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Is this rising damp?

Postby marie48 » Wed Nov 23, 2011 10:55 am

I am so confused about a damp patch area in an old property I bought two years. The surveyer said it was rising damp. The builder said to wait and see whether the damp patch will dry up in summer as he did some works on the roof and had made it airtight. The patch did dry in summer but last week on inspection it has got bigger and much worse. I got a damp specialist who did a survey and told me it is not risind damp but to check for blockage on the roof as his damp meter went beserk and pointed all the way to the roof. He is qualified with CSRT & CSSW and the company is reputable and registered with PCA, Trust Mark etc. I just do not know who to believe, they are both from reputalbe firms and one said I have got rising damp and gave me quote to put it right, that area has already got one and he said it has failed and the other one said it is not rising damp as the dampness starts one mt above the floor and he said rising damp does not just start in the middle of the wall. He said to check the gutters and go outside when it is pouring to send when they are defective. So much conflicting option from the experts, can somebody help me pl? See photo. Thanks
IMG_0334_1 (Small).jpg
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Postby welsh brickie » Wed Nov 23, 2011 7:35 pm

It is not rising damp,I would check for any external crack,It could also be a bridging of a wall tie,water will find the lowest point to enter a property so look above the window or door I can see in the picture.
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Postby marie48 » Thu Nov 24, 2011 1:27 pm

Thanks, is rising damp usually starts at the bottom? I am really surprised that two qualified surveyors gave me different report. There are several external cracks on the outside of the wall but was informed they were minor. I guess will have to fill them first and then replaster the wall. The previous owner has the window replaced, I wonder whether it has got anything to do with it. It is just I do not want to replaster the wall and then find it has not been improved and I have to have that area damp proof.
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Postby welsh brickie » Thu Nov 24, 2011 10:01 pm

strip off all the paper, back to the plaster and coat the wall with a PVA solution,this will seal the wall.It can used externally aswell, and dries clear
The pva can be bought at any builders merchants or diy suppliers and its very cheap.Paint it everywhere at least 3 coats over the cracks and see if the damp clears.
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Postby marie48 » Fri Nov 25, 2011 4:54 pm

Thanks, got the surveyor's report and has been quoted for rising damp course although he said it was rain penetration. It is over £850+vat and £110 for guaranteed protection insurance. The quote comes well over 1k and will cost more depending what he finds when he starts the work. Pl see whether this make sense to you as I have not got a clue, it looks he is doing the damp proof inside the wall. This is what he intends to do. A bit concerned about the plaster being contaminated whether it needs to be replastered to a specification due to the salts contents. and whether I am confident to tackle this myself. This is what he proposes to do.

Provide and fix 8 mm studded cavity damp proof membrane to all walls as
indicated on the attached Plan.
Re-plastering in accordance with the Company’s PLASTERING
SPECIFICATION for walls above ground.
Provide and fix 30 x 25 mm pre-treated battens, directly fixed to the wall. In
this instance, it will be necessary to follow the contours of the wall. In the
event that levelling tolerances are in excess of your requirements, then an
alternative method will be adopted. Any variation in costs will be brought to
your attention before we proceed with the change Specification.
Provide and fix 12 mm plasterboards to studwork and apply scrim to joints,
and skim using multi-coat skim plaster.

I also need to treat the skirking board with a wood preservative and refix into a PVCX damp proof membrane myself. Got no clue what to do!! Thanks a lot for your advice.
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Postby welsh brickie » Mon Nov 28, 2011 7:42 pm

HOW MUCH!!!!!!!!!!,Do not go with a specialist damp company report,It is not rising damp.He confirmed my suspicion of penitrating damp.
If you want to attempt the damp problem yourself,all you need is a silicone gun,Some clear silicone and some pva.Total cost about £20.Just scrape out ALL the cracks and fill with the silicone,wet your finger and smooth it into the plaster,
"Take your time",When its set 24 hours later, mix a solution of pva and water and paint the entire area,it dries clear so dont worry.You can also paint the wall on the inside aswell.
Now if you dont want to, or be able to do it yourself, get a friend who can do it for you,Or get a tradesman you can trust.
Speak to friends,work collegues and family members.get recommendations of builders they have used in the past,and ask to see their work,Its not serious so you can wait, and do your groundwork,Dont go with 1 quote get 3 .
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Postby marie48 » Tue Nov 29, 2011 12:48 pm

Thanks welsh brickie. That's the second quote, the first was over 2 yrs ago and it was not even that bad only a very small patch and he said it was rising damp and quoted over 1k. I am going to get them to requote and question their diagnosis. The builder is also coming to check the roof next week, he is very good but very expensive. I do not know whether I have posted the report and sketch of the damp area. Here it is again to give you an idea, the report & sketch are not allowed for me to download. This is really doing my head in but am glad that you said it is not urgent, the surveyor said the same. The report scares me esp about rot. Thanks a lot for your advice.

