DPC installed two owners ago

FreeBear

stuhse said:

It would appear the damp here is rising damp ?. The source will always be there- its the ground it cannot be removed.  In modern houses it is kept at bay by installing a horizontal damp proof course just above ground level during its construction and this has been common practice for many years.  However many many houses were built before the idea of a damproof course was compulsory  or in older houses if has failed as appears to be the case here.

A DPC could be one of many materials - Lead, slate, engineering brick, poured bitumastic, bitumastic felt, or (in modern buildings) a plastic. The use of a DPC started to become standard practice in the Victorian period.

Whilst a DPC may suffer from isolated failure (from cracks forming), it does not just fail along the entire length of a wall. Far more likely that a DPC is breached by the build up of ground levels (easy enough to fix in most cases), or the base of the wall is being soaked by water splashing up from hard paving. For the latter, fixing the source of the water (leaking gutter perhaps) and maybe installing a french drain will pay dividends.

Yes, rising damp does exist in some buildings, but it is a very rare phenomenon and no where near as common a problem as these damp proofing companies make out (why is it, they always specify treatment to 1-1.2m). I only know of one case, and that was due to a wall built with very soft brick sitting in a permanently waterlogged soil and no DPC. Rebuilding the wall after installing a proper DPC (none of these magic chemicals) was the right fix. No membranes or waterproof render/plaster required.

Emily_Joy

FreeBear said:

A DPC could be one of many materials - Lead, slate, engineering brick, poured bitumastic, bitumastic felt, or (in modern buildings) a plastic. The use of a DPC started to become standard practice in the Victorian period.

Whilst a DPC may suffer from isolated failure (from cracks forming), it does not just fail along the entire length of a wall. Far more likely that a DPC is breached by the build up of ground levels (easy enough to fix in most cases), or the base of the wall is being soaked by water splashing up from hard paving. For the latter, fixing the source of the water (leaking gutter perhaps) and maybe installing a french drain will pay dividends.

The house is built on an elevated position. But then there is a tiered garden and I can imagine the problem could be caused by ground levels. The question is what to do now: is it better just to sit still and wait for the problem to reappear or try to investigate further? 

(I think there is actually horizontal DPC, vertical DPC, and vertical tanking. In the "legend" in the bottom the work actually done is "highlighted" with a pencil).

stuart45

Is it face brickwork outside or rendered?

Emily_Joy

stuart45 said:

Is it face brickwork outside or rendered?

Outside is not rendered.

ThisIsWeird

Sit still. With drink in hand. Enjoy.
Chances are the problem has been resolved. 
There remains the possibility, I guess, that the house has been pre-sale redecorated in order to cover any issues, hence its current immaculate appearance. Does it look freshly done?
Can you find the previous sales partics on Zoopla?

Emily_Joy

ThisIsWeird said:

Sit still. With drink in hand. Enjoy.
Chances are the problem has been resolved. 
There remains the possibility, I guess, that the house has been pre-sale redecorated in order to cover any issues, hence its current immaculate appearance. Does it look freshly done?
Can you find the previous sales partics on Zoopla?

I can find the previous sales partics on zoopla. What am I looking for? The previous owner installed new windows a few years ago and turned a lovely front garden with roses into a car parking place ... the owners before that added an extension.

stuart45

If.there's no evidence of damp at present, it's difficult to know if there'll be a future problem. Even though the plan states the work was carried out because of rising damp, it's quite possible that the real cause was something else like condensation or penetrating damp. Owners are often persuaded by firms to do the whole ground floor. This often happens in house sales. The surveyor gets a damp reading, recommends a further damp specialist survey and the firm comes along and gives an estimate. 
The buyers get the money off the sale and decide the best time to do the work is straight away, before doing any decorating.
There was probably no real problem to start with, so they assume the work has solved the damp issues and tell everyone how good the work was.

ThisIsWeird

Emily_Joy said:

ThisIsWeird said:

Sit still. With drink in hand. Enjoy.
Chances are the problem has been resolved. 
There remains the possibility, I guess, that the house has been pre-sale redecorated in order to cover any issues, hence its current immaculate appearance. Does it look freshly done?
Can you find the previous sales partics on Zoopla?

I can find the previous sales partics on zoopla. What am I looking for? The previous owner installed new windows a few years ago and turned a lovely front garden with roses into a car parking place ... the owners before that added an extension.

It would be a very long shot, but perhaps signs of bubbling paint or stains above skirtings boards in any pic. Tho's it would be an incompetent EA to include that!

In short, the currently pristine house is immaculate for one of two reasons - the 'damp' issue was sorted, or because it has been freshly painted to cover it up. My 'guess' would be the former, and I don't think that I would have any issues about taking the house on. If the house is otherwise what you want, then just consider the 'worst case scenario' about damp, and what it would need to resolve - and ask yourself if that is 'ok'.

However, since there seemingly has been a historic case, I think a fair Q to ask your conveyancer to ask theirs is "Have there been any signs of recurring damp during your tenure?" Not quite sure what use this would be, but hey... :-)

Emily_Joy

stuart45 said:

Even though the plan states the work was carried out because of rising damp, it's quite possible that the real cause was something else like condensation or penetrating damp. Owners are often persuaded by firms to do the whole ground floor. This often happens in house sales. The surveyor gets a damp reading, recommends a further damp specialist survey and the firm comes along and gives an estimate. 
The buyers get the money off the sale and decide the best time to do the work is straight away, before doing any decorating.

Spot on! It looks like "damp proofing" has been done soon after the house was previously sold. Around the same time a new boiler was installed, one of the walls upstairs has been removed, and rewiring was done.

Only about 30cm of internal wall on the pictures from the previous sale is visible - the rest is behind the furniture. Those 30cm have no signs of damp

stuart45

A friend of mine used to own a Damp proofing and timber preservation company, and he said that the best time for a sale on damp proofing was when the new owners still had a few weeks left on their rental. Once people had been in their house for a few years, they were less likely to want the whole house done because of a bit of damp around the chimney breast in the lounge.
Dry rot was an easier sale, as he said that people were often terrified that a bit of wet rot in a skirting board was dry rot that was going to eat right through the floors and roof. He had a folder of photos showing ground floors, upper floors, roofs etc totally wrecked by dry rot.