MOULD & CONDENSATION ISSUE

[grifter]

I've just wiped around the reveal which was covered in black mould spores and wet dripping from the top of the reveal. What could be the possible causes??? It's only this window. The bedroom next door which has the window at the front of the house we have no problems with.
I've previously resiliconed and months later it comes away in places and looks like in the pics. Could it just be that the window unit is shot as it is dripping inside every morning and water sits on the cill? Probably 25/30 years old l'm guessing. It's so annoying. The loft is well insulated between and across the joists and this is normal the warmest room in the house.

Any help appreciated.

 

[JohnD]

What are the sources of moisture in this room?

When and how is it ventilated?

 

[grifter]

What are the sources of moisture in this room?

When and how is it ventilated?

It's a bedroom, so can't think of any sources of moisture. Normally have to open the windows to ventilate.

 

[^woody^]

What could be the possible causes???

The occupants create the moisture to form the humidity to cause condensation which leads to mould.

Think about what moisture is being created and how it is being ventilated.

 

[crank39]

2 people will breathe out a pint of water overnight, also looks like there might be cold spots all around that window and the moisture air is being attracted to it, are the glass units covered in condensation as well?

 

[JohnD]

It's a bedroom, so can't think of any sources of moisture. Normally have to open the windows to ventilate.

Apart from the occupant breathing, the most common source is wet washing hung over radiators, followed by a humid nearby bathroom.

Less common are leaks from baths, drains, waterpipes (including radiator pipes, and loft pipes above), leaks around or above windows, spilling gutters and waterpipes.

Fishtanks are a rare source.

Since water vapour is lighter than air, and can penetrate floors and ceilings, the source might be in the room below.

You didn't actually answer my question about ventilation.

 

[DiyNutJob]

Warm air hitting very cold window will condense into water. It's likely the window isn't properly sealed externally, and exposing the interior panel of the window to exterior temperatures. Sealant/caulk for interior use are often food for mould. Try using the exterior variety. Wiping the mould is no use. They can only be killed with bleach or other chemicals.

Timber windows are not hollow. Exterior temperature can not reach the interior side. So, that's an alternative you can consider.

 

[Wayners]

Looking at the pictures I suspect water getting in at the ears on outer sill.
Clean off silicone outside.
Mask it all up. Bricks with duck tape and sill with masking.
£10 metal foam from B&Q building section not store area. Bargain that.
Push a mastic nozzle on end of foam gun. Might have to cut end off of nozzle a bit and hold on with one hand.
Puch right in around frame and sill then inject foam.
Need to come down side and all along bottom.
Cut back when dry.
Remove tape.
Run silicone around.

You can see damp in corners. That's causing mould as water will be all around the flat brick tops under sill.
I've sorted a few like that. Silicone against bricks on its own is poor at stopping driving rain