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Hi all, I am an unwilling renovator! I have an issue with my German style house, comprising of proton blocks, Lime plaster with a porothon ceiling topped with a slab of concrete. One of my issues is that the concrete ceiling appears to be  causing a crack in mainly the gable end walls.  My first question is - does a inside first floor concrete slab need to have expansion joints in it? The size of the slab ie 14 m x 8 m.  Also it appears that the Lime render applied was not suitable for the driving rain in Donegal and that I may have to replaster some sections of the house.  I would love some expert advice before I ask local builders who will be unfamiliar with my building materials. Thanks so much for looking here 

31739247_1822020714503096_1110814508525289472_n(1).jpg

Edited by Catherine Weitbrecht
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Welcome. Your house is Definitely not built from mica blocks???

Render will be easy enough fixed. Old plaster giving issues will be removed and new plaster with waterproof additives can be used to seal it.

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Hi Catherine and welcome. 

 

Can you post some photos please, internally and externally, wide angle showing the roof and close details of the cracking too.

 

Do you have any photos of the house under construction?

 

Unfortunately some continental building methods have been applied in Ireland without due regard for the massive volume of rain we get and it has caused issues but there's plenty of knowledge on here to help.  

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Here are some photos and more info on my problem,

About 10 years ago we decided to wrap the house in Evertex as a means of protection against moisture. But now the vertex is peeling away in spots and it is a bit of a shock to see the state of the render underneath. 

 

https://beodom.com/en/news/entries/making-of-amadeos-first-floor-slab-with-precast-beams-and-ceiling-bricks.html  This link gives a good detailed overview of the structure of my ceiling. I am unsure how or if they did the thermal insulation on the outside of the slab. 20240201_132826.thumb.jpg.7dbab8b1ae46e8d85f44d65968841a46.jpg20230605_164332.thumb.jpg.a24eb12425da6008d5c164a3c663f4c2.jpg20230605_164332.thumb.jpg.a24eb12425da6008d5c164a3c663f4c2.jpg

20230605_164431.jpg

20240201_132753.jpg

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On 28/01/2024 at 21:53, Declan52 said:

Welcome. Your house is Definitely not built from mica blocks???

Render will be easy enough fixed. Old plaster giving issues will be removed and new plaster with waterproof additives can be used to seal it.

Definitley not Mica ... at least I dont have that problem. Its protherm blocks. Thank you for your reply 

 

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On 29/01/2024 at 14:43, ToughButterCup said:

Bitte viele Fotos.......

Willkommen

image.png

Thanks so much, I have attached some photos here, danke! 

On 29/01/2024 at 14:27, Iceverge said:

Hi Catherine and welcome. 

 

Can you post some photos please, internally and externally, wide angle showing the roof and close details of the cracking too.

 

Do you have any photos of the house under construction?

 

Unfortunately some continental building methods have been applied in Ireland without due regard for the massive volume of rain we get and it has caused issues but there's plenty of knowledge on here to help.  

Thanks very much for your post, I have attached some photos above under my description and also a link showing the ceiling construction. I think my main problem could be

the expansion of the ceiling slab/ and the lack of adequate insulation outside the slab ...  

 

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The evertex coating you used has popped up on lots of forums with issues regarding bubbling and peeling etc. They must have had some issues with previous jobs because they closed and reopened under the name https://everflexcoatings.ie

 

As far as I can tell it's a very thick paint, probably of very low permeability. 

 

When airborne vapour escaped from the interior of the house via air leaks it got to a point in the wall where the temperature fell below the dew point, the vapour condensed to water and as it couldn't dry out it soaked into the original line render, diluting the adhesives of the lime and it fell off as you can see. 

 

My theory is that insufficient air sealing was done below and above the first floor slab. There was an easy path for indoor air of high humidity to pass right through to hit the back of the render. Here it cooled and condensed into water. As the original lime was of high permeability, the condensed water was ultimately able to dry though it to the outside so damage was limited. 

