Damp Proof Damp

[TheVictorian]

Can you take a picture of the brickwork in the cellar directly underneath the fireplace?

 

[MisterFish]

Hi JohnD

can you see the chimney breast in the cellar, and does it seem dry?

No and yes. I suspect that the previous owners had "something" done with the cellar - it is a dry room. I do know that neigbours all regularly have trouble with flooding in their cellars, something we have never had. I am really unwilling to start smashing down walls down there to solve this.

If you draw a pencil line round the wet patch, and pencil the date on it, you wil be able to see if/how fast it is drying out.

... Or I could just use the daily salt line to see the millimetre by millimetre track of that.

The metal bead (unless you use stainless, which is better) is galvanised, so in the absence of salt it should not go rusty that fast, especially indoors.

My thoughts exactly.

Incidentally, when you are lucky enough to have a cellar, you can often cut a ventilation hole into the flue from there, so it does not show in the room, and helps ventilate the cellar too.

Unless, as now seems may be the case, the cellar walls are the only thing stopping the cellar from flooding in which case it won't. The cellar is ventilated via ducting to the airbricks on the front of the house.

M

 

[MisterFish]

Can you take a picture of the brickwork in the cellar directly underneath the fireplace?

Not remotely easily, no. The floorboards are the original victorian ones. They are T&Ged with metal strips. Taking up floorboards without much destruction then becomes a nightmare. I know I just did some.

What I can tell you is that eight inches below the floorboards, (two inches below the floor joists), is the ceiling of the callar. So even with boards up the view is going to be VERY restricted.

 

[Micilin]

As John D says the bead should not rust. I have some old galv beads in a rack outside that are years old and have not rusted.

Good luck with details and hope to get up date soon

 

[MisterFish]

Good luck with details and hope to get up date soon

Soon as I get it, you will.

Thanks guys

 

[TheVictorian]

I suspect the cellar has been tanked or similar so the water come up wthout being visible below.

 

[dann09]

This post is essentially a Damp issue and would be better answered in the Building Forum. But, for the record:

As regards the render issue:
is it, indeed, render and a remedial skim?
Render is floated on and left a min. 24 hrs, and then skimmed - it's not a morning's work.
Plastic angle bead is often used for remedial work.

If the OP wishes to continue, then there are quite a few further Q's that he might be interested in answering?

 

[joe-90]

It's an answer he wants - not endless questions and NO answer.

 

[Micilin]

This post is essentially a Damp issue and would be better answered in the Building Forum. But, for the record:

As regards the render issue:
is it, indeed, render and a remedial skim?
Render is floated on and left a min. 24 hrs, and then skimmed - it's not a morning's work.
Plastic angle bead is often used for remedial work.

If the OP wishes to continue, then there are quite a few further Q's that he might be interested in answering?

I'd have thought a this was the place for a plastering query!

With certain additives you can skim over sand and cement on the same day, without the crazing etc that this would normally mean skimming on green render. That is standard practice ( if the render is set enough) An area that size can be done in a morning and the charge is okay.

But it does not look a good job due to the rusting. A plastic bead would not rust but the problem is not with the thin coat bead used, it is with the render (and the attitude of the renderer). The rust is merely a symptom.

When we know the composition of the render then we can go further, and the OP has to wait for that.

 

[NickB_99]

the two layers (and the injection) can be seen here.

In terms of spec that I got, the one I gave in my previous post was it. i.e. :

1. Remove plaster from the lower part of chimney breast
2. Inject DPC
3. Replace plaster with waterproofing formula.

Incidentally I had two quotes and, spec wise, that is pretty much what they both said. I assumed that was normal.

Additive used? - no clue, will ask when he gets back to me.

P.S. He just called me: The additive was "a salt nutraliser", he can't remember what it is called. He also says that the salt line is just what happens when new and old plasters meet, the rust is nothing and will wipe away when the thing dries, and that the job will dry happily in the next few days.

Looking at the picture, I can't see sign of much render underneath, the coat looks thin. It looks mostly an undercoat gypsum plaster under the multi-finish - especially on the corners under where the thin coat beads are bedded in.
OP - not expecting a reply from you on this - just waiting to see with all about what he says about point 3. I am hoping you get a satisfactory conclusion and the work put right.

 

[MisterFish]

Update.

We have a reply to the earlier question but I don’t think it gives us the answers we need. More of that in a moment.

It has now been over a week and the plaster still hasn’t dried very much at all, this was how it looked this morning.

The salt lines and tide marks around the edges of the work and beyond are now very pronounced, with fresh damage to the existing paintwork and noticeable crystalline salt outcrops in places. The rust bloom around the replacement beads is now very noticeable and there now appears to be the beginnings of a certain amount of pitting of the plaster surface itself, presumably again caused by salt crystallisation.

His reply came in by email last night. The relevant (to here) bit of that email said:

The materials used were a cement waterproofing additive to coat facing brick and seal all penetrating damp, from there we have applied a waterproofing flexible plastering agent, finished with a skim,

other products used

Damp cure
Pva

I will be getting back to him by email later today and thought I would let you guys see this first.

Any thoughts?

M

 

[Micilin]

Sounds like waffle and PVA is not to be used in damp conditions. Will look for a link.


He needs to give you the name of the products and the cert or origin for the sand.

 

[Micilin]

Spec sheet here on quick Google

http://www.trademate.co.uk/ProductExtra/HEN0002/04410292.PDF

Surfaces need to be dry, and PVA is biodegradeable in water. To clean it up, you use water

So not much cop in sealing water/damp or used in damp conditions .

What is the ' cement waterproofing additive' ?

It patently has not managed to 'seal all penetrating damp'


and if you have applied the additive above , why the need to

'from there we have applied a waterproofing flexible plastering agent'

(which also needs to be named)

And if those are effective , why use PVA?


'finished with a skim '

This man has never written a spec before and probably not read one properly other wise he could have made a better job of it.

Get back to him for specifics

Name every product, find out about the sand (again don' t lead him, ask him where it came from and what type it was.

INFO NEEDED

Products (Proprietary brand names not generic fudge like 'waterproofer' etc Even the PVA brand )
What was applied ?
Method?
In what order?
How were beads fixed?
How as surface prepared

 

[MisterFish]

Micilin

I have PMed you with reference to the above.

 

[MisterFish]

New update.

The John Wayne lookalike that did the job has been sacked. I then removed his plaster and took off more to a hight of 1 m. There I found that he had used a "mortar bed injection product" into the brick and had used about 2mm of cement render under the plaster. Yee-Haw!

I also raked out the bottom mortar joint and repointed with cement mortar. I allowed that to dry for a week and then about a fortnight ago I injected dampcure deeply into the chimney breasts.

It is now getting on for a month since I took off the plaster.

Throuout this time I have measured the moisture levels in the wall with a good quality moisture meter. This morning I measured the moisture level again and it had actually risen quite sharply. We have had a fair bit of rain, but I stress again that are no obvious ingress points for penetrating damp.

Is this normal?
What steps would folks here take now?
How long before I can get some render & plaster on the wall and get my room back?

Thoughts appreciated.