damp in old house

waitingforBB

Greetings all,
I've a problem with an old (1940) house which has solid concrete walls for the most part. There is an extension which is cavity block.
Problem is damp. In the bedroom and lower box room there is a build up of black mould on the wall. I assume at this stage its because there is no vent in the rooms at all?

If I drill a ventilation hole into the external facing wall will this improve / rectify?

I'll scrub off all the mould and paint with a blocker but I want a perm solution. Should I look to slab / dry wall internally with a membrane or something?

dont think the problem is due to leaks / external problems (although the windows of 20 years or so have no drip vents or anything).

My parents house, so want to sort it for them.
recent BER rated it as D, but no mention of how to improve the damp problem

Thanks

BryanF

My parents house, so want to sort it for them.
recent BER rated it as D, but no mention of how to improve the damp problem

1. the BER does not deal with such issues, was the BER assessor an engineer or architect? as they could advise you on the cause of your mould.
2. what work were you getting done that you needed a BER?

you are confusing these issues: mould cannot grow with out moisture, but this miosture is not necessarily due to damp penetration and as you've explained more likely a lack of ventilation, coupled with poor insulation


may i ask a few questions to narrow down this discussion:

waitingforBB wrote: »

Greetings all,
I've a problem with an old (1940) house which has solid concrete walls for the most part. There is an extension which is cavity block.
Problem is damp. In the bedroom and lower box room there is a build up of black mould on the wall. I assume at this stage its because there is no vent in the rooms at all?

3. so you have dampness in an 1st floor room and a ground floor room?
4. are both damp patches close to ceiling levels or are any of them at floor level?
5. have you pulled out any wardrobes lately, is there damp in behind them as-well?

If I drill a ventilation hole into the external facing wall will this improve / rectify?

yes from what you've said, there is certainly the need for a wall vent or window vent.

I'll scrub off all the mould and paint with a blocker but I want a perm solution. Should I look to slab / dry wall internally with a membrane or something?

internally dry-lining may just hide the problem, you do not want to do this, mould leads to health issues, and imo is worse if hidden behind dry-lining.

dont think the problem is due to leaks / external problems (although the windows of 20 years or so have no drip vents or anything).

if its not due to leaks etc. imo (this is without an inspection) its is a combination of a lack of ventilation, high internal moisture (install good mechanical extract fans in bathrooms and kitchen) and a lack of insulaiton.

I would recommend that you externally wall insulate (EWI) from foundation to integration with the attic insulation, install new windows in new position overlapped comfortably with the EWI.

if the house is 70 years old it may be time for some internal refurbishment this allows you options other than the installation of wall vents. going a step further, (depending on you home and house type) could be to improve the air-tightness and seal any penetrations. you could then install a demand controlled ventilation system (or depending on the air-tightness results a mechanical ventilation system with heat recovery (MVHR).

MicktheMan

Have a look at this previous thread. As BryanF says, it's more than likely that internally generated moisture, lack of ventilation, heating and insulation are the issues to be tackled. Unfortunately, there's no "silver bullet".

Gareth2011

Hi all,

OP are you sure they are mass concrete walls? My house was in built in 1940's also and before I bought it back in 2006 my neighbours son owned it. I asked my neighbour what type of walls were in the front (original house) and he told me solid concrete. I thought it sounded strange as i never heard of a solid concrete wall. I looked by the condition report that was done before we bought the house and that say 215 solid block. If like mine your too is solid black and its rising damp you can get a dpc injected into it. There is one you can do yourself and you just use a normal silicone gun for it. Its called "ultracure" damp store in dublin do it and I also found it on ebay too. cheap but effective than calling in professionals to do same thing.

waitingforBB

Thanks for the replies guys, much appreciated.
My parents applied for an insulation grant (under warmer homes scheme?).
Some great guys came out and insulated the attic, they also provided energy efficient bulbs and tested the walls to see if they could provide cavity insulation. The found that the main building wasnt suitable, but the Kitchen (was originally an old skullery (sp?) type) was ok and they pumped insulation in there. The BER was done as part of this some weeks ago.

There is no problems visible in the kitchen (newer structure and there are extractor fans.

Its a two up two down terrace town house and the problems I'm seeing are on the inside of the external walls (actually mainly the walls at the front of the house. Black spotty patches (I'll post a pic if I can tomorow) distributed evenly over the wall, floor to cieling in the downstairs box room (used as a bedroom now). The other downstairs room (living room attached ot kitchen shows no problems. However the room directly above the box room is a small bedroom (was mine for the first 20 years of my life) shows similar signs, but mainly around the window. I remember growing up that in the winter water would run down the walls when the heat was on and subsequently freeze.

