is almost always cheaper, and in most
cases far cheaper.

Also you talk about curing the symptoms but not the cause, but how is
that possible? A soaked wall will display the same symptoms regardless
of whether its chemically treated. It will be cold, and condense more
moisture, plaster and paper will spoil, mould will often grow, the
interior will be made damp, and in the worse cases the bricks will
slowly disintegrate due to freeze damage.


Obviously if you are talking about Buckingham Palace then you will do a
pucker job, but for average Joe, he will want an effective quick win,
which can be monitored and managed over time. Cost will always force
the issue.

Yes, and this makes the choice of fixing the cause a no brainer. Would
Joe Average rather scrape the soil away from the underfloor vents, or
pay 4 figures for some magical dampproofing system? (Which doesnt
address the problem) Even if 3 figures, whish is as low as dampproofing
could be done for, is not going to win over an hour with a spade.

Same for high ground levels.

Same for blocked gutters

In the case of rusted downpipes discharging onto a wall, no chemical is
going to prevent further damp and freeze damage.

In case of waterproof wall coatings, no applied checmical can make any
material difference.

In case of high interior RH, again checmical treatment can not make any
difference to the dew point, and the water vapoour's plans to condense
out.

It just doesnt add up. And this is why anyone in the business can
either tell the truth and go hungry, or mislead clients and make money.
And sure enough, thats normally what happens IRL.


Yes there are cases not covered by these points, but they are a very
small percentage. Those are primarily underground brick cellar walls
with no DPM. Even there, its hard to see how any chemical could solve
anything.


NT

In the great
majority of cases the causes a

- exterior ground level above floor level
- blocked underfloor vents
- waterproof wall coatings, eg exterior paints, cement render, or
waterproofing products
- blocked gutters and downpipes
- rusted through downpipes
- inadequate ventilation and/or high water vapour output (eg drying
clothes indoors)

Sounds like a quote from Womans Own circa 1930.

wrote:
I shoujld have included this in my last post. Silane based products are
on the decline. It is too costly and dangerous to use. The PPE for
apllicators and protection to the public every time you open a jar of
the stuff means that clients such as Londonon Underground and the
Highways Agency have banned its use. In fact, the HA have re-written
their standards exclusivley for the use of Pavix.


Plenty of water based siloxanes on the market.....