Help with damp walls

InhaleMood

I hope people can give me some advice.
We bought a house a couple of years ago there was quite a rush to move in. We got a lot of walls reskimmed. The previous owner had a DPC done on the external walls.
1) We struggled quite a lot with damp on the chimney breasts, but since capping the chimney and putting a vent in, it has resolved downstairs. There is still some patches on the upstairs chimney breast wall. We have the dehumidifier going. They weren't getting better or worse.
Do I leave it longer and hope that it dries out?
2) There is an external wall that was fine until the last couple of days of heavy rain and now the whole bottom metre is damp. It is one of the walls that had the DPC. It is still under guarantee so I have the guy coming to look on Saturday. Do I ask him to redo it? We've recently decorated and put new skirting on, but the damp is the bigger issue
3) There is an internal wall that has low level damp, up to about 40-50cm. It has a radiator on it, the pipes are all external. The height doesn't rise, but it gets darker/damper. There are floorboards underneath. I have no idea what to do on this one.

After looking through the forum, I've seen a lot of comments suggesting that DPC is a con. If that is the case, what do I do?
Any advice would be really appreciated!

EssexHebridean

When you bought the property, what did the survey have to say about the damp problems - did it give any input into the possible causes? 

InhaleMood

Basically they said to contact the original DPC contractor:
"Damp meter reading were taken at 

various intervals throughout the ground floor accommodation and a number of elevated meter readings were found and we recommend 

that the original contractor for the previously mentioned chemical injection damp-proofing courses is invited back to comment upon the elevated meter readings and undertake the necessary remedial works."

FreeBear

How old is the property ?

Has the outside been rendered or painted with something like Sandtex ?

What are the ground levels like in relation to any air bricks and door thresholds ?

InhaleMood

FreeBear said:

How old is the property ?

Has the outside been rendered or painted with something like Sandtex ?

What are the ground levels like in relation to any air bricks and door thresholds ?

It's 1900 I believe. 
No refer on any of the outside walls. 
No air bricks. Nothing is particularly straight in this house, as a result, all of the internal doors are have a decent sized gap underneath them! External doors (front door and side door) don't have any ventilation. 

I hope I've answered those properly!

FreeBear

InhaleMood said:

FreeBear said:

How old is the property ?

Has the outside been rendered or painted with something like Sandtex ?

What are the ground levels like in relation to any air bricks and door thresholds ?

It's 1900 I believe. 
No render on any of the outside walls. 
No air bricks. Nothing is particularly straight in this house, as a result, all of the internal doors are have a decent sized gap underneath them! External doors (front door and side door) don't have any ventilation.

Oh dear. I was afraid you were going to say a turn of the century property. Chemical DPC and waterproof render/plaster is totally inappropriate for any building with solid brick walls. These damp proofing companies love that type of construction because they can go back every 10 years or so to sell yet more expensive "cures" whilst wriggling out of their colander grade guarantees.

A 1900 property may well have a slate, lead, or engineering brick DPC (possibly even a bitumastic one). Usually just under the door threshold, or a course or two below. Check the ground levels outside, and if too high, dig down a bit. That will go a long way in reducing damp in the walls. Also check your gutters, downpipes, and any lead flashing. If any of these are leaking, the walls will get damp.

If you pop over to the Period Property forum, you'll find loads of helpful people that can offer advice on managing damp based on real world experience. You might even find a familiar face or two

InhaleMood

FreeBear said:

InhaleMood said:

FreeBear said:

How old is the property ?

Has the outside been rendered or painted with something like Sandtex ?

What are the ground levels like in relation to any air bricks and door thresholds ?

It's 1900 I believe. 
No render on any of the outside walls. 
No air bricks. Nothing is particularly straight in this house, as a result, all of the internal doors are have a decent sized gap underneath them! External doors (front door and side door) don't have any ventilation.

Oh dear. I was afraid you were going to say a turn of the century property. Chemical DPC and waterproof render/plaster is totally inappropriate for any building with solid brick walls. These damp proofing companies love that type of construction because they can go back every 10 years or so to sell yet more expensive "cures" whilst wriggling out of their colander grade guarantees.

A 1900 property may well have a slate, lead, or engineering brick DPC (possibly even a bitumastic one). Usually just under the door threshold, or a course or two below. Check the ground levels outside, and if too high, dig down a bit. That will go a long way in reducing damp in the walls. Also check your gutters, downpipes, and any lead flashing. If any of these are leaking, the walls will get damp.

If you pop over to the Period Property forum, you'll find loads of helpful people that can offer advice on managing damp based on real world experience. You might even find a familiar face or two

Thank you. 
When you say to dig down a bit, I presume that is into the concrete. It seems quite a big job! 
I understand your thoughts regarding DPC, however the issue I have is that the quote for line plastering was £700 for an area about 1m x 0.5m.
Is that about right?!

FreeBear

InhaleMood said:

FreeBear said:

InhaleMood said:

FreeBear said:

How old is the property ?

Has the outside been rendered or painted with something like Sandtex ?

What are the ground levels like in relation to any air bricks and door thresholds ?

It's 1900 I believe. 
No render on any of the outside walls. 
No air bricks. Nothing is particularly straight in this house, as a result, all of the internal doors are have a decent sized gap underneath them! External doors (front door and side door) don't have any ventilation.

Oh dear. I was afraid you were going to say a turn of the century property. Chemical DPC and waterproof render/plaster is totally inappropriate for any building with solid brick walls. These damp proofing companies love that type of construction because they can go back every 10 years or so to sell yet more expensive "cures" whilst wriggling out of their colander grade guarantees.

A 1900 property may well have a slate, lead, or engineering brick DPC (possibly even a bitumastic one). Usually just under the door threshold, or a course or two below. Check the ground levels outside, and if too high, dig down a bit. That will go a long way in reducing damp in the walls. Also check your gutters, downpipes, and any lead flashing. If any of these are leaking, the walls will get damp.

If you pop over to the Period Property forum, you'll find loads of helpful people that can offer advice on managing damp based on real world experience. You might even find a familiar face or two

Thank you. 
When you say to dig down a bit, I presume that is into the concrete. It seems quite a big job! 
I understand your thoughts regarding DPC, however the issue I have is that the quote for line plastering was £700 for an area about 1m x 0.5m.
Is that about right?!

A photo of the wall would help - The wider the shot, the more context we have to make suggestions.

Lime plastering is a niche trade that can command a high price. To do it properly takes a lot more time & effort than using modern gypsum plasters. However, it is one of those skills that isn't particularly difficult to pick up. And lime plasters are much more forgiving than stuff like Multifinish.