Damp Internal Wall

Soldato
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Hi all,

I got a wall in my hallway that is suffering from damp troubles.

This is what it looks like inside and outside:






The paint is bubbling up, 2 years ago I got all of that external wall treated with an injection on the outside.
The internal wall has been re-plastered 2 years back. It all looked good for a while but the damp to re-appear.

The internal wall to my surprise when I got the property (6 years back) is actually plaster board, I did wonder why plaster board was used here, when the rest of the walls are brick/block.

Looks certain there is something I need to to do the outside of the wall but what can I do to stop/halt the internal damp coming through?
 
Soldato
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that is a brand new air brick
been there since the world cup - pretty sure inside was good and fairly clean.
 
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Is there any potential source for sub surface water nearby? No chance of a blocked drain or anything?

What material is below the bottom of the white painted bricks?

Injection treatment is a total con.
 
Soldato
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Is there any potential source for sub surface water nearby? No chance of a blocked drain or anything?

What material is below the bottom of the white painted bricks?

Injection treatment is a total con.

there is a gutter above but it is very far.

Looking at the first picture on the right hand side some of the cement is broken - I wonder if another layer of cement on top of the black paint bit will help.

the floor is concrete, it's a part of the house that wall never gets much sunshine so lots of algae on the floor etc.
 
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Need a bit more information. How old is the house? it will depend if the wall has a cavity on how you solve the issue.

What you did was waste your money on getting the wall injected with whatever you had it injected with. In my experience that only makes the problem worse by giving the wall more holes!. The paint on the outside of the building isn't allowing the water to escape the brick work. Rain will soak into the brick out but then can`t get out which is the issue you are having now. Bricks are like sponges and when it stops raining the wind will allow the water to evaporate out of the brick work.

You need to get that stuff cleaned off the outside of your house and allow the bricks to breathe. Do not use any form of acid wash either as you can damage the fired covering of the bricks will just add to your problems. You can only start to tackle the inside when you have sorted the outside. Which by the look of things will be removal of the damp plaster and reinstatement after.
 
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there was damp in other places but since the injection that doesn't occur
it's only on this small part where the issue is

it's a 1930's build almost 90-100 years old. I suspect that is a cavity wall as I could never work out why the inside wall is plasterboard.

what do I need to use to clean the outside of the bricks? I will prob do this in spring/summer but just looking for advice now

I got gut a feeling that the previous owners at some point took all of the internal bricks/blocks away and changed it to plaster board probably for the same reason as I'm putting this post up for.
 
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Associate
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I got gut a feeling that the previous owners at some point took all of the internal bricks/blocks away and changed it to plaster board probably for the same reason as I'm putting this post up for.
ummmm, then you really need to get that checked out. If that is a cavity wall then the internal wall is actual the wall that holds the loads of the house the external brick work is normally just the skin you really need to get that check out as you might currently be having issues with your house sinking in that area and yes if you have no block work or brick there then that will easily be what your issue is since the water is just soaking through the out brick skin into your house.

Regarding the outside of the house, try and bursh some of it off on the mortar for now as this will allow the water to escape from at least between the bricks. If you leave it like this eventually the bricks will start spalling.
 
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30’s may be either solid wall or cavity. The plasterboard will be dot and dab (boards stuck on with ‘adhesive) which will usually have a small void behind it. It definately wont just be one skin!

Check airbricks for flow and gutters for leaks. What is the room used for?
 
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Remove the paint as a first step and then look at removing the concrete. The concrete is a big slab right next to the wall stopping proper drainage. You want a french drain against the wall with sufficient shingle to allow any rainwater to rain down through the shingle into the submerged drain and away from the house. It also stops “splash back” so the wall generally stays drier.

You want a gap at least 3-5 inches from the brick wall and after that you can patio it as normal. Did this at a similar house I used to own and it completely cleared it. Also the concrete path is ugly!
 
Soldato
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ummmm, then you really need to get that checked out. If that is a cavity wall then the internal wall is actual the wall that holds the loads of the house the external brick work is normally just the skin you really need to get that check out as you might currently be having issues with your house sinking in that area and yes if you have no block work or brick there then that will easily be what your issue is since the water is just soaking through the out brick skin into your house.

Regarding the outside of the house, try and bursh some of it off on the mortar for now as this will allow the water to escape from at least between the bricks. If you leave it like this eventually the bricks will start spalling.


what am I brushing off of the wall and how do I know exactly where to do that?

30’s may be either solid wall or cavity. The plasterboard will be dot and dab (boards stuck on with ‘adhesive) which will usually have a small void behind it. It definately wont just be one skin!

Check airbricks for flow and gutters for leaks. What is the room used for?


It is in the hallway when entering the property, I can check the airbrick by poking something into it possibly but the gutters do need a clean but don't have a ladder to do it, one on the list.

Hallway can be hot and cold together, the front door is old and has condensation/mould on it, they are plans to change it in the future with a new porch. (no porch currently)

I know this is also a problem, but got to wait to build the pot up first.

On the left of the internal view there is a return, is there a window there or a door?

that is a little coupboard that houses the electric main box

I will look inside there but pretty sure it's generally okay under there.

Remove the paint as a first step and then look at removing the concrete. The concrete is a big slab right next to the wall stopping proper drainage. You want a french drain against the wall with sufficient shingle to allow any rainwater to rain down through the shingle into the submerged drain and away from the house. It also stops “splash back” so the wall generally stays drier.

You want a gap at least 3-5 inches from the brick wall and after that you can patio it as normal. Did this at a similar house I used to own and it completely cleared it. Also the concrete path is ugly!

Thanks I think this is a good suggestion but this is on a shared driveway. Where do I stand on making this change?

I don't believe I got a drain near by, there was one but it got concreted over a few years back as it was no longer required.
 
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Thanks I think this is a good suggestion but this is on a shared driveway. Where do I stand on making this change?

I don't believe I got a drain near by, there was one but it got concreted over a few years back as it was no longer required.

Ask the neighbour or look to cut a trench into the existing concrete so you have a channel against the wall for your drainage channel. There will be a drain you can connect to somewhere or otherwise to a soak away
 
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how deep will it need to be? - it is the side of the house - but not all of the house has this problem though.

You want to go down 1-2 foot to allow plenty of backfill or more if you can’t connect to a drain and it’s a soak away
 
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I would say that that wall is solid block. My house is around the same age and all external walls are would double thickness brick.

The half bricks that you see in the picture are the give away. They are rotated through 90 degrees to tie the two layers together.

The air brick at the bottom I'm going to assume you have a suspended floor on your ground level not a concrete slab. So that will be ventilating under the floor
 
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yes it is a suspended floor what difference does it make?

Just pointing out that the air brick isn't ventilating between layers of brick it's ventilating under the suspended floor.

I would assume the issue is as others have stated.

Lack of drainage up the wall and splashback onto the bricks with the painted finish is retaining moisture in the wall
 
Soldato
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Just pointing out that the air brick isn't ventilating between layers of brick it's ventilating under the suspended floor.

I would assume the issue is as others have stated.

Lack of drainage up the wall and splashback onto the bricks with the painted finish is retaining moisture in the wall

but why would it only be an issue on this part of the wall - the rest of the wall is okay

I will check the gutters + airbrick to see if it helps, then perhaps that pea shingle approach will be the best long term in this case.
 
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