So, from your very informed replies, my plan of action should be I think,
scrub the mould off the walls, ventilate the rooms (do I just drill some holes and buy a fitting?). Perhaps buy some of that insulation paint or a damp proof. The walls are very uneven, result or years of wallpapering and patching up. They are stripped back for the last number of years, but the whole room needs to be skimmed.

I dont think there is a leak or a rising damp problem (I may very well be wrong), and assue this is down to bad ventilation and insulation.

There is a water pipe running down outside the two affected rooms alright, which goes straight into the ground. Not sure where the water goes from there.

Wardrobes are all against the parity walls, so no sign of anything there. The external walls with the windows have no furniture against them now. The window and surrounds of the downstairs room are particulary bad, mould allover the widow sill and the blind is now caked in black dots.

Think I'll buy a dehuumidifier as well.

That box room is where my mother will start to sleep soon as she is unable for the stairs. Hence my desire to get it sorted. She has respiratory problems and I'm sure these would be worsened in a mouldy room.

What type of tradesman would be best to look at this for me? Is there a specialised trade that work on damp or ventilation issues or is it a standard engineer / builder.

I had a local builder in there last year to do another job and when I pointed out the mould, he never mentioned ventilation, merely slab and cover. So maybe I need more specialist examination.

Thanks again for your replies, I had spent several evenings trawling through the web reading up on damp problems, and like an illness, I'd probably end up self medicating and doing more damage by being ill informed.

Gareth2011

If you contact this crowd aaadamp.com the guy his name is ty ( I should have rapped instead of being unemployed ) If you tell him the details he will be able to tell you what maybe is the problem and how or if it can be fixed. I contacted him for a quote to get woodworm treated in my attic and he was so friendly on the phone and very helpful and cheapest quote i got from 3 companies. I don't know ty personally or have never met him before (still trying to get money together for woodworm treatment) all that I know is from speaking to him and the testimonials on his website we cant all be wrong :)

BryanF

• insulation paint : no such thing- there are no half-ass'd solutions
• what is the external ground level outside in relation to the internal floor area floor level outside?
• consider externally insulating the front wall
• check the water pipe, that could be a cause, but it does sound like poor ventilation
• window vents might be your easiest option, also open the windows more especially when sleeping
• dehumidifier is only a remedial option to dry-out the house, you need solutions!
• your mother has a respiratory problem, stop messing about with insulation paint, and think carefully about your ventilation strategy (maybe a demand controlled ventilation system with RH and CO sensor), get a damp specialist in to confirm the causes of mould!!! ad then externally insulate the walls
• forget tradesman: you need an architect/building surveyor that is used to dealing with such issues
• don't 'slab and cover' that's hiding the problem allowing mould to form behind the internal insulation and is not good for anyone especially you mum, with respiratory problems! did you read Mick's link to J.Little's studies on dry-lining..

PeteHeat

1940's was a good time for mass concrete houses, most that I know of had the vents built in.

Take a look at the walls outside there may be vents installed already, it is not unusual to find the vents were covered over inside the room.

.

Gareth2011

PeteHeat wrote: »

1940's was a good time for mass concrete houses, most that I know of had the vents built in.

Take a look at the walls outside there may be vents installed already, it is not unusual to find the vents were covered over inside the room.

.

My house has the vents at the front of the house too just below the floor level so air can get in around where there is wooden floors. Makes the floors freezing tho :mad:

PeteHeat

Gareth2011 wrote: »

My house has the vents at the front of the house too just below the floor level so air can get in around where there is wooden floors. Makes the floors freezing tho :mad:

Hi,

It is very important to keep those vents clear, without them your floors and joists can be completely rotted away in less than five years.

There are ways of insulating the floors but they are usually big jobs as the floor boards have to be taken up to do it properly.

The old answer to the cold draughty floors was to use newspaper under the floor covering such as carpet lino etc, it worked very well.

.

Gareth2011

Well pete,

Yeah I found this insulation roll out stuff you can put on top of floor http://www.theinsulationstore.ie/product-details.php?ID=10 .Il prob but underlay and carpet or wooden floor on top of that then.

whizbang

very often houses of this era had only poured concrete 'ring beam' around the top of ground floor and first floor levels. so a quick poke thro the wall at this level would seem to show solid all over. makes it easy to cut a vent under this beam.

Im joining the ventilation camp here by the way..:D

etn

Hi Folks. I am wondering if a pensioner lives in a Mobile Home, permanently,,, do they qualify? I would appreciate any info on this please. Cheers

BryanF

no