Damp proof course

[charly]

Question number 2 lol

After being advised i got a damp proof guy in who suggested i have an osmosis wire installed then deciding i would get another price quote got another company in that do not do osmosis wire and have said it doesn't work and have advised that they would chemically inject the walls instead . I would imagine that injecting into a stone wall would be pretty difficult . Does anyone have any experience of this please that can help me decide which i need to go with ? Thank you

 

[mointainwalker]

First off Charly - are your walls damp ?

If they aren't, why do you need a DPC ? If they are damp, is there a reason for it e.g. leaking down-pipe, high external ground-level, condensation etc.

If you can't check this out yourself - and certainly for the cost/disruption potentially involved - I would consider paying for an independant surveyor who does not offer a damp-proof treatment service i.e. has no vested interest in steering you towards one particular solution.

You have so far contacted two damp-proofing suppliers who, surprise, surprise , have both said that what you need is what they happen to sell !

 

[stuart45]

mointainwalker is spot on with his comments. Thousands of people have been sold damp proofing systems that were totally unnessecary. A friend of mine used to work for BRE as as damp specialist surveyor. He said that the majority of jobs of rising damp that he was called on to give a second opinion on were not rising damp. On the ones that were the vast majority were caused that things like high ground levels etc. He also used to take out a van load of equipment out with him for the survey, not just a damp meter like many of the so called specialists use.
If you have an old solid stone wall the original finish would have been a lime render, which allows the walls to breathe.

 

[charly]

Tbh the house isn't damp anymore i have lowered the floors inside and the underfloor heating is in and screeded . my mate who is a groundworker has lowered the ground outside and lowered the drains . it says on the structural thingy that the house is built on stone but as he dug the floors out he has said it was mainly soil and that it may be an idea to sort some damp proof . i can post pic of what came out of ground
if that helps also being pointed and restoned at the min with lime ,cement and grano. thanks for replies

 

[mointainwalker]

Did you put in a DPC when you dug out your floor, and if (hopefully ) yes, how far up the wall did you take the sheet ?

 

[^woody^]

Electro-osmosis is a discredited system easily defeated by salts and water pressure

 

[charly]

Did you put in a DPC when you dug out your floor, and if (hopefully ) yes, how far up the wall did you take the sheet ?

well there was a layer of viscuiny stuff if thats what you mean ? it comes up to the screed ...

woody i didn't understand what you meant sorry

 

[mointainwalker]

Well no it's not what I meant. I was referring to a thick polythene sheet which is the usual - and I'm sure cheapest - type of DPC.

Who laid this viscous coating and did they tell you what it was and what it was supposed to do ?

Woody means that the reverse-osmosis system is junk .

I second that as I had a Rentokil one in a house I bought and still had damp problems and Rentokil weren't interested.

 

[charly]

i realise what the dpc is now mw i have got some to go under the stone facing on the extension. the ground worker laid the visquine for me before he poured the concrete .

thanks for simplifying what woody said also . my head is choka block with things i have to sort i fear my brain is on the point of exploding

 

[charly]

Electro-osmosis is a discredited system easily defeated by salts and water pressure

Woody what would you recommend that i do then put in the injected one or just leave as is ? cheers

 

[^woody^]

The first thing is to actually diagnose the problem, and then determine the solution. I wont repeat all the possibilities here, but part of it is determining if any existing DPC has failed or if the wall is aged, or if its another reason.

Some stone walls can become porous with age, or it may just be the mortar which is allowing water ingress. Stone (or walls) with voids or fractures will not take any injected fluid or cream, so this will be a waste of time on certain walls.

Or could it just be a case of ventilation and heating.

The big mistake people make with all these damp problems at ground level, is accurately determining what is causing the dampness in the first place