Rising damp in internal wall?

Londonfirsttimer

Last year I bought a leasehold flat on a council estate. It's on the ground floor, though the ground slopes away and there are garages under the bedroom and living room. It was built in 1970, cavity walls, concrete floor. I was thinking about getting a full survey but the mortgagee went ahead and just got a standard valuation before I had made up my mind! (before you chide, I got the place at a really good price so even if it's an expensive repair I'll come out of this ok, it'll just be stress and time)

I suspected there may be some damp issues as:
1) a corner of the bedroom wall was tiled (though I've had tiles fall off a properly damp wall in the past)
2) the hallway only had wallpaper to halfway down the wall

I thought most of the damp problems were due to it being rented out and probably not looked after/heated properly.

I redecorated the bedroom and discovered the air vent was packed with insulation. Removed that, removed the tiles, there hasn't been a problem since except when I had a house sitter over Christmas who left the bathroom door open after showering, the kitchen door open while boiling water, and dried laundry in the room. This resulted in a small puddle on top of the skirting board (she said "you thought there might be damp but there hasn't been a problem at all!). There hasn't been a problem since she left.

Now I'm onto the hallway and I've removed some of the paint on the lower half of an internal wall (the upper half was papered) to reveal a semi-circular damp spot from the skirting board up. There is some mould and smell. There is a crack in the plaster near - but not exactly on - the centre of the semi-circle.

The other side of the wall is a cupboard that used to have a hot water cylinder in it. I had the washing machine moved in here in Jan (by a plumber who did my bathroom). There are also radiator pipes going through to a radiator on the hall wall. I did have leaks in the system but put some leak sealer through in Jan and the boiler hasn't lost pressure since.

Could this problem just be historic, from an earlier leak that is now gone, and now that I've removed the paint it will dry out?

Or is it the dreaded rising damp? It's a couple of metres away from the external wall so it would be coming up through the concrete, maybe at the back of the garage (not my garage so I don't know how far it goes back).

The council is sending a surveyor but not for another couple of weeks. Until then I get to worry! But it will be interesting to see if it dries out at all in the next couple of weeks.

brightontraveller

Londonfirsttimer wrote: »

Last year I bought a leasehold flat on a council estate. It's on the ground floor, though the ground slopes away and there are garages under the bedroom and living room. It was built in 1970, cavity walls, concrete floor. I was thinking about getting a full survey but the mortgagee went ahead and just got a standard valuation before I had made up my mind! (before you chide, I got the place at a really good price so even if it's an expensive repair I'll come out of this ok, it'll just be stress and time)

I suspected there may be some damp issues as:
1) a corner of the bedroom wall was tiled (though I've had tiles fall off a properly damp wall in the past)
2) the hallway only had wallpaper to halfway down the wall

I thought most of the damp problems were due to it being rented out and probably not looked after/heated properly.

I redecorated the bedroom and discovered the air vent was packed with insulation. Removed that, removed the tiles, there hasn't been a problem since except when I had a house sitter over Christmas who left the bathroom door open after showering, the kitchen door open while boiling water, and dried laundry in the room. This resulted in a small puddle on top of the skirting board (she said "you thought there might be damp but there hasn't been a problem at all!). There hasn't been a problem since she left.

Now I'm onto the hallway and I've removed some of the paint on the lower half of an internal wall (the upper half was papered) to reveal a semi-circular damp spot from the skirting board up. There is some mould and smell. There is a crack in the plaster near - but not exactly on - the centre of the semi-circle.

The other side of the wall is a cupboard that used to have a hot water cylinder in it. I had the washing machine moved in here in Jan (by a plumber who did my bathroom). There are also radiator pipes going through to a radiator on the hall wall. I did have leaks in the system but put some leak sealer through in Jan and the boiler hasn't lost pressure since.

Could this problem just be historic, from an earlier leak that is now gone, and now that I've removed the paint it will dry out?

Or is it the dreaded rising damp? It's a couple of metres away from the external wall so it would be coming up through the concrete, maybe at the back of the garage (not my garage so I don't know how far it goes back).

The council is sending a surveyor but not for another couple of weeks. Until then I get to worry! But it will be interesting to see if it dries out at all in the next couple of weeks.

On wall mark extremities of suspected damp with pencil see if it expands, contracts etc. Under pipe work place tissue paper, talcum powders etc on floor leave and see if any marks appears on it from dripping / leak etc, Remember un-insulated pipes can get condensation on them this will drip down to lowest point,

If there are extractors make sure they work, vents not blocked etc if you don’t have them add them to bathroom , kitchen etc ex local authority properties often don’t have them or those that do are often not working or not sufficient especially if you dry clothing indoors, have showers and boil lots of food...

changed_username

I am no expert in this situation at all but there are a few things that jump out at me if you are looking for a dehumidifier.

These are:

* Mould
* Smell
* Drying clothes indoors

Almost all dehumidifiers get rid of mould if used correctly however I would choose a desiccant dehumidifier as they are more cost efficient than compressor dehumidifiers. Desiccants are generally quieter in operation as well.

Mouldy smells can be removed if the dehumidifier has an ioniser.

For drying clothes you need a dehumidifier that has a 'turbo' or 'laundry' function pus it is handy if there is an air outlet/louvre which can be pointed at the clothes during drying.

The two dehumidifiers with these features that I would recommend are the Meaco DD8L Desiccant Dehumidifier and the EcoAir DD122MK5 Desiccant Dehumidifier.

There are plenty of reviews about these dehumidifiers on Google.

rich13348

I am no expert in this situation at all but there are a few things that jump out at me if you are looking for a dehumidifier.

I didn't realise the OP asked about dehumidifiers.

changed_username

rich13348 wrote: »

I didn't realise the OP asked about dehumidifiers.

You are correct, the OP didn't.

However if the damp patch is historic and still smells then a proper dehumidifier is one of many solutions of getting rid of the smell and remaining damp.

Also drying clothes indoors is a big no, no unless the correct dehumidifier is used.

Drying clothes indoors increases humidity levels by up to 30% providing an ideal breeding ground for mould spores especially Aspergillus Fumigatus which can cause permanent respiratory damage.