Rising damp advice please

In London, DPC became mandatory in 1875.

Most other town and cities followed soon afterwards.

Some better builds had them before then.

Clean unplastered brickwork does not absorb water very high because each course of mortar acts as a partial barrier, due to the change in pore size. Capillarity will pull water from large pores to small, but not from small pores to large.

Yes we have to take notice of professionals but it sadly has to be with a pinch of salt a lot of the time. Take time to gain knowledge on the various forums there are, even go to a library and look at period property renovation books (there are lots!) so that you can smell bull when builders/tradesman talk to you.

Once they realise you have some knowledge it actually becomes easier talking to them.

I had a funny situation with a builder who was the sort who probably would have preferred my husband to talk to him, we were discussing lime plaster, he was very full of himself and asked "do I know what lime plaster is and when it is used". We were standing by a recently lime plastered wall - builder said, this is lime plaster waiting for its topcoat, you can see the hair which has been mixed in with the plaster. I know I replied, I mixed the plaster and plastered the wall!

It's worth bearing in mind that older houses don't have damp proof courses at all and still don't have damp.

How much was he expecting your house to move to break slates 🤔

I think you have received the main points.

Damp is usually caused by building defects, such as leaks around chimneys and windows, or pipes or drains. Sometimes it is caused by soil or paving levels being raised against the wall and bridging the dpc.

Or by insufficient ventilation, such as blocked fireplaces or airbricks, or inadequate steam extraction in bathrooms

Or by excessive moisture load, such as damp washing draped indoors or steamy showers without adequate exraction.

Interestingly, not one of those sources of water will be repaired by injecting silicone into walls or painting damp proofing chemicals onto them.

Most houses in Britain less than two hundred years old were built with a damp course, most often slate. Slate lasts hundreds of millions of years and does not wear out.

Anybody who tells you your damp course has "failed" or that silicone injections will cure your damp should be asked to leave.

@Freespirit44 Periodproperty.co.uk is a good forum. Post on there, they have a depth of info regarding issues such as you have.

Well done for not going ahead with the other company - good call.

Yes as a pp has said, vents can help but can also cause as many problems. It is a fine balancing act to allow the house to breathe but not to get too many flunctuations in temp. Heating in older houses is best left on for longer periods of time at a lower temp.

so I had to give an answer by yesterday evening to be able to retain a slot with the company

Dodgy high pressure sales tactics are the last thing you want from a company that will be doing work on your home. Avoid like the plague.

Just be careful that vents don't make the house colder because you will get even more condensation. It's a real balancing act!

I agree with PP, check out the Facebook groups they mention.

It’s not rising damp. Rising damp does not exist. It always, always water ingress by way of gutters, roof, windows, doors, pipes, chimneys, failed DPM, non-breathable materials, or condensation.

The period property DIY and renovation groups on Facebooks are extremely helpful in troubleshooting these issues.

Do not do it. It sounds like the house needs to breathe not some expensive "remedy" work, prescribed by a company that does such work. Basically moisture in the atmosphere inside is probably condensing on cold areas of wall and causing the problems that you can see.

Lots of factors could be involved. Look into ventilation (could put PIV in the loft, a few hundred quid), decent extraction from kitchen and bathroom, plaster and render preventing the walls breathing, failed (wet) cavity wall insulation can be a nightmare, dodgy gutters/downpipes/gullies, house is too cold inside...

It will take a while but you need to do some reading and start a process of elimination.

Ok, slightly longer than I thought! The advice you have received from many on here still applies though - it is not rising damp, allow nobody with a damp meter near it and do not get quotes from anyone who sells damp products.

You will get it sorted I am sure, many of us have had damp houses and have got them sorted, I would guarantee 99% of us have not had rising damp!

As above, rising damp is a myth. And anyone waving a damp meter about is not to be trusted.

Before paying out any money I'd want to know that water isn't leaking in. Having the chimney pointing and flashing checked would be an obvious place to start.

Rising damp is a myth. Damp meters don’t measure damp, just conductivity - and you have no idea what material it’s reading. Put a damp meter against lead paint and watch it go wild…

You invited a damp salesman into your home and - surprise surprise - they want to sell you damp proofing products. Do not hire them.

You’ve probably got a combination of a leaking chimney and high levels of humidity indoors. Buy a decent dehumidifier (£150) and a few hygrometers (£15), get your relative humidity under 50% and see if it dries out. Then ask around to find a local reputable roofer to take a look at your chimney and gutters.

I’d get different quotes even if you need to pay the quotation fee as to give different options/opinions on how to treat.

Does your house insurance not cover the work required, also you’ve said you just moved in, how long ago and did you have a in-depth survey done of the property?

As you have not long moved it - I would actually do nothing for a short while and see what happens to the areas with the issues, maybe with the exception of getting the chimney checked.

You may find once the house is lived in and CH switched on, some of the issues may dry out, if they remain then you can monitor if they get worse when it rains - this will give you more info as to what may be causing the problems.

The last thing you want to do currently is to pay a lot of money for damp proof courses etc until you know exactly what is wrong and how to get it fixed.