Potential purchase/apparent rising damp/cause for concern

[lholman]

All,

I hope you may be able to shed some light/give some advise as to my next course of action. I have recently had an offer accepted on a turn of century brick built property in East Sussex (Brighton). The property is end of terrace and it’s suspected that the main walls of the building are 9” (225mm) solid brickwork. The walls externally are rendered which are painted and conceal the wall construction meaning there is no visible insitu damp proof course.

I have commissioned two individual damp proof reports but after reading quite a few articles on this forum I am in no doubt they will all come back suggesting required work. The first report which was (strangely!) commissioned by the Estate Agent, apparently they do this as standard for the majority of period properties but my doubt is that it was done after a previous survey identified the requirement.

The main areas of concern I have, taken from both the initial two reports (awaiting detail from the last which is being completed today) and a number of viewings and inspections by my self and family are as follows. It is worth noting that the property doesn’t smell of damp and there is no visible sign of damp walls on the ground floor. It is of a standard 2 up 2 down construction with a hallway against the party wall separating the living room and party wall:

-The first report has identified through the use of a Protrim moisture meter that there is proof of rising damp and subsequent preventative damp proofing is required along all accessible areas of the party wall and some area of the internal wall between the hallway and living room. Due to cupboards and fittings in the kitchen it was not possible for the report to include the remaining stretch of the party wall into the kitchen, this is obviously of some concern as the main reason given for the rising damp is that “the adjoining property ground levels are higher than the subject property internal floor levels” this would seem to suggest that the complete length of the party wall may need preventative damp proofing is needed at all?
-The second report has not identified any remedial damp proofing required on the party wall, but has identified that the whole internal wall between the hallway and the living room needs treatment.
-One of my major concerns is as to why three walls within the Living Room are dry lined. Although this is a commonly used method to legitimate DIY’ers/Builders etc? Obviously this dry lining prevented the walls being tested internally for rising or penetrative damp during the any reports, is my only way of investigation this to do/get done a drill test? The current vendor says the walls were dry lined when he bought the property 8 years ago.
-There is also some gable end damp staining observed in both bedrooms from what seems to be ongoing and / or historical rain water penetration (according to the report). I am inspecting this separately but wonder if potentially cracked rendering on the gable end wall would amplify any potential damp problems, letting in water and trapping it behind the render.

Any views or ideas on my best method of attack would be greatly appreciated, I am under considerable pressure from the Estate Agent about moving forward with a survey which I am arguing will give me no more insight as to the (potential) damp problem on the ground floor.

Kind regards,

Lloyd

 

[Nemesis]

Was those reports written by 'surveyors' who install chemical injection damp proofing by any small chance?

Have you not got a physical damp proof course in the building - it would be quite usual for a property of this age?

 

[lholman]

Nemesis,

Yes they were commisioned by companies that sell those solutions, I am just about to speak to a friend of a friend who is a RICS surveyor and get his opinion as well.

As stated from the first report due to the rendering of the property there is no evidence of a damp proof course, even though the vendor seems to think there is a slate dpc. Do you mean its usual for a property of this age TO have one ?

Thanks,

Lloyd

 

[Gervase]

Turn-of-the-century properties would usually have a slate DPC.
if the soil outside the house is higher than this DPC, then that would be a cause for action, as would the DPC being bridged by external render or cracking and letting in water.
Both are usually put right fairly simply without recourse to 'damp proofing' internally.

To have a wholly internal wall regarded as damp is unusual. It may simply be that the house has been empty for some time, the fabric has cooled and, at this time of year, condensation settles if you so much as breathe in a room. I would wait until you've lived there for a month or so before doing anything about that. It will almost certainly disappear!

What sort of floors do you have - are they wooden with an air-gap underneath or are they solid? And does your neighbour on the other side of the party wall have the same sort of floor? If there is damp, it could be from somethng as simple as a lack of ventilation under your floor (which would also encourage rot in your timberwork, so would need to be addressed)

 

[lholman]

Thanks for your time and obvious experience Gervase, my responses are below:

Turn-of-the-century properties would usually have a slate DPC.

That's what I was led to believe. I suppose chipping away some of the render would confirm this?

if the soil outside the house is higher than this DPC, then that would be a cause for action, as would the DPC being bridged by external render or cracking and letting in water.

I know the soil level is high outside the property but am not sure its that high, at the front it comes up to the bottom (almost over) a ventilation brick and at the side of the property (gable side , N/W facing end of terrace) there is a significant height of concrete as a base of the garage and forming the driveway which I believe could be covering any ventilation bricks and also bridging the DPC, however this will involve some serious inspection which I doubt can be done before the purchase. On a positive note we are planning to demolish the garage (free standing but butted against the house) and the driveway to lower the ground level and make a larger garden area.