 

However when the Evertex was applied the water couldn't go anywhere, it soaked into the lime render and then you had problems, gravity did it's part and the water migrated down the wall destroying the render below the slab area too. 

 

The almost perfectly straight fault lines in the render are my evidence of air leaks combined with the impermeable paint being the issue. 

 

I would almost certainly rule out differential expansion of the slab and walls as they are similar materials, and the distinct two lines at slab level rather than a complete band point towards air leakage rather than a thermal issue. 

 

TLDR:

 

Bad air sealing above and below the slab allowed moist internal air condense behind the impermeable paint dissolving the lime render. 

 

 

 

 

 

 

 

 

Edited by Iceverge
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 What can you do......

 

Well good news is that the house won't fall down. 

 

You should  start to take note of internal humidity. It should be no higher than ~60% RH at ~20⁰ .Heating and ventilation is how to achieve this. Ideally mechanical ventilation of some sort.  This will prevent the issue getting worse. 

 

Ideally you would remove skirting boards and ceiling plasterboard and air seal around the first floor slab internally. Practically this is probably not possible unless it's limited to a very small area of the house. 

 

In any case you will need to sort the external render as now it's exposed to the Donegal rain it will degrade quickly. 

 

This will require removing the existing paint and render and reapplying something of a higher permeability like lime or silicone render. Even something like less permeable (but more permeable than Evertex) like sand and cement with it's very high tolerance to moisture would probably be ok if you were to control internal humidity. 

 

However these solutions would only work if any exterior paints were to be of high permeability in the future. A couple of coats of an exterior urethane based paint would undo all the work again, especially with lime render. ( Sand and cement may survive as it doesn't mind the damp so much) 

 

The most robust and permanent solution I can see is to apply a layer of external wall insulation (EWI).  In Irelands temperate climate, this would ensure that the vapour that escapes via the cracks above and below the slab would almost never reach a point in the wall below the dew point and condense.  Normally this is rendered with a silicone or acrylic render however in our climate of driving rain this would need to be done very carefully or you might be back where you started from. It's not encouraged in Norway any more for that reason.

 

https://www.mdpi.com/2075-5309/8/7/93

 

External cladding , metal wood or fiber cement over the EWI would be very robust. Come to think of it you could omit the EWI and just do this anyway but you wouldn't solve the problem of water condensing in your wall then.

 

 

TLDR. 

 

1. Control internal humidity with heating and mechanic ventilation. 

2. Apply EWI + Render with caution or

3. Apply an external rain screen with or without EWI. 

 

 

 

 

 

 

 

 

 

 

 

 

 

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17 hours ago, Iceverge said:

The evertex coating you used has popped up on lots of forums with issues regarding bubbling and peeling etc. They must have had some issues with previous jobs because they closed and reopened under the name https://everflexcoatings.ie

 

As far as I can tell it's a very thick paint, probably of very low permeability. 

 

When airborne vapour escaped from the interior of the house via air leaks it got to a point in the wall where the temperature fell below the dew point, the vapour condensed to water and as it couldn't dry out it soaked into the original line render, diluting the adhesives of the lime and it fell off as you can see. 

 

My theory is that insufficient air sealing was done below and above the first floor slab. There was an easy path for indoor air of high humidity to pass right through to hit the back of the render. Here it cooled and condensed into water. As the original lime was of high permeability, the condensed water was ultimately able to dry though it to the outside so damage was limited. 

 

However when the Evertex was applied the water couldn't go anywhere, it soaked into the lime render and then you had problems, gravity did it's part and the water migrated down the wall destroying the render below the slab area too. 

 

The almost perfectly straight fault lines in the render are my evidence of air leaks combined with the impermeable paint being the issue. 

 

I would almost certainly rule out differential expansion of the slab and walls as they are similar materials, and the distinct two lines at slab level rather than a complete band point towards air leakage rather than a thermal issue. 

 

TLDR:

 

Bad air sealing above and below the slab allowed moist internal air condense behind the impermeable paint dissolving the lime render. 

