Damp and dehumidifiers

[stockhausen]

My niece rents a basement flat; she has major problems with damp which causes mould on the skirting board on an outside wall, around the windows and sills and generally in the bathroom and kitchen. This damp and mould is ruining her clothes and shoes.

I have offered to buy her a domestic dehumidifier but would be interested in hearing anyone else's practical, personal experience with a dehumidifier. Specifically:

• how effective it is?
• for how long do you have it on every day?
  
• how much does it cost to run?
• how noisy is it (particularly at night)?
• do you leave it on when you are out at work?
  
• what make and model do you use / have you used?

TVM

 

[stockhausen]

Surely the problem needs to be addressed by the landlord? Mould can be very harmful to your health.

In theory, yes. However, persuading any landlord to do something to correct problems takes time, this issue will NOT be resolved easily and kicking up a fuss will likely result in a Section 21 Notice to vacate so that the landlord can move in some other unfortunate for a year.

She loves the flat and doesn't want to leave it - she just wants dry clothes and to be rid of the mould.

To be honest, I am only really interested in the dehumidifier question.

 

[stockhausen]

What is causing the mould?

Landlord can be responsible if there is some structural issue like leaky pipes, poor damp proofing etc...

Tenant can be responsible if it is due to lack of heating and ventilation (like opening the windows etc..).

If she's drying clothes inside the flat etc... then it is probably worthwhile getting one regardless of the mould, it generally isn't too healthy otherwise.

Damp is causing the problem. The bedroom window is ALWAYS covered in condensation, there is no extractor fan in the kitchen and the bathroom extractor fan switches off as soon as the light is switched off! She uses a washing machine and hangs clothes on a drier in the flat.

The landlord may well be responsibel but I suspect that the problem cannot easily be resolved in her basement flat.

I am not entirely convinced about the heating / ventilation issue; the damp is in the air, you can heat it up and it will still condense on a cold surface, you can swap the warm hot air with cold wet air from outside but you still have a "damp" problem. I do however accept that "ventilation" may reduce the development of mould.

 

[stockhausen]

Thanks, I will have a look at the UniBond Aero 360° E-Connect moisture absorber. £12 sounds like a bargain. I wonder how long the £3.17 refill tabs last in the real world?

Ventilation is always an issue; she lives in a basement flat and goes out to work every weekday for a long working day - leaving windows open is not entirely practical. One is always fighting a battle between warmth and ventilation in the UK.

 

[stockhausen]

OK, I am currently looking at the MeacoDry ‘ABC’ Range 12L Compressor Dehumidifier which costs £159.99 - for which I will pay (as a late or early Christmas present) although she is going to have to pay the running costs.
I may also try the UniBond Aero 360s for "selective" placement.

 

[stockhausen]

I know damp is causing the (mould) problem, they go hand in hand, I'm asking about the underlying problem - what is causing the damp (and in turn the mould)?

Namely is there a structural issue as mentioned in the previous post - it isn't necessarily the Landlord's problem otherwise.

I don't think that there is an underlying structural issue, other than the design and location of the basement flat and the fact that she breathes, washes and cooks.

I am not aware of any leaking pipes, drains, taps, etc. The absence of an extractor fan in the kitchen and the bathroom extractor fan switching off as soon as the light is switched off doesn't seem particularly clever but I have my doubts that either issue is going to be resolved any time soon by the landlord.

To be honest, she is not particularly "after" the landlord, just looking for a solution.

 

[stockhausen]

The £200 Meaco DD8L is a desiccant dehumidifier and can work well in lower temperatures.
The £160 MeacoDry "ABC" 12L Compressor Dehumidifier works best in temperatures above 20°C, it is clamied to be quieter and very economical to run.

I'm not quite sure how warm she keeps her flat (I will ask) or whether this info will help her decide but perhaps the Dehumidifier Buyer's Guide website (LINK) will help?

 

[stockhausen]

Looking at Which? reports (which I have done), I get the impression that passive units are next to useless - unfortunately.
Having said that, one may well be OK in a 2m x 2m outhouse?

