Can someone explain this please....

Boooourns

There's damp/mold patch on my childs bed and we can't find an explanation for it.
Hes still in nappies and the mattress itself is dry. There are no other signs of damp in the room except condensation on the windows in the morning.
I've included a picture if anyone can help us, the carpet underneath is dry.
A humidity reading is giving us 70% which is the average throughout the house.

knickerbocker

I would suspect that your son has been breathing in this area, would this be in the area where his head would be?

corsav6

Sweat and dribble would be your most likely cause I would imagine, going by the position.

Boooourns

knickerbocker wrote: »

I would suspect that your son has been breathing in this area, would this be in the area where his head would be?

Yeah that makes sense, I'll double check tomorrow.

MicktheMan

This

Boooourns wrote: »

There are no other signs of damp in the room except condensation on the windows in the morning.

and this

Boooourns wrote: »

A humidity reading is giving us 70% which is the average throughout the house.

suggests that there may be a ventilation issue in the house. Continuous 70% RH and higher in a house in winter is too high and can easily result in mould thriving.

Boooourns

MicktheMan wrote: »

This

and this


suggests that there may be a ventilation issue in the house. Continuous 70% RH and higher in a house in winter is too high and can easily result in mould thriving.

Any ideas on how to solve this? Just today I had to clean mold off the bathroom walls with bleach, the rest of the house is fine though. Bought a new dehumidifier tablet in woodies today for the bathroom.
We try and leave windows open but that's hard in the cold especially with 2 young kids.

moonshadow

It's all about ventilation, nothing else. I appreciate that at this time of the year it's difficult to dry clothes outside, conserve heat inside by keeping windows open. To ventilate when having baths , showers, cooking etc.
But that's what causes mould .

MicktheMan

Boooourns wrote: »

Any ideas on how to solve this? Just today I had to clean mold off the bathroom walls with bleach, the rest of the house is fine though. Bought a new dehumidifier tablet in woodies today for the bathroom.
We try and leave windows open but that's hard in the cold especially with 2 young kids.

Owner or tenant?
Dry clothes indoors on rads or clothes horse?
What ventilation is present (mech extractors, wall/window vents) and where?
House heated properly?

Some houses have mould because they are not adequately heated.
Some houses have mould because they are not adequately ventilated.
Some houses have mould because there is too much moisture being generated within the house.
Most houses have mould due to some combination of the above.

Boooourns

MicktheMan wrote: »

Owner or tenant?
Dry clothes indoors on rads or clothes horse?
What ventilation is present (mech extractors, wall/window vents) and where?
House heated properly?

Some houses have mould because they are not adequately heated.
Some houses have mould because they are not adequately ventilated.
Some houses have mould because there is too much moisture being generated within the house.
Most houses have mould due to some combination of the above.

Owner
Clothes on rads in winter
Only one vent in sitting room (bungalow) extractor fan over oven
House heated with gas, rads in every room and open fire. House is warmed up every day.

We try and open windows as much as possible but the only one stays open all the time is bathroom window.
The mould is only showing in the bathroom and has been for years, easy to clean off but the house humidity is 70%

MicktheMan

Boooourns wrote: »

Owner
Clothes on rads in winter
Only one vent in sitting room (bungalow) extractor fan over oven
House heated with gas, rads in every room and open fire. House is warmed up every day.

We try and open windows as much as possible but the only one stays open all the time is bathroom window.
The mould is only showing in the bathroom and has been for years, easy to clean off but the house humidity is 70%

70% is too high in winter. Period. You really need to upgrade your ventilation big time.
Consider:
Don't dry clothes on rads, get a clothes dryer.
Investigate a mechanical ventilation system such as Mechanical Extract Ventilation (MEV), Demand Controlled Ventilation, Mechanical Ventilation with Heat Recovery (MVHR). As you house is a bungalow these systems are relatively easily retrofitted with some thought going into design, layout etc.