 

 

 

Thank you so much for your very considered and most interesting reply to my issue.  

As I am not so well versed in some of the terms you used may I ask a few questions to get some further clarity? 

 

 

17 hours ago, Iceverge said:

1 “When airborne vapour escaped from the interior of the house via air leaks it got to a point in the wall where the temperature fell below the dew point, the vapour condensed to water and as it couldn't dry out it soaked into the original line render, diluting the adhesives of the lime and it fell off as you can see. 

My question: Re the airborne vapour, if and when if condenses to water would it now follow gravity and move down inside the honeycomb poroton block?  

 

 

2. My theory is that insufficient air sealing was done below and above the first floor slab. There was an easy path for indoor air of high humidity to pass right through to hit the back of the render. Here it cooled and condensed into water. As the original lime was of high permeability, the condensed water was ultimately able to dry though it to the outside so damage was limited. 

My questions: What do you mean by air sealing? It is true that the kitchen is just inside this wall but above the slab is a bedroom with low humidity.

 

However when the Evertex was applied the water couldn't go anywhere, it soaked into the lime render and then you had problems, gravity did its part and the water migrated down the wall destroying the render below the slab area too. 

My question or rather my assumption was that it was the driving rain that made its way into the hairline crack and  then migrated down the wall?  

 

The almost perfectly straight fault lines in the render are my evidence of air leaks combined with the impermeable paint being the issue. 

 

I would almost certainly rule out differential expansion of the slab and walls as they are similar materials, and the distinct two lines at slab level rather than a complete band point towards air leakage rather than a thermal issue. 

My question: The slab is concrete and the main walls are poroton ie terracotta so they are not so similar?  I am not 100% sure what you mean by air leakage ie that the block on the outside of the slab is thinner that the blocks of the main walls?

Again thank you so much Catherine

 

 

 

 

 

 

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In answer to Iceleverage excellent post

 

What can you do......

 

Well good news is that the house won't fall down.  

My reply Yes!  And yes it could be worse at least it is not a mica construction.

 

“You should  start to take note of internal humidity. It should be no higher than ~60% RH at ~20⁰ .Heating and ventilation is how to achieve this. Ideally mechanical ventilation of some sort.  This will prevent the issue getting worse”. 

My reply Donegal is generally 80% humidity outside! I do my best to keep the kitchen as near to 60 as possible and the other rooms are well ventilated.

 

-“Ideally you would remove skirting boards and ceiling plasterboard and air seal around the first floor slab internally. Practically this is probably not possible unless it's limited to a very small area of the house.”

My reply: As it is a poroton build with corresponding ceiling I don’t think I have any plaster board  as far as my memory tells me it was skimmed and plastered with hardwall. I had a look behind the upstairs skirting and no sign of anything suspect?

 

-In any case you will need to sort the external render as now it's exposed to the Donegal rain it will degrade quickly. “

My reply.. Yes, I have done some research and it seems that Monogries E may be a suitable render. Both Aldi and Lidl use it on their exteriors  according to the supplier.  See specifications here https://irl.sika.com/dms/getdocument.get/952adf22-e903-4cc5-bdb5-68bfcbf653bc/parex-monogris-e.pdf      My worry is that if I re apply a better high quality render and suitable breathable paints like Graphenstone that I may end up with the same problem ie if hairline cracks appear again at the first floor level and I have water ingress which inturns makes the crack bigger and the same merry go round starts again.

 

-“This will require removing the existing paint and render and reapplying something of a higher permeability like lime or silicone render. Even something like less permeable (but more permeable than Evertex) like sand and cement with it's very high tolerance to moisture would probably be ok if you were to control internal humidity. “

My reply  

 Can I use normal sand and cement on a terracotta block?  I have not been able to find an adequate answer to this.

 

-“However these solutions would only work if any exterior paints were to be of high permeability in the future. A couple of coats of an exterior urethane based paint would undo all the work again, especially with lime render. ( Sand and cement may survive as it doesn't mind the damp so much) 

My reply I have sourced Keim paints and the lesser expensive Graphenstone paint which are used in restoring original historic Lime plaster.  

