Damp

[Nefertiri]

A tenanted house (currently unoccupied) has had bad damp problems. Gutters, roof all o.k., and the pointing has been redone where damp seemed to be coming in through the walls. It really could do with a damp proof course but we just don't have enough time to do a full one involving removing paper, laminate flooring and needing to replaster and repaper and repaint as tenants are back in in a few weeks.

I've heard that there are other quicker ways to deal with damp, someone suggested it's possible to treat the outside with something (the walls end up white but its on the back so doesn't matter, and I've heard that there are other alternatives too.

Even something that will improve the situation for a year until the tenants move out and we can deal with it properly will be better than nothing.

Any suggestions please?

 

[Softus]

What are the symptoms of the problem you wish to solve?

 

[Nefertiri]

Damp walls, it seemed ok but the recent wet weather has highlighted the situation and mould is now showing through the wallpaper in places and the house actually smells damp.

 

[Softus]

Hm. Your problem is probably more complex than you think. For example, if the pointing is in good order then the water must be coming through some other way.

For now, to answer your original question, there are products (e.g. this one) that you can apply to brickwork to repel rainwater, but please heed the advice in the 8th answer on this page.

Also, see this page for an example of helpful advice on repointing.

 

[foxhole]

Mould would indicate a lack of ventilation.

 

[diy_darren]

I'd ask a damp proofing company to come around and do a survey for you (may cost around £30). They have a device which allows them to take moisture readings in various areas of the wall, so they can tell you if your problem is rising damp as well as penetrating damp or condensation buildup.

A chemical DPC (injected into the brickwork) will not help with penetrating damp or condensation buildup.

As already mentioned, mould is generally a sign of condensation buildup and lack of ventillation. It could be a result of water penetrating the brickwork though if the wall was getting and staying very damp for long periods of time.

If the problem is penetrating damp (water leeching through the wall) then you really need to find and fix the problem in the wall itself. IMO, other fixes are temporary and still require you to fix the original problem in the end.

Which room/s of the house is the problem visible in?

(my comments are based on my own experience treating damp issues in my own house, don't assume they are all correct!)

 

[JohnD]

start with ventilation.

have a look at
//wiki.diynot.com/building:condensation_in_houses

 

[Softus]

I'd ask a damp proofing company to come around and do a survey for you (may cost around £30).

Do not do this. A damp-proofing company will find damp and will attempt to sell you something.

Instead, pay a qualified surveyor to make an assessment.

A chemical DPC (injected into the brickwork) will help with rising damp...

What evidence do you have to support that wild and crazy assertion?

 

[diy_darren]

A chemical DPC (injected into the brickwork) will help with rising damp...

What evidence do you have to support that wild and crazy assertion?

I've changed my original post, as I was trying to point out that installing a DPC will not solve penetrating damp or condensation problems. Implying that a DPC will fix rising damp was wrong, my bad!

 

[Softus]

8)

 

[anobium]

Softus wrote

Instead, pay a qualified surveyor to make an assessment.

I am surprised at you Softus, you are very naive if you think that a surveyor, (I presume you are talking about a chartered surveyor) will carry out the necessary tests to check for the causes of damp.
In my experience you will find that he in turn will instruct a damp proofing surveyor to do the inspection and he will then incorporate those findings in his report and charge joe bloggs an arm and a leg for the privilege.

 

[Softus]

Please feel free to presume whatever you want.

 

[anobium]

Softus wrote

Please feel free to presume whatever you want

Is that your way of saying ,"I'm not sure what type of surveyor I was recommending".
If so, apology accepted.

 

[Softus]

Is that your way of saying ,"I'm not sure what type of surveyor I was recommending".

No.

If so, apology accepted.

Please feel free to accept any apology you find being offered.

 

[TheLastMan]

Softus wrote

Instead, pay a qualified surveyor to make an assessment.

I am surprised at you Softus, you are very naive if you think that a surveyor, (I presume you are talking about a chartered surveyor) will carry out the necessary tests to check for the causes of damp.
In my experience you will find that he in turn will instruct a damp proofing surveyor to do the inspection and he will then incorporate those findings in his report and charge joe bloggs an arm and a leg for the privilege.

Ignore this guy. An RICS qualified building surveyor will be able to pinpoint the source of a damp problem if asked. Most people's experience of a surveyor is the guy who spends 2 hours at your house doing a Home Buyer's report. Inevitably these won't cover a detailed investigation of every problem found. A building surveyor told to find out the source of a damp problem like this will probably spend 3-4 hours at the house and is likely to cost £400-£600.

If he thinks the problem is rising damp then he may get a quote from a contractor for you, but that is very different from using a contractor to diagnose the problem.

Persistent damp problems can lead to dry-rot. Fixing that is lot more expensive than half a day of a surveyor's time!