Rising Damp and failed Damp Proof Course

[stockhausen]

If there is damp and mould on the inside of an external wall (if you see what I mean), how can one show that it is due to a DPC failure rather than just condensation?

How does one (non-destructively) detect whether a DPC has failed?

 

[SeatIbiza]

What age is your property? Failure of a DPC is almost impossible unless it was defective to begin with...it is certainly something that wouldn't just occur one day.

Older properties would likely use slate as a DPC and that would just never fail, same goes with engineering bricks. Modern property is a membrane and, as above, would only fail due to a defect from the start. That being said, if it is older, it may not have one at all.

Are you sure it is linked to a failed DPC or has some "professional" told you that? I'd be looking at the property itself. Can you post a picture of the outside of where the problem is at ground level and a picture showing the whole including roof.

 

[fastwunz]

This smells of ‘I had damp proofing done but it hasn’t worked - who can I get compensation from?’ Lol

 

[fastwunz]

Also agree - DPC’s don’t inherently fail.

Could be bridging

 

[fastwunz]

What age is your property? Failure of a DPC is almost impossible unless it was defective to begin with...it is certainly something that wouldn't just occur one day.

Older properties would likely use slate as a DPC and that would just never fail, same goes with engineering bricks. Modern property is a membrane and, as above, would only fail due to a defect from the start. That being said, if it is older, it may not have one at all.

Are you sure it is linked to a failed DPC or has some "professional" told you that? I'd be looking at the property itself. Can you post a picture of the outside of where the problem is at ground level and a picture showing the whole including roof.

We also need to known floor construction - solid or suspended?

 

[Adam_151]

You could try looking at it the other way... rule condensation out first. Buy a Thermal hygrometer from the rainforest place and monitor it for a bit. Damp very rarely rises

 

[yak.h'cir]

I thought the whole rising damp thing was a myth pro-ported by certain companies to sell a product that ultimately does nothing.

https://www.heritage-house.org/damp-and-condensation/the-fraud-of-rising-damp.html
https://www.architectsjournal.co.uk...a-myth-says-former-rics-chief/5204095.article

The theory goes that if you've got a damp problem then it's not because water is being sucked up from ground level, but there will be another source that needs fixing - i.e. non breathable cladding has been applied outside? Leaking pipe? High humidity internally from drying clothes regularly inside, improper venting from cooking area/bathroom...

 

[stockhausen]

You could try looking at it the other way... rule condensation out first. Buy a Thermal hygrometer from the rainforest place and monitor it for a bit. Damp very rarely rises

I am certainly looking at significantly reducing condensation as a cause - I have already invested in a dehumidifier and a Bosch GlassVac. I would also utilise some digital hygrometers if the reviews weren't so "iffy".

I thought the whole rising damp thing was a myth pro-ported by certain companies to sell a product that ultimately does nothing.

The theory goes that if you've got a damp problem then it's not because water is being sucked up from ground level, but there will be another source that needs fixing - i.e. non breathable cladding has been applied outside? Leaking pipe? High humidity internally from drying clothes regularly inside, improper venting from cooking area/bathroom...

I don't think that the "whole rising damp thing" is a "myth" any more than I believe that climate change is a myth despite the reassurances of the POTUS. In this case there is a clear line of discolouration running up the inside of the outside walls to about 30cms above the floor. The Landlord's builder has stated (without any evidence) that the problem is 100% due to condensation.

Ventilation and drying laundry outdoors is tricky in a ground floor flat where there is no extractor fan in the kitchen, where the extractor fan in the bathroom doesn't "run on" when the light is switched off and doesn't include a humidistat, where the couple are out at work five days a week and in a country where it rains occasionally.

I accept that condensation is a real issue - I am trying to deal with it and not really looking for advice on that. What I am interested in is advice on identifying and proving the presence of rising damp and getting something done about it if it is a problem.

 

[RoyMi6]

I thought the whole rising damp thing was a myth pro-ported by certain companies to sell a product that ultimately does nothing.

https://www.heritage-house.org/damp-and-condensation/the-fraud-of-rising-damp.html
https://www.architectsjournal.co.uk...a-myth-says-former-rics-chief/5204095.article

The theory goes that if you've got a damp problem then it's not because water is being sucked up from ground level, but there will be another source that needs fixing - i.e. non breathable cladding has been applied outside? Leaking pipe? High humidity internally from drying clothes regularly inside, improper venting from cooking area/bathroom...

This is 100% how I feel.

100 year old house we bought had damp proofing done to stop rising damp - but everything was still mouldy in most rooms.

We moved in and I systematicly went round the entire house checking for broken pipes and blocked gutters and what do you know - literally EVERYTHING was cracked, broken or blocked.

Even a quick look could have identified half the problems but some company came in and charged for something that wasn't needed without doing any due diligence.

With everything fixed the mould pretty much got rid of itself in a week.

Honestly, dig out your drains and check that any source of water is moving away from the house before sending in those cowboys.

 

[SeatIbiza]

Yes - as I said, it will more likely be a latent defect in the property...

 

[Semple]

I assume this is your neices flat that you were talking about the other day?

I know you say she likes the flat/area, but you're really going to be fighting a losing battle. The landlord is going to do as little as he possibly can.

Life's too short, and health is too valuable, she'd honestly be better off finding another flat and not have to deal with the stress of all this.

 

[stockhausen]

I assume this is your neices flat that you were talking about the other day?

I know you say she likes the flat/area, but you're really going to be fighting a losing battle. The landlord is going to do as little as he possibly can.

Life's too short, and health is too valuable, she'd honestly be better off finding another flat and not have to deal with the stress of all this.