 

The most robust and permanent solution I can see is to apply a layer of external wall insulation (EWI).  In Irelands temperate climate, this would ensure that the vapour that escapes via the cracks above and below the slab would almost never reach a point in the wall below the dew point and condense.  Normally this is rendered with a silicone or acrylic render however in our climate of driving rain this would need to be done very carefully or you might be back where you started from. It's not encouraged in Norway any more for that reason.

My reply  Yes I am not too fond of this idea as if rain or moisture did find its way in I will be back to where I started.

 

https://www.mdpi.com/2075-5309/8/7/93

 

External cladding , metal wood or fiber cement over the EWI would be very robust. Come to think of it you could omit the EWI and just do this anyway but you wouldn't solve the problem of water condensing in your wall then.

My reply.  External cladding would be a good solution if the water was coming from outside

 

 

It is probably not possible to put into words how much I appreciate the time you have taken to reply and to share your possible solutions with me.

It can also be that I am omitting some information as I am so used to seeing it from my own eyes.

Yours most sincerely Catherine

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More questions arising from Iceleverage's post 

1 “When airborne vapour escaped from the interior of the house via air leaks it got to a point in the wall where the temperature fell below the dew point, the vapour condensed to water and as it couldn't dry out it soaked into the original line render, diluting the adhesives of the lime and it fell off as you can see. 

My question: Re the airborne vapour, if and when if condenses to water would it now follow gravity and move down inside the honeycomb poroton block?  

 

 

2. My theory is that insufficient air sealing was done below and above the first floor slab. There was an easy path for indoor air of high humidity to pass right through to hit the back of the render. Here it cooled and condensed into water. As the original lime was of high permeability, the condensed water was ultimately able to dry though it to the outside so damage was limited. 

My questions: What do you mean by air sealing? It is true that the kitchen is just inside this wall but above the slab is a bedroom with low humidity.

 

However when the Evertex was applied the water couldn't go anywhere, it soaked into the lime render and then you had problems, gravity did its part and the water migrated down the wall destroying the render below the slab area too. 

My question or rather my assumption was that it was the driving rain that made its way into the hairline crack and  then migrated down the wall?  

 

The almost perfectly straight fault lines in the render are my evidence of air leaks combined with the impermeable paint being the issue. 

 

I would almost certainly rule out differential expansion of the slab and walls as they are similar materials, and the distinct two lines at slab level rather than a complete band point towards air leakage rather than a thermal issue. 

My question: The slab is concrete and the main walls are poroton ie terracotta so they are not so similar?  I am not 100% sure what you mean by air leakage ie that the block on the outside of the slab is thinner that the blocks of the main walls?

Again thank you so much Catherine

 

 

 

 

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1 hour ago, Catherine Weitbrecht said:

Thank you so much for your very considered and most interesting reply to my issue.  

As I am not so well versed in some of the terms you used may I ask a few questions to get some further clarity? 

 

Sure.

 

1 hour ago, Catherine Weitbrecht said:

My question: Re the airborne vapour, if and when if condenses to water would it now follow gravity and move down inside the honeycomb poroton block?  

 

Vapour needs a surface to condense onto, like a bathroom mirror. If there was an unbroken airpath under and over the slab then it could have moved un hindered until it met the cold back side of the render. 

1 hour ago, Catherine Weitbrecht said:

What do you mean by air sealing? It is true that the kitchen is just inside this wall but above the slab is a bedroom with low humidity.

 

Normally done to join two parts of a house together to prevent air leaks at the interface. It's best done with some permanently elastic material like airtightness tape or paint to accommodate any movement. Walls to floors. walls to ceilings, walls to windows etc. the idea is to create a completely airtight seal.