Boooourns

MicktheMan wrote: »

70% is too high in winter. Period. You really need to upgrade your ventilation big time.
Consider:
Don't dry clothes on rads, get a clothes dryer.
Investigate a mechanical ventilation system such as Mechanical Extract Ventilation (MEV), Demand Controlled Ventilation, Mechanical Ventilation with Heat Recovery (MVHR). As you house is a bungalow these systems are relatively easily retrofitted with some thought going into design, layout etc.

Sounds like a big job and expensive?? , would a dehumidifier make much of a difference if placed in the centre of the house?

Boooourns

Also we have one of those balloons up the chimney which stop the draught, we'll be taking that down to light the fire, I'd imagine this will help as well?

MicktheMan

Boooourns wrote: »

Sounds like a big job and expensive?? , would a dehumidifier make much of a difference if placed in the centre of the house?

Depends on what you call expensive:) View it as an investment!
A simple mechanical extraction system (extracting from the wet rooms) wouldn't be that expensive but will make a big difference.

A dehumidifier may work for a while until you get tired of the noise and the expense of running it.

MicktheMan

Boooourns wrote: »

Also we have one of those balloons up the chimney which stop the draught, we'll be taking that down to light the fire, I'd imagine this will help as well?

Yes, both from the heat the fire throws out and the opening of the passive stack ventilator (i.e. the chimney)

richj

The issue is down to ventilation end of.

The cheapest way around it would be to get 4" passive vents installed in every room. This is something you could do your self if you're any way handy with a drill and a hammer!
This will make the rooms a little bit harder to heat but will result in a healthier living environment.

Boooourns

richj wrote: »

The issue is down to ventilation end of.

The cheapest way around it would be to get 4" passive vents installed in every room. This is something you could do your self if you're any way handy with a drill and a hammer!
This will make the rooms a little bit harder to heat but will result in a healthier living environment.

Something like this?

richj

Yep, exactly what you need.

All rooms should have one.

wandererz

I watched this video on youtube:
https://www.youtube.com/watch?v=Oj99RNY55Es

Then i purchased a dehumidifier on Monday night.
By Thursday night (3 days later), this is the amount of water extracted from the bedroom:

http://imgur.com/a/DlyO6

Astonishing.

BTW, i do have an air vent in the room and the room has been drylined as well. The air vents were drilled specifically,when the drylining was done.

Supercell

The problem is that humidity at this time of year is usually above 70% externally as well but cold air holds less water so keeping the house warm will lower humidity even if the exterior air is wet. We have a house built in 1982 with single leaf cavity blocks and have problems in winter even with vents in all the rooms. I've found that the best solution is to keep the house reasonably warm (16c or higher all the time and get as good insulation in the attic as possible. I did notice when some rooms were allowed go below 14c when not used during the day for example that the mould would start to come back.
I wish could afford it we would wrap the exterior and get some kind of ventilation system installed, but thats likely to be the guts of 30k I'd guess which we dont have, so heating it is.
Ours is a small bungalow (about 90sqm). Mick any idea ballpark what a MVHR system is likely to cost? (3 bed, one bathroom, living room and kitchen)

MicktheMan

Supercell wrote: »

Ours is a small bungalow (about 90sqm). Mick any idea ballpark what a MVHR system is likely to cost? (3 bed, one bathroom, living room and kitchen)

MVHR systems require a good level of airtightness in order for the HR bit to be beneficial. Mine cost 4.5k installed/commissioned in a 200 sqm house (7 years ago).
However, there are alternatives such as DCV (Demand Control Ventilation) which combined with your wall vents would also be quite effective but cost less than half that of a MVHR.

MicktheMan

wandererz wrote: »

Astonishing.

Not really when you consider a normal household (say 2 adults / 2 kids) can output between 12 and 18 litres of water per 24 hours from normal activities (breathing, cooking, washing etc).
You also have to remember that if the internal air has high humidity then so does the furniture, furnishings, doors, walls etc and these also have to dry out.

PeteFalk78

Anybody any experience of Moisture Absorbers?

http://www.homestoreandmore.ie/multiroom/moisture-absorber-granules/invt/900915