One year tenancy agreement with no break clause. As in the other thread, the Landlord is denying any responsibility and has supposedly brought in an unnamed "Expert" who says that there is no problem with rising damp or water penetration - I am not convinced but am not sure how exactly to prove the point - hence this thread.

I have given her a dehumidifier and she accepts that she will have to wait until the end of her tenancy agreement - one year older, wiser and more cynical.

 

[stockhausen]

Well, I have just visited my Niece's flat to deliver a MeacoDry ABC 12L Humidifier. As soon as I walked in I could smell the mould; hopefully the dehumidifier will help.

While there I noticed that at some point in time, someone has drilled some holes through the inner wall of a cavity wall in the bedroom and covered them with a grille. There are no matching holes and grille on the outside wall so that in effect the interior of the wall is connected to the cavity! I presume that this was an attempt to simulate an air brick for ventilation purposes (into the cavity).

Does anyone have any idea why on earth someone would do this? It seems absolutely insane to me.

 

[fastwunz]

Well, I have just visited my Niece's flat to deliver a MeacoDry ABC 12L Humidifier. As soon as I walked in I could smell the mould; hopefully the dehumidifier will help.

While there I noticed that at some point in time, someone has drilled some holes through the inner wall of a cavity wall in the bedroom and covered them with a grille. There are no matching holes and grille on the outside wall so that in effect the interior of the wall is connected to the cavity! I presume that this was an attempt to simulate an air brick for ventilation purposes (into the cavity).

Does anyone have any idea why on earth someone would do this? It seems absolutely insane to me.

Is it a chimney stack by some chance?

 

[stockhausen]

Is it a chimney stack by some chance?

No. it isn't. However, fair question.

 

[fastwunz]

No. it isn't. However, fair question.

Seems to be a somewhat miss guided attempt therefore to vent the cavity - seems fairly obvious that the landlord is and has been aware of the damp for some time - either them or the previous owners of course.

There is absolutely nothing to stop your niece getting in a damp guy herself - quotes are free.

Either that or just buy a protimeter (relatively cheap and good to have anyway) and test the walls herself. Send the evidence to the landlord

 

[stockhausen]

Seems to be a somewhat mis-guided attempt therefore to vent the cavity - seems fairly obvious that the landlord is and has been aware of the damp for some time - either them or the previous owners of course.

There is absolutely nothing to stop your niece getting in a damp guy herself - quotes are free.

Either that or just buy a protimeter (relatively cheap and good to have anyway) and test the walls herself. Send the evidence to the landlord

Protimeter, that's the name, I have been struggling to remember - thanks

Don't Protimeters depend on sticking pins in the wall (damaging it)? I suspect that the Landlord would kick up a fuss about that. There is one on Amazon for £160 which I could probably tolerate - there is also one for £18.50 but I wonder how accurate / reliable that is.

As to getting in someone to test for moisture, I suspect that they wouldn't be particularly interested unless they were invited in by the Landlord and he is highly unlikely to want that since as you suggest, he is likely to have known about the problem(s) for a while.

I suspect that he accepts a regular turnover of tenants and he relies on retaining some or all of the deposit, gets the tenants to clean the flat thoroughly on departure and occasionally gets the flat repainted to hide traces of mould and damp.

Some (not all) Landlords are absolute crooks.

 

[fastwunz]

Protimeter, that's the name, I have been struggling to remember - thanks

Don't Protimeters depend on sticking pins in the wall (damaging it)? I suspect that the Landlord would kick up a fuss about that. There is one on Amazon for £160 which I could probably tolerate - there is also one for £18.50 but I wonder how accurate / reliable that is.

As to getting in someone to test for moisture, I suspect that they wouldn't be particularly interested unless they were invited in by the Landlord and he is highly unlikely to want that since as you suggest, he is likely to have known about the problem(s) for a while.

I suspect that he accepts a regular turnover of tenants and he relies on retaining some or all of the deposit, gets the tenants to clean the flat thoroughly on departure and occasionally gets the flat repainted to hide traces of mould and damp.

Some (not all) Landlords are absolute crooks.

I’m a building surveyor and use one daily. Have done for years. The pins make a hole around 1mm so....... they are almost totally invisible.

They measure electrical resistance - you do not need to spend a fortune but similarly don’t get the cheapest lol

I have the ‘protimeter mini’ for reference

If it goes red then that is an indication of a problem - it is not a diagnosis of the issue or a measure necessarily of how wet an area is (it’s a good indication of how severe it is though).

Generally basements are always a bit damp unless they are tanked and vented properly - something which is costly and time consuming to achieve - hence the number of dodgy basement conversions.

It’s important to know the wall construction, floor construction, location/existence of DPC and the type, height of external ground levels etc - that’s before you start looking at other issues such as water tables and drainage

But then again, she is renting and at six months can likely exercise her break clause and get there smeg out of there - she may want to nudge prospective tenants though during the agents inevitable viewing window to let them know quietly about the damp hee hee

 

[stockhausen]

Many thanks for that, good advice based on practical, every day experience - thanks.

Quite by chance I remembered yesterday that someone I used to know a few years ago is a long time Environmental Health Officer. I will get in touch with him and ask for his advice.

My Niece is doing all she reasonably can to minimise the impact of condensation but the flat reeks of mould and I do believe that the Landlord knows of the problem and is simply shirking his responsibility until the tenant is entitled to move out when he will argue over the return of the deposit and get in another couple of unfortunates - again for just a year.

 

[Deleted member 651465]

Mould is harmful to the respiratory system but not in itself a massive concern.

I’d be worried if the mould is growing in areas that it can be disturbed and become airborne.

Shoot me an email if you’re concerned. I’m a chartered environmental H&S manager and could probably give you some advice.