 

IMG_0692.thumb.jpeg.94f96171c892db1823fcce69fa0bf137.jpeg

 

Here is how I did our windows and floor. I filled all large gaps with sand and cement mortar and then painted on blue airtightness paint which dried to black. Tape was used to seal the OSB window boxes to the window frame. (For anyone who's interested we used a parge coat first near the floor and around the window to save using up too much expensive airtightness paint).

 

 

Have you any actual measurements of the bedroom relative humidity? Air tends to equalise pretty well in a house with open doors. You can pick up a cheap hygrometer for less than €10?

 

1 hour ago, Catherine Weitbrecht said:

My question or rather my assumption was that it was the driving rain that made its way into the hairline crack and  then migrated down the wall?  

 

I'm working on a best guess here. Do you have internal photos too? Was it ok before the Evertex? Has the wall been mechanically stressed regularly , for instance by a football?

 

1 hour ago, Catherine Weitbrecht said:

The slab is concrete and the main walls are poroton ie terracotta so they are not so similar?  I am not 100% sure what you mean by air leakage ie that the block on the outside of the slab is thinner that the blocks of the main walls?

Again thank you so much Catherine

 

 

 Over a 1m distance with 50° of temperature difference they will differentially expand by less than 0.3 mm. Assuming the interior of the house is at a relatively stable temperature then maybe the outer 50-100mm might be subject these variations over a year. In any case the differential movement would be 0.01-0.03mm. About the width of a hair, hardly significant. 

 

The air leakage is the vapour heavy air from inside making its way to the outside via air paths. 

 

IMG_0693.thumb.jpeg.7a49c70d28b4786c135606111d91d947.jpeg

 

1 hour ago, Catherine Weitbrecht said:

Donegal is generally 80% humidity outside! I do my best to keep the kitchen as near to 60 as possible and the other rooms are well ventilated.

 

Its the absolute humidity you need to think about although its hard to measure so the relative humidity is often used. Relative humidity is temperature dependant though so external air at 100%RH and say 10° actually has less moisture than internal air at 20° and 50%RH.

 

 

 

IMG_0694.png.fcda9ee20f4ef85119d6250c2420c734.png

 

Do you have a mechanical ventilation system?

 

1 hour ago, Catherine Weitbrecht said:

As it is a poroton build with corresponding ceiling I don’t think I have any plaster board  as far as my memory tells me it was skimmed and plastered with hardwall. I had a look behind the upstairs skirting and no sign of anything suspect?

 

Pictures please. in good light, close and wide shots. 

1 hour ago, Catherine Weitbrecht said:

Yes, I have done some research and it seems that Monogries E may be a suitable render. Both Aldi and Lidl use it on their exteriors  according to the supplier.  See specifications here https://irl.sika.com/dms/getdocument.get/952adf22-e903-4cc5-bdb5-68bfcbf653bc/parex-monogris-e.pdf      My worry is that if I re apply a better high quality render and suitable breathable paints like Graphenstone that I may end up with the same problem ie if hairline cracks appear again at the first floor level and I have water ingress which inturns makes the crack bigger and the same merry go round starts again.

 

Theres no point in finding any products until you really nail what caused the issue initially in my view. 

 

1 hour ago, Catherine Weitbrecht said:

Can I use normal sand and cement on a terracotta block?  I have not been able to find an adequate answer to this.

 

Yes if it is stripped back to the bare surface first. However you would still have moisture trapped behind it.

 

1 hour ago, Catherine Weitbrecht said:

have sourced Keim paints and the lesser expensive Graphenstone paint which are used in restoring original historic Lime plaster.  

 

I would hold fire on any purchases for now.

 

1 hour ago, Catherine Weitbrecht said:

External cladding would be a good solution if the water was coming from outside

 

 

The moisture that caused the issue originated (i think) from inside. However when this damaged the render then the rain was able to damage it further. 

 

I think Ireland is just too wet to consider materials like lime render unless you are prepared to constantly maintain it.  