 

[stockhausen]

Thanks for that; the FlatMaster (LINK) is a REALLY good idea, I will get her to put it to the Landlord - very many thanks!

 

[stockhausen]

Blimey - the Flatmaster costs over £300 - just for an extractor fan in reverse!

 

[stockhausen]

I appreciate you trying to help your niece but it must be said that in all my years I am yet to see more that a couple of genuinely dry basement flats - and I’ve seen many.

They just aren’t practical places to live unless the walls are tanked properly, a sump is in place and an active air flow system too - it is also vital to have proper kitchen and bathroom extraction and to completely adjust your lifestyle to suit the unfavourable living situation.
[SNIP]

I take your point here. However, your response is what I would describe as somewhat "Irish".

As a Junior Rep for a Pharma Company she is where she wants / needs to be. She has a private parking slot and convenient access to public transport. Finding ANY flat has not been an easy experience. She was asked to leave her previous (ground floor) flat because the Landlord was selling up - "Tenants can't be choosers"

Her Landlord is "stalling"; I have suggested that she contacts the Environmental Health Dep't of the local Council to get an "Improvement Order" imposed on the Landlord. Neither of us have any experience of doing this but suspect that dues to Government cuts and their sympathy towards Landlords, the Council will not help much if at all and that the Landlord will then give her "Notice to quit" and as you suggest, find the next victim.

I find that "It's easier to heat as well as you're not heating the damp air" is hard to believe, not the physics of heating high humidity vs low humidity, but the nature of blowing cold air into the place.

I am inclined to agree with this but I do recall talking to the owner of a basement flat some years ago who said that he had sorted out a damp and mould problem by mounting a small extractor fan "backwards" in an outside wall. I didn't pay much attention at the time since I thought the whole idea was counter-intuitive - and probably "silly" - I may have been wrong?

 

[stockhausen]

Tread carefully... This course of action would almost certainly result in a S21/NTQ at the Landlord's earliest opportunity as you suggest, as it is very confrontational!
. . .

Yes, I entirely understand the "issues".

However, the damp is a genuine problem, she noticed it as she moved in and immediately reported it to the Agent and the Landlord who didn't actually do much about it at the time - just stalled.

It is my understanding that "A Landlord cannot use a Section 21 notice if the council has served an improvement notice on the property in the last 6 months or has served a notice in the last 6 months that says it will do emergency works on the property." (LINK).

This (drastic and confrontational) course of action should give her some breathing space to find alternative accommodation, will also help any future tenant and in truth will also encourage the Landlord to behave sensibly. Sorry if that upsets you as a Landlord but "so it goes".

. . . Damp is 'usually' down to tenant lifestyle . . .

That is certainly a point of view but as has been pointed out earlier, basement flats are frequently plagued with damp; the problem can also be unsuitable buildings that really shouldn't require a Tenant, at their expense, to heat the (ventilated) house (and the local area) like a furnace.
. . .[/QUOTE]

Why not reach out to the landlord and ask them to visit if possible, run through the problem and see if they can advise on what the Tenant is doing wrong, and offer to assist with sorting a solution. As a Landlord we would rather have a good tenant in for a long time than ongoing chopping and changing.
. . .
Have a chat with the Landlord, you might find a good solution together.

Tried that, the Landlord, as I suggested, is prevaricating - possibly until six months have passed - perhaps they feel that in a market where ANY housing is in demand, they are prepared to have "churning"?

 

[stockhausen]

As I said, 'usually' . .

A couple of people have mentioned "drying clothes indoors" - other then relocating to a warmer, dryer climate I don't really know what the option is in the case of a basement flat with a tiny, exposed "yard" as opposed to a garden with a shelter and a rotating dryer?

I am not quite sure how a Thermometer / Hygrometer would help, the flat as a whole is demonstrably damp and suffers from mould - the living room probably suffers least but then it would, wouldn't it?

There is no extractor fan in the kitchen - CRAZY! The extractor fan in teh bathroom only stays on while the light is on - also somewhat crazy and as it happens, the wiring is probably illegal to boot.

