How do you know you've ruled out condensation (on the consistently coldest bit of the house)?

Sorry if I'm missing the point, but doesn't a French drain answer the original question?

Even if rising damp does exist, it's going to have to work bl**dy hard to rise that far.

https://www.heritage-house.org/damp-and-condensation/the-fraud-of-rising-damp.html

I like this chap's site blog and his YouTube videos

Photos of the inside and outside would be useful, I think. Also stick an RH meter on the floor by the wall and see what it says.

Will , thanks for the vid I'll check it out ,
I remember a BBC documentry years ago about the issue of falsely diagnosed rising damp and the debated around whether it actually occurs much.

Im familiar with the 'heritage' method of dealing with damp
French drains
ventilation
dealing with cold spots
breathable construction etc.
sometimes they still leave a problem the client doesnt want.

quick low down
9" london stock brick , north facing wall, pointed with weak sand cement mix by the looks of it
suspended floor , probably poorly vent
no insulation anywhere in the area
air tightness no exisitant
externally block paved sloping away from house with gravel smallish french drain against wall

Posted By: jamesingramquick low down
9" london stock brick , north facing wall, pointed with weak sand cement mix by the looks of it
suspended floor , probably poorly vent
no insulation anywhere in the area
air tightness no exisitant
externally block paved sloping away from house with gravel smallish french drain against wall

DPC?

Here is one I did last year

Thanks for inviting me to check for damp in the walls of your Victorian terraced home in Reading. You told me that you had received a survey, report and estimate from a damp proofing company and they had informed you that the whole of the ground floor of your property needed to have an injected damp course and to be replastered up to 1m high all round with waterproof plaster at cost of £4,250

I suggested that you allowed me to check for damp by drilling a series of 5mm holes 60mm deep low down in your walls, collecting the dust, weighing it, drying it in an oven at 120C and reweighing it. I would then be able to calculate the percentage moisture content in the walls.

The results were surprising as the previous survey with a good quality electronic damp meter indicated that high levels of damp were present in all the walls and indeed there was some evidence of this near the front door and in the kitchen where there had been a flat roof leak some years ago, this had been repaired.


The test results percentages for holes 1 to 9 were; 2.1, 1.4, 3.3, 0.5, 3.3, 2.1, 1.3, 0.25, 1.3 respectively.

The very low result of 0.25 was so low that I double checked it as it was behind your WC under the cistern in a single storey rear addition where we would normally find a higher level of moisture. I had never seen test results this low in terraced houses. The highest results could not be classed as damp and I recommended that you did not do the injected damp course or waterproof replastering as it was unnecessary. Cosmetic replastering in some areas was all that would be needed, saving a lot of hassle and £4250

The first test hole was behind the front door. The last test was only 1.3% was under the window by your stereo and the eighth behind the WC and usually the dampest place. I have never seen a result below 1% before in a terraced house.

The fifth and sixth results are both behind the bins in the kitchen where the roof leaked.

My recommendation was that no damp treatment need be carried out.

What water?

Well done, there is a whole industry relying on people being not like you.

Often on an easy win as a guarantee for work is frequently required by a mortgage company who have no interest in the work itself just the piece of paper.