 

Thats why almost all houses here have sand and cement over a block rain screen. It's just so massively moisture tolerant. Its no different from a ventilated metal rainscreen, or timber or fiber cement. Although in a cavity wall it does contribute to the structure it's primary function is to keep the rain off the inner wall.

 

 

 

 

 

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Thank you very much for all the great information in your reply.

So to answer your questions-

I dont have a mechanical ventilation system

I moved the hygrometer around and to my surprise the bedrooms were higher than I thought ie at times almost 70%

The problem was not ok before Evertex. We were searching for a solution and thought Evertex might help, in hindsight we now know it was not. 

I have attached a few pictures to show how the problem started  appearing  ie in the first picture  a20240208_121742.thumb.jpg.d224cf516d4a06d8ae54313b5c05824e.jpgnd then how bad it actually is now. 20240208_124220.thumb.jpg.fa96cfa1c312fce2216bf0de77381d5f.jpg

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On 08/02/2024 at 13:06, Catherine Weitbrecht said:

Don't have a mechanical ventilation system

 

This is probably a cause and happily a part of the solution to your issue. 

 

Is there extractor fans fitted to your bathrooms? This might be an easyish fix. 

 

You'll need something that moves a gentle steam of fresh external air through the house all day.

 

As an aside this quirk of unventilated houses is only a problem of the past 50 years in all of human existence. Olden houses were constantly ventilated and heated by a fireplace that burnt from morning to night. 

 

 

On 08/02/2024 at 13:06, Catherine Weitbrecht said:

We were searching for a solution and thought Evertex might help, in hindsight we now know it was not. 

 

Almost everyone believes that moisture damage in a house comes from bulk water from the outside but in reality this is very little. It's understandable because a leak is easy to see with your eyes. I don't think it was a problem in your case. 

 

In reality most of the damage comes from internal moisture laden air condensing onto cold surfaces and then not being able to dry. 

 

Let's pick through those pics. They're really helpful. 

 

 

 

Screenshot_2024-02-10-17-19-17-522_com.android.chrome-edit.thumb.jpg.cedba67009bc2da62c3455fe559b19be.jpg

 

I think that a combination of high internal humidity (caused by low temps and low ventilation) combined with trapping of some construction moisture by material's of low permeability has created an issue that we see above

 

Can you remember the paint you used internally? I suspect it was "plastic" emulsion that combined with the smooth surfaces of the gypsum plaster sealed the wall. Unfortunately this trapped moisture inside (from construction and air leaks) and it leached up the wall to the ceiling. Where it started making it's way across the plasterboard. The resulting bubbles are because of the water dissolving compounds in the wall and expanding. 

 

 

 

IMG_20240210_172713.thumb.jpg.a0e984173607e77f61362729fc97ec37.jpg

 

 

 

This is a little more concerning in my view. The very localised area of dampness suggest a higher chance of external water getting in. Can you take photos of the outside of this wall and show me please. Specifically at and above the area of leaks and to both sides. 

 

 

 

 

 

 

 

In any case the advice remains the same. 

 

You need to grasp this by the "physics"

 

"Chemistry" from a tub or bottle won't fix the issue. 

 

DRY THE WALL by

 

1. Internally lower the humidity by (I) increasing temperature and (ii) increasing ventilation mechanically 

 

2. Prevent condensation happening in the wall by keeping it warm by (I) internal heating (ii) external insulation

 

3. Stop any rain ingress by (I) adding an external rain screen. (ii) overhangs help too.

 

 

 

 

 

On 08/02/2024 at 13:06, Catherine Weitbrecht said:

 

 

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Thank you so much again for all the information in your reply 

 

 

1. The paint used inside is plain emulsion  ie not satin or plastic finish. 

2. No extractor in the bathroom we just open the windows

3 I have 2 fireplaces which I use regularly in winter time .. not morning till night but a few hours each day 5 days a week approx 

4. The picture that you said was most worrying is how all the patches started. 

5. There is no plasterboard on the ceilings just plaster. 

6, Pictures below show the outside of the wall  The close-up show a crack in the Evertex which rain can come in. Above that was a previous crack in the Evertex which I filled with silicone 

7. As the proton blocks are probably more porous than cement blocks (?) I had imagined that the crack on the outside plaster regardless of the cause of the crack is now the main culprit of the water coming into the house?  