I am not sure about the windows, I will ask her to have a look. Since she is out of the flat for much of the time and it is fairly "accessible" she may be reluctant to leave windows open, even if supposedly secure.

Please don't get me wrong, I am VERY grateful to you and other for any input / advice and I will certainly post as things progress.

I have said that I will organise a dehumidifier for her and will do so, it is just a question of which one . . . ? The choice seems to be around one of two Meaco units, either the £200 Meaco DD8L (desiccant dehumidifier) or the £160 MeacoDry "ABC" 12L (compressor dehumidifier) - they seem to get good Which? reports and customer recommendations. The dessicant unit is supposedly more appropriate / effective / suitable if the flat is below 15°C

Ask her if she ever opens the windows?
. . .

I will look into whether there are opening / lockable windows and whether she does / can leave them open while she is out. For what it is worth, my niece is certainly aware of the advisability of ventilation and air circulation.

 

[stockhausen]

I’m not entirely sure what you mean by ‘Irish’ . . .

It is a reference to a traveller asking someone for directions - the response was "Well I wouldn't start from here."

My niece is in the (unenviable) position she is, as I have described in some detail. I am looking for suggestions as to how best she can eliminate or significantly reduce the damp and the mould - she is reluctant to move again.

 

[stockhausen]

I ended up buying her a MeacoDry ABC 12 litre with a green top, energy efficient and super quiet - hope it works out!

 

[stockhausen]

Open your windows, especially this time of year and its free.

Whilst this would be an ideal solution I really can't see it as being practical where the flat is a ground floor flat and the occupants are out at work all day every weekday.

• Get up and shower
• Go to work at 08:00
  
• Get home from work at 19:00
  
• Cook and eat supper
• Possibly do some laundry which is inevitably going to be left indoors to dry
• Listen to music, watch a video or whatever
• Back to bed
• Rinse and repeat

Condensation is at best an inevitable consequence of humans going about their daily activity and putting vapour into the atmosphere which then condenses on cold surfaces. Ventilation will help where the outside air has a lower level of humidity than the indoor air.

 

[stockhausen]

As an update to this sorry tale, it seems that the Meaco dehumidifier has helped but not entirely resolved the problem of damp and mould. The warmer, dry weather can't come soon enough.

I recently saw a cheap dehumidifier in Aldi which quoted effectiveness based on an ambient temperature of 30°C and 80% relative humidity! Who on Earth uses a dehumidifier in a sauna?

 

[stockhausen]

Any idea whether one could use PIV (Positive Input Ventilation - LINK) to bring in air via the fan-light above a front door rather than from the loft space?

I realise that the loft space is effectively an area heated (and perhaps dried) via heat escaping from the house in general whereas random air from the open air may not work. In relation to that, would running an extractor fan in reverse in a bathroom work?

 

[stockhausen]

. . .
Ours [PIV system] is fed from the loft but could have been from outside so defi an option.

I have tried to do some on-line research on this and most references seem specifically to refer to feeding air from the loft space - which will typically be a few degrees warmer than the open air.

. . . however, see below. . .

Do you just get an electrician to fit one of these PIV systems? Do you need trickle vents installing as well, to allow the positive pressure to escape? . . .

I am not certain that an electrician needs, by law, to fit a PIV since it will typically feed into a hall rather than a kitchen, bathroom, etc.

HOWEVER - if you are not 100% confident about messing safely with 240 Volts - USE AN ELECTRICIAN!

As to trickle vents, the clue lies in the description, "Positive Input Ventilation".

Since the idea is to push humid air out of the house, some sort of "escape" route would seem to be essential:

Positive Input Ventilation or PIV Systems work by ensuring the movement of air from inside a property to outside from a unit. The PIV unit circulates fresh filtered air into the property at a continuous rate, encouraging movement of air and reducing excess moisture which can cause condensation and damp.

Positive Input Ventilation (PIV) systems help your whole home to breath and improve the indoor air quality by gently circulating fresh, filtered clean air into your property at a continuous rate.

Our range of Positive Input Ventilation (PIV) units help to reduce moisture trapped inside your home which if left unmanaged can cause condensation problems and lead to mould growth.