Damp one side of wall

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Hi,

I have a room where all of the walls that have been dot and dab plaster boarded, are damp at the bottom. The other side of one wall is dry to the touch.

If you look at the photos, by the spade at the bottom, shows a damp brick below the damp coarse.

Any ideas?

Camerart.
 
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Possible condensate issues where the dot and dab has allowed cold bridging t the base of the boarding, producing condensate and eventually the black spot mould growth, not a good idea for the boards to be sat on tiles either, any condensate will be absorbed by the base of the gypsum boards. Damp brick below Dpc level shows Dpc is doing it's job.
 
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Possible condensate issues where the dot and dab has allowed cold bridging t the base of the boarding, producing condensate and eventually the black spot mould growth, not a good idea for the boards to be sat on tiles either, any condensate will be absorbed by the base of the gypsum boards. Damp brick below Dpc level shows Dpc is doing it's job.

Hi Dave,

That sounds right, I'll remove all of the black plasterboard, and re-do it.

Thanks,

Camerart.
 
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The ole' mind isn't as nimble as it used to be!

I remembered this morning that the floor level on the tile side is two bricks higher than the exposed side, making a bridge across the damp course. How do I get round this? The floor level must have been lifted up in line with the kitchen floor, many years ago.

Camerart.
 
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The level of the room behind the wall has been lifted to the level at the bottom chalk mark in the photo, with quarry tiles at the top mark.

1/ In the new wall in the gap, where do I put the damp course?

2/ Is it best to make the floor at the same level as the top of the tiles, or the top of the concrete, leaving it 1/2 inch low?

2/ Do I need to inject the bricks with damp course liquid? If so which level of bricks.

Camerart.

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ree

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Your inner floor is bridging the (slate?) DPC in the solid wall - unless there is a membrane below the inner floor? The DPC can clearly be seen in the bed below the chalk marks.

When you have removed the damaged plaster board look for a membrane, and why not post pics of the wall behind?

1/ what new wall? Why not scan a sketch of the proposed floor plan?

2/ your inner floor finished level will depend on the FFL's of the connecting floor(s).

3/ do not inject the bricks with anything.

However, if you wish, check out the Dryzone method to be injected inside and outside at the level of the first course of brickwork above the inner floor.
 
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I don't think there is a mambrane in the higher room. I won't be removing the plasterboard for some time, after I've finished this room.

I think the Dryzone or similar solution is what's needed.

I think you answered most of my questions, thanks

C.

 

ree

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On the face of it, for the new bit of wall you should lay a strip of DPC material at the top chalk mark height. Always try and keep all DPC's at the same level irrespective of what walls they are in.

However, looking at your previous post pics i can't put two and two together. The recent pics and the previous pics dont seem to match up?
 
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The photos in my first post, are at both sides of the wall, approximately where the new opening will be. Just to illustrate the damp on one side of the wall. Hope that clears things for up for you.
 

ree

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Sorry, i didn't make myself clear - by previous i meant from earlier dated post pics in your posting archive.

As regards the correct level for inserting a strip of DPC material simply do it level with the bed of the injected brick course.

It might be in your interest to remove the affected dot and dab plaster board now, to inject the dryzone at the correct level - and so that you have an idea about any membrane in the quarry tiled floor, and the state of the wall brickwork.

FWIW:
Using second hand bricks, tooth in the new panel of brickwork on the outside face.
If you need any advice on laying a new floor base come back here.
 
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The 'last years' photos are from the other end of the house (front) The plaster has just dried out, so now Ill monitor it. If you are interested in that thread please reply to it, to save complication:) http://www.diynot.com/forums/building/damp-wall.389106/page-2

I can't work on the quarry tiled side yet, but I'll strip that wall and inject it before finishing this toilet. so it will be as you say chronologically.

Would you finish the level at the bottom of the tile level or the top? It is quite unlikely that the tiles will be removed.

C.
 

ree

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When you say "finish the level ... etc." do you mean where is the new strip of DPC to be placed?

The reference to a "toilet", do you mean that old WC compartment or are you intending to install a new WC?

The pics of "toilet" in your archived pics show what where on the diagram you posted?
 
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When you say "finish the level ... etc." do you mean where is the new strip of DPC to be placed?

The reference to a "toilet", do you mean that old WC compartment or are you intending to install a new WC?

The pics of "toilet" in your archived pics show what where on the diagram you posted?

I have two posts, one regarding the fitting of a toilet and one regarding damp, in the same room. I kept them separate for simplicity.

I've answered my own question: I am going to build up the level of concrete in the new toilet room, where the level is low, up to the level at the top of the tiles in the higher level room.

Thanks for all of the answers, hopefully there won't be any more?

C.
 
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Hi,
18 months later, I've got the builder and plasterer in.

At one end of the floor tiles room, I've stripped the plasterboard off and the wall feels dryish to the touch with powder.

Here are some photos of the other end of the room. Toilet side shows a dry wall, while the kitchen side looks damp. [The toilet in the photo is not fixed;)]

A previous suggestion was that the damp is from condensation because the plasterboard was touching the tiles, a week ago I cut the bottom of the plasterboard. You can see a computer fan that has been blowing for a couple of days and there is a gap where the plasterboard isn't touching the wall, but it is not drying out. How long would it take?
C.
 

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I thought you said that you've "stripped the plaster board out"?

Whats "not drying out" - the p/board (or the wall)?

Anyway, if I understand whats going on then you should strip all of the stained plasterboard - all of it.

Your problems are not your p/board but the underlying cause(s) of any condensation, rising or penetrating damp.
 

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