Many thanks Catherine 

20240213_100939.jpg

20240213_100851.jpg

20240213_100707.jpg

20240213_100758 (2).jpg adjusted .jpg

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23 hours ago, Catherine Weitbrecht said:

 

1. The paint used inside is plain emulsion  ie not satin or plastic finish. 

 

Probably still too vapour impermeable and lightly caused an issue. 

 

23 hours ago, Catherine Weitbrecht said:

2. No extractor in the bathroom we just open the windows

3 I have 2 fireplaces which I use regularly in winter time .. not morning till night but a few hours each day 5 days a week approx 

 

Insufficient in Ireland, the air is just too humid to absorb enough moisture to do without constant mechanical ventilation. 

 

If you can I would install a dMEV fan in all the wet rooms. 

 

Unity CV2 GIP (greenwood.co.uk)

 

These are quite good, low noise levels and if you keep an eye on ebay you can get one posted to Ireland for about €60. 

 

You'll need to core a hole in the wall which will require someone with the appropriate drill to be hired and a electrician to wire them up. 

 

23 hours ago, Catherine Weitbrecht said:

4. The picture that you said was most worrying is how all the patches started. 

 

It's impossible to say really without having a poke around, it could all have originated from outside. I'm making a best guess from the pictures. 

23 hours ago, Catherine Weitbrecht said:

7. As the proton blocks are probably more porous than cement blocks (?) I had imagined that the crack on the outside plaster regardless of the cause of the crack is now the main culprit of the water coming into the house?  

 

Not really, cement blocks are very porous. Just the cavity wall creates a very tough barrier for water to cross from outside. 

 

 

 

My advice remains the same. 

 

Mechanically ventilate and heat inside. 

Insulate outside. 

Add a rain screen with a cavity outside. 

 

 

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Thank you

 We have found old photos of the house before Evertex was applied. 

One interesting point is that on the outside the problems seem to be on top of the slab outside but on the inside it is under the slab. Is this of any help in diagnosing the problem?  Is it simply gravity taking in the water on the weak joint at the top of the slab and flowing down and into the weak joint underneath the slab? 

 

Could there be a solution that involves repairing the wall outside ie the  joint at the slab level on the gable wall?

One suggestion I got was to strip a 40 cm section across the gable at the joint level and repair the problem in this way, to do something to stop the cracking of the wall.  reinforce it in some way, mesh and lead were suggested.

Thank you

 

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1 hour ago, Catherine Weitbrecht said:

We have found old photos of the house before Evertex was applied

 

Post them please. 

 

1 hour ago, Catherine Weitbrecht said:

One suggestion I got was to strip a 40 cm section across the gable at the joint level and repair the problem in this way, to do something to stop the cracking of the wall.  reinforce it in some way, mesh and lead were suggested.

Thank you

 

 

Sounds like a bodge to be honest. You're lightly to need to revisit it unless you do it once and properly. 

 

 

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Am I right in understanding that this house in Donegal is built using Porotherm blocks, with no cavity, rendered externally and plastered internally?

 

If that is the case it is not surprising it has damp issues.

 

Porotherm is a real Emperor's New Clothes product.  Almost no "therm" at all to the stuff and very difficult to cut or fix to.  It does have quite high compressive strength and lower density due to the voids.

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Yes house in Donegal, the house is quite warm despite the damp issues.

 

Photos from pre Evertex time. 

 

First picture is the front of the house or south side

Second is the east or kitchen gable end 

Third is inside of the south side 

Fouth picture is the Kitchen gable end

DSC02620.thumb.jpg.4e27044eebfb96be71653042b3a25db8.jpg

DSC02628 - Copy.jpg

DSC02625 - Copy (2).jpg

DSC02630.jpg

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