Our initial diagnosis is based on a visual appearance of the wall surfaces,
supplemented by non-destructive testing with the Protimeter Electric Moisture Meter.

Evidence of excessive moisture was noted to the walls indicated on the attached
Sketch Plan.

After consideration of the pattern of moisture readings found, and the general pattern
of dampness noted, we conclude that the dampness is due to suspected rainwater

• Contamination of plaster by Hygroscopic Salts.

• The ground level to the adjoining property is set above the internal floor and
damp proof course level. Consequently, lateral penetration, with associated
capillary rise of dampness, is occurring.

Where bridging of any existing damp proof course has been noted, the cause
of the bridging should be rectified. However, where rectification of the
bridging cannot be achieved, or proves to be impracticable for any reason, a
new damp proof course should be inserted into the wall above the upper level
of the bridging, and followed by re-plastering to the relevant section of our
Plastering Specification.

• Defective external rendering.

Current Building Code of Practice states that all render should stop short of
the damp proof course line. The render should be trimmed up and finished in
a bell mouth drip, in accordance with Paragraph 28.6 of BS 5262.

• Condensation caused by a combination of high humidity and cold surfaces.

• The left hand party wall has been dry-lined. This seriously restricted our

The true extent of the damp proofing works may be more than can be
currently determined, without removal of sections of the plasterboarding for
further testing, for which we would have to make a charge.

• Rain penetration has occurred, especially to the left hand corner of the
through lounge. If this is allowed to continue, decay is likely to occur in any
timbers that are persistently damp, or wet.

In particular, the lintels, dry-lining fixing timbers and sub-floor timbers are
considered to be highly vulnerable to Fungal Decay.

It was not possible to carry out a detailed inspection of the timbers. We advise that
the Client removes all restrictions, and that a detailed inspection be carried out. We
will, upon written instructions from the Client, return and make a detailed inspection.


The above findings are based upon the interpretation of results from a standard non-
destructive inspection; this, by necessity, has limitations. If you require confirmatory/
definitive diagnosis of our findings, then this can be undertaken by the use of
destructive methods of investigation: these will involve some damage and costs to

Fungal Decay is always associated with a high moisture content in timber, and,
therefore, timbers bearing in, or in contact with walls where moisture has, or may
have, penetrated, must be considered suspect.

It is essential that immediate steps be taken to eliminate the source of moisture
ingress identified, and that, thereafter, the building is maintained in a weatherproof

We have not inspected parts of the property that were covered, unexposed, or
inaccessible at the time of our inspection. We cannot give our assurance that any
such area is free from rising damp.


In order to overcome the problems of apparent Rising Damp / Hygroscopic Salts
referred to above, we have prepared a Specification of Remedial Work. This
Specification includes:-

• The prevention of Rising Damp by the insertion of a DAMP PROOF
COURSE, which

Is odourless and non-flammable, resulting
in minimum discomfort and danger to occupants.

Has the British Board of Agrèment Approval

• The removal and renewal of wall plaster, in strict accordance with the
Company’s PLASTER SPECIFICATION, in order to control future dampness
problems due to Hygroscopic Salts, thus ensuring:-

Minimum delays prior to re-plastering.
Speedy redecoration.
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Postby welsh brickie » Tue Nov 29, 2011 6:58 pm

I have read your report,Its hard to comment on just a photograph,but it does say that the ground level outside is higher than the floor inside.
This is a major factor of damp,but can be rectified,it does need the internal plaster removed and a buitumin paint used to seal the wall,they suggested injection.Dont really believe in it personally Ideally the outside ground needs lowering aswell if possible.If not, an ACO drainage system should be fitted against the exterior wall.
It also states a bell bead added to the outside,this is also true it deflects the water away from the wall.
So with the work stated, and the inspection report on the cause of dampness.You can present this report to your insurance company,Its possible they will foot the bill for you.
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