It may simply be that the house has been empty for some time

The house isn't vacant, it is lived in at weekends only and has all furniture present, however I suppose this means there is no ventilation during the weekdays which could be a contributer. Would it be worth getting the vendors aggrement to do the old tinfoil test on the walls to identify damp or condensation?

What sort of floors do you have

Suspended with an air gap, as mentioend above I am concerned that there is not sufficient ventilation uner the floor, I think this may also be exagerated by a solid brick extension at the back of the property which may have blocked up any existing ventilation bricks for the hallway floor, I also didn't notice any at the front door and I believe the path buts straight up to the property.

does your neighbour on the other side of the party wall have the same sort of floor?

I'm not sure, I was thinking of knocking or dropping a letter through the door of the neighbour.

it could be from somethng as simple as a lack of ventilation under your floor (which would also encourage rot in your timberwork, so would need to be addressed)

I think this has higlighted an area of investigation. In actual fact the living room floor is stripped boards but the hallway is laminate, I wonder if this is covering up an issue? When asked the vendor said his mate had a job lot of laminate and did he did the hallway and kitchen at the same time.[/quote]

 

[Mark]

what sort of heating is in use - if its older people using gas fires full blast at the weekends then I would expect there to be very damp air as a matter of course. leading to condensation.

 

[middi]

I think you may have answered some of your own question here.

If the Dpc is bridged, it might as well not be there

If the air bricks are partially blocked and possibly inadequate, it has to be addressed, equally the raised external soil level should be 6 inches below dpc min.

If you are not so sure about the external condition of the render/pointing as well, the best thing to do is reduce your offer in light of the current reports to allow for worst scenario of repairs.

I would not have thought that a turn of the century brick building would require additional dpc treatment.-it is useless in anyway.

 

[NT]

quote="lholman"

> The property is end of terrace and it’s suspected that the main walls of the building are 9” (225mm) solid brickwork.

It would help to know what wall construction(s) were used.


> I have commissioned two individual damp proof reports

It'll be interesting to compare the 2 damp reports, see how much they contradict each other.


> but my doubt is that it was done after a previous survey identified the requirement.

surveys dont normally identify the requirement for a damp survey, they just state it as a matter of course. Its an ass covering exercise.


> It is worth noting that the property doesn’t smell of damp and there is no visible sign of damp walls on the ground floor.

Then theres no ground floor damp problem.


>-The first report has identified through the use of a Protrim moisture meter that there is proof of rising damp and subsequent preventative damp proofing is required along all accessible areas of the party wall

this is nonsense at every turn. Resistance meters dont measure moisture, and moisture on a wall doesnt mean a damp problem anyway. Rarely are damp problems anything to do with rising damp, other than in salesmen's minds, and finally damp proofing is not an appropriate way to resolve damp problems in 1900 properties.

These people are simply salesmen pedalling pseudoscience, and will tap you for whatever they think they can get.


> -The second report has not identified any remedial damp proofing required on the party wall, but has identified that the whole internal wall between the hallway and the living room needs treatment.

Youre taking this sales line too seriously.


> -One of my major concerns is as to why three walls within the Living Room are dry lined.

because its quicker than wet plastering, thus cheaper.


> Although this is a commonly used method to legitimate DIY’ers/Builders etc? Obviously this dry lining prevented the walls being tested internally for rising or penetrative damp during the any reports, is my only way of investigation this to do/get done a drill test?

You've already said theres no problem with the ground floor, so no test is needed.


> -There is also some gable end damp staining observed in both bedrooms from what seems to be ongoing and / or historical rain water penetration (according to the report). I am inspecting this separately but wonder if potentially cracked rendering on the gable end wall would amplify any potential damp problems, letting in water and trapping it behind the render.

bingo. The other common cause is faulty rainwater goods.


> Any views or ideas on my best method of attack would be greatly appreciated,

Check the usual causes with the upstairs wall problem, ie look at roof to see if it leaks, check gutter isnt blocked, downpipes blocked or corroded through.

Forget the nonsense with downstairs, you need to get far more cynical.


NT

 

[lholman]

Thanks for the concise responses to both middi and NT.

middi:

If the Dpc is bridged, it might as well not be there

If the air bricks are partially blocked and possibly inadequate, it has to be addressed, equally the raised external soil level should be 6 inches below dpc min.

These will be the first jobs on the list if and when we get the house.

If you are not so sure about the external condition of the render/pointing as well, the best thing to do is reduce your offer in light of the current reports to allow for worst scenario of repairs.

