Condensation and blue/green and black mould

[Estrella]

Hi Folks,
My daughters bedroom with 2 external walls has condensation, but what is more worrying is that there is a large amount of furry mould growing where the two external walls meet.
To combat this the window is cracked open at 8am to 3.45pm, no wet towels or washing is left in this room. There is a chimney but it's blocked at the room end and is 6ft from the affected area at its nearest point.

The central heating is on in that room from 6am-8am and 3.45pm to 10pm daily.
The lounge directly below has a wood burner and it's chimney is in the same stack as the decommissioned one in daughters bedroom. There is no mould on the breast in either the lounge or bedroom. The lounge shares the same two external walls is dry as a bone.

My immediate thoughts is to wipe down the walls with neat bleach and stick a dehumidifier in there, but I really want to find the cause.

I am getting increasingly concerned about my daughters health now


Thanks


House info:
Late 1800's construction cottage - no cavity
Chimney in room - blocked at room end
Room carpeted and walls emulsioned, room is on the first floor
1 large (working radiator)
room dimensions approx 13'' square.
Loft above insulated

 

[KenGMac]

Several possibilities spring to mind,

What type of rainwater gutter is there? Old Cast iron? Possibly set on to the wall head? if so then the Cast may be punctured by rust making an easy path for rain water to access the wall head and into the Property?

If you can have a look @ the roof felt that is the under slating felt, if this has failed at the corner [or near to it ] and is allowing rain water to get "down the back" of the gutter [ the felt if failed can dump the rainwater not into the gutter but between the gutter and the wall, of wall head ] this also may be an ingress point for rain water.

If you can have a close inspection of the state of the masonry / Brick work joints in the immediate vicinity of the internal problem, there are sometimes areas of missing mortar that can allow water ingress.

One thing for sure there ain't no rising damp, unless you have a Video of it?

Is the roof void above, vented? and is there a vent in the vicinity of the problem area? Sometimes the roof vents if not sited correctly can induce "blank areas where no air is circulating = condensation on roof felt =run off into the room?

 

[^woody^]

Why has the mould been allowed to grow to this extent?

It does annoy me when I go to see properties with severe mould, as I always think "Hang on, mould does not grow overnight", but the occupant just moans about all the things which may have caused it except the main cause ... ie themselves ... and their failure to clean it up

I always ask "Why have you not cleaned this down sooner?" and 9/10 times I get a blank look as if it is just not something which they think they should be doing.

With regards to the timed heating pattern, then that is contributing as it is allowing air to cool and condense. There needs to be a more constant temperature maintained

This is typical condensation dampness and you need to follow the plethora of posts on dealing with condensation

 

[KenGMac]

Must admit I assumed that the mould growth was a very recent occurence hence I assumed that the problem was a form of penetrating dampness? who knows it may be.

As for wash down, use Bleach, but watered down 3 to 1

You could try getting a halogen type heater and aiming it at the offending corner, they will concentrate the heat at the problem area and it may go away?

 

[HERTS P&D]

Why has the mould been allowed to grow to this extent?

It does annoy me when I go to see properties with severe mould, as I always think "Hang on, mould does not grow overnight", but the occupant just moans about all the things which may have caused it except the main cause ... ie themselves ... and their failure to clean it up

I always ask "Why have you not cleaned this down sooner?" and 9/10 times I get a blank look as if it is just not something which they think they should be doing.

Woody you are bang on with what you say above, but the problem is when you point out that they haven't cleaned, you have sod all chance of getting the job as the customers will think that you have just insulted them!......................Dirty Dirty Dirty Customers.

Andy

 

[Estrella]

Why has the mould been allowed to grow to this extent?

It was behind a large picture / collage thing they have in their room. I don't know about you but I don't pull all my pictures off the wall every day to check for mould.

Thank you all for the helpful elements of your posts.