Damp advise please

[micjamwat]

Hi, I have had an offer accepted on a 2 bed victorian mid terrace which has some very obvoius damp. The seller had an inspection carried out by and damp proofing firm and unsuprisingly they have diagnosed rising damp. They have recomended a dryzone treatment and re-plastering but after what I have read on this site this sounds innapropriate.

The most obvious damp is on the adjoining wall below waist hight where the plaster is crumbling off, the property has been vacant for a few months and was previously a rental, there apears to be a concrete floor, the condition of the house is generally shaby but is not about to fall down, the windows are single glazed with wooden frames and the chimneys apear unblocked.

Any advise greatly appreciated

Michael

 

[Pford75]

There used to be a rather good 'sticky' on damp...but this seems to have disappeared.

Others are more expert on the subject than myself, but thought i'd chip in and bump you back to the top...maybe someone else will correct me if I go wrong...


Basically, you need to do 3 things:

1. Remove any source of water (eg. leaking gutter outside, stop rainsplash from a concrete path etc.)
2. Ventilate (If the house has been empty, this probably hasn't happened. We had a tenant in one of our lets who stuck a tumbledryer (unvented) in the bedroom and then complained of black mould on the walls!) Hopefully the house hasn't been hermetically sealed with double-glazing, carpets and too much draught proofing. Some level of draught is not necessarily a bad thing
3. Get some warmth into the room

I would steer clear of any treatment, at least until you have had chance to live in the place for a while (since this could solve the problem).

I'll leave others to comment on the floor

 

[Lime]

The thread for damp.

http://periodproperty.co.uk/forum/viewforum.php?f=6

 

[DaveBrigg]

I suspect that damp in an adjoining wall is less common, since it is less likely to be caused by rain. Is the 'outside' wall dry. Although you haven't moved in yet, it may be worth trying to speak to your future neighbour to see if they have a similar problem on their side. What you don't want to hear is that they did have damp on that wall until they rendered it in cement (as insisted on by most damp-proof companies). If this is the case, you have limited options.
Good luck

 

[micjamwat]

Thanks for the advice. It is a mid terrace and the most obvoius damp is only on one adjoining wall, if the neibours have 'treated' their side, where would this leave me?

Thanks

Michael

 

[MdB]

Is the terrace on a Hovis style hill or is it on the flat? What I'm getting at is the relative floor level heights between your property and the one next door? If their floor level is a lot higher then you could be getting penetrating damp through the wall.

 

[micjamwat]

The street is pretty flat, I would say the neighbours house is on the same level.

 

[MdB]

Possible causes of your damp (that I can think of, there will be others)

1) Burst pipe in wall - Would have thought this unlikely for a shared wall.

2) Condensation - Would have thought that the would have been more likely on the outside walls.

3) Swimming pool in neighbours front room - well it is possible.

4) Rising damp - Possible if the water table is very high

Solutions

1) Ventilate & Heat & Dehumidify - All easy and cheap to do and well worth doing for minimum 6 months to see what happens.

2) Remove plaster from wall and then do 1) - Will give wall chance to dry out.

3) Tank - Will increase the moisture levels in the wall which won't do the wall much good and will probably cause a damp patch in the neighbours property.

4) Dry line - Won't cure the problem but will hide it. Make sure there is some ventilation to the cavity if possible and expect the cavity to turn into a mold paradise.

5) Injected DPC - If it is rising damp then it might be an option. A lot of people here think they are a con and I would generally agree.

Most peoples damp problems in the past have an obvious cause, yours is not so obvious so the best action is difficult to suggest.

Caveat - I am not a damp expert though I have read up on a lot looking for solutions to my damp problems - which now seem to be cured.

Edit - How does joint between the concrete floor and the wall work? I assume the concrete floor is a later addition so it is possible that a layer was just placed on top of whatever was there before. If the plaster wasn't removed from the wall before this was done then the plaster will act as a good route for the moisture to travel up the walls. This happened to us here giving us damp 200mm up the internal walls.

 

[micjamwat]

At the moment I'm thinking the concrete floor sounds like the culprit. Although there is wood-chip paper and several layers of paint on the wall so maybe just stripping the wall and letting it dry out will sort it. I really need to decide if I want to buy this house so do I want to risk it being the worst case scenario (digging up the floor or injecting a dpc)? I don't think there could be a burst pipe as I can't think where it would be going.

Thanks

 

[micjamwat]

I have just been next door and they have only just moved in but have no obvious signs of damp on their side. However, their chimney is roughly in line with the worst of the damp. Am I right in thinking that if their chimney needed re-pointing or the lead has gaps this could be causing the problem?

Michael

 

[Flyfisher]

The plot thickens!

If there's a problem with the chimney flashing/pointing then I would look for damp problems higher up, possibly upstairs or in the attic? Have you been able to look inside the attic?

As the damp problem seems to be at waist height on the ground floor then perhaps water is simply falling down the chimney. Is the pot capped in some way? Is your neighbour using the chimney or is it bricked up - basically, has it got a good source of ventilation?

 

[micjamwat]

The neibours have a wood burner and have recently had the chimney swept. They have only recently moved in so it may have been unused untill recently. The chimneys apear to have some kind of cap, they are what I think of as typical victorian chimney pots (if there is such a thing). There dosen't seem to be any damp in the attic.

 

[Flyfisher]

Perhaps there's no effective ventilation within the chimney void so, effectively, the chimney space could be sealed at both ends?