I am arranging a friend of a friend (a surveyor) to tell me what he thinks of the wall then am going to get a couple of quotes for re-rendering if required.

I would not have thought that a turn of the century brick building would require additional dpc treatment.-it is useless in anyway.

I agree with you now I am better informed. Guess what? The 3rd damp report came back with no damp proofing requried, he mentioned he thinks there may be a slight condensation issue and that is really it.

NT:

It would help to know what wall construction(s) were used.

Apart from knowing its solid brick work as stated before what else do I need to ask, are you refering to the type of mortar used?

It'll be interesting to compare the 2 damp reports, see how much they contradict each other.

Now I have the result of all three reports they all contradict each other as follows:
Report 1: Remedial damp proofing required along half of party wall and some of the internal wall quoting a price just shy of £1000.
Report 2: Remedial damp prooofing required along the compelte internal wall, nothing required on party wall.
Report 3: As stated above no damp proofing is required, he said he believes there is a pretty usual condensation issue if anything. He also thinks the other two companies were just after some work.
I have quotes within £50 or each other, both just shy of £1000, however

As stated before hand they couldn't do any further testing of the outside facing living room walls due to the dry lining.

they just state it as a matter of course. Its an ass covering exercise.

Thats good to know, looks like I haven't waisted too much time and energy so far then.

Resistance meters dont measure moisture

I keep hearing this and now feel far more confident investigating via other means and using common sense instead.

and finally damp proofing is not an appropriate way to resolve damp problems in 1900 properties.

Have we basically covered this above or are there any particular reasons for this?

pedalling pseudoscience

Going to re-use that quote, I love it.

Youre taking this sales line too seriously.

Unfortuantely due to my lack of knowledge/experience I was relying on them giving me honest feedback, however I now know after commisioning 3 reports and discussing with everyone on this forum that the reports must be taken with a pinch of salt.

because its quicker than wet plastering, thus cheaper.

Very valid point, I hadn't thought of it that way, however I would still like to get behind it and have a look. If we go ahead this will definitely be Job 2 on the list after the outside/ground work.

Check the usual causes with the upstairs wall problem, ie look at roof to see if it leaks, check gutter isnt blocked, downpipes blocked or corroded through.

Looks liek thats an addition to Job 1.

Thanks again everyone for your continued feedback, it is seriously appreciated.

ll

 

[NT]

quote=lholman, NT

>>It would help to know what wall construction(s) were used.

>Apart from knowing its solid brick work as stated before what else do I need to ask, are you refering to the type of mortar used?

IIRC you said: "it’s suspected that the main walls of the building are 9” (225mm) solid brickwork. The walls externally are rendered which are painted and conceal the wall construction"

which implies to me that its construction is guessed at but not known. Be aware that it is routine practice in many circles to merely assume old properties are 9" solid walled, when in reality many are not. In fact its quite normal to find period houses with a multitude of different wall types in the one building. Even a small 4 walled house might have 4 or 5 wall types, often some deliberately concealed.


>>It'll be interesting to compare the 2 damp reports, see how much they contradict each other.
>Now I have the result of all three reports they all contradict each other

enough said


> As stated before hand they couldn't do any further testing of the outside facing living room walls due to the dry lining.

FWIW its actually easy to dampmeter test the walls behind dry lining, but it would be an extra 5 minutes work. Draw your own conclusions.


>>and finally damp proofing is not an appropriate way to resolve damp problems in 1900 properties.

>Have we basically covered this above or are there any particular reasons for this?

I think this has not been covered above, no. Its a long story but in brief the methods of damp proofing used on new builds are inappropriate to period buildings, most of which handle damp in a significantly different way.


NT

 

[Johneds]

Now I have the result of all three reports they all contradict each other as follows:
Report 1: Remedial damp proofing required along half of party wall and some of the internal wall quoting a price just shy of £1000.
Report 2: Remedial damp prooofing required along the compelte internal wall, nothing required on party wall.
Report 3: As stated above no damp proofing is required, he said he believes there is a pretty usual condensation issue if anything. He also thinks the other two companies were just after some work.
I have quotes within £50 or each other, both just shy of £1000, however

Very consistent then!

 

[Nemesis]

So - why are three walls dry lined?

And were any of these diagnosed as having 'rising damp'?

 

[lholman]

According to the vendor, on the groud floor they are to "dry lined in order to rectify defective plasterwork, and have subsequently been decorated" and on the first floor on one particular wall "dry lining is to conceal plumbing and electrical wiring". The second comment I do believe as it is the party wall and the property was previously (around 10 years ago) converted to 2 flats then turned back again as retrospective planning permission was not gained.

ll