Damp in built in wardrobe

[Al1234]

Hi All

After some help on this and whilst I have found a few threads on here they mostly deal with traditional fitted wardrobes. Mine are a bit unusual in that they are fitted through the exterior wall of the house and into the roofspace over the garage. From what I can tell they are original (1930's house) or at least have been there for a very long time - wooden beads on the plaster work, lath and plaster ceiling in the wardrobe, original skirting board etc.

We have been in the house since the beginning of summer however as winter has progressed the mould has build up in the top of the wardrobes, we have these in the two main bedrooms. There is also a small amount of damp towards the bottom on the back wall.

I have attached a picture to try and explain how the wardrobes fit. The previous owners have fitted kingspan insulation (shown in red) to the floor of the wardrobes and also to the exterior of the back wall.

So any suggestions, as I see it there are three possible actions, add more insulation, inside the wardrobe, ventilate the wardrobe but to and from where, or possibly adding some low level heating like a tube heater?

 

[foxhole]

Probably no insulation to roof void, so cold spot promoting condensation, needs ventilation.Is garage ventilated over ceiling?

 

[Al1234]

Hi, thanks for responding, I've done a bit of poking around in the loft and think that the problem might be part of a wider problem with poor ventilation in the loft area.

The loft has been well insulated, original insulation between joists and then 200mm over the top of that. There is however evidence of condensation dripping down onto the insulation from the roof felt. There doesn't appear to be any ventilation to the attic void, no sign of soffit vents or any other form of ventilation.

Could it be that moisture is forming on the felt and dripping down onto the ceiling of the wardrobe where there isn't anything to catch it?

It's very difficult to see but it looks like the older insulation blocks much of the gaps between the eaves.

 

[vinn]

"a small amount of damp to the back wall" - what back wall, the closet back wall or the house back wall?

Keep the closet free from clothes or chattels and remove the door(s).
Have trickle heat and ventilation in the bedroom 24/7.

If your diagram is accurate how come you dont have similar condensation on the sloping soffit of the main bedroom?

 

[Al1234]

hi Vinn

In relation to the back wall I was referring to the back wall of the wardrobe.

In relation to the ceiling of the bedroom I had assumed that damp wasn't a problem here as the room itself was heated and reasonably well ventilated.

I take the point about removing doors and drying the whole out, but that doesn't deal with the cause.

 

[Al1234]

I took the opportunity this morning to snap a picture of the outside with the little bit of snow on the roof. It clearly shows that there is a difference in temperature in the area of the wardrobes.

Also attached are pictures inside the wardrobes showing the problem. The problem is much more acute in one than the other, in that one you can see a silica jell pop which hasn't really done much.

 

[tony1851]

Low-wattage tube heater is the way to go.
It doesn't heat the space, but promotes air movement which reduces condensation risk.

 

[Al1234]

Giving serious thought whilst I have the opportunity, ie bedroom being completely redecorated, to stripping the wardrobe back completely. I have read about issues cased by insulating in front of the existing plaster finish where condensation and mould continue to form out of sight.

Is it a bad idea to strip off the existing plaster from the back, ceiling and side of the wardrobe and batten and insulate using celotex to insulate on the inside - surely this will reduce the cold spots on the surface?

I also plan to remove all the existing shelving and replace with a more open system, akin to an airing cupboard with battens rather than solid shelves.

Aware of the issues caused by external ventilation is it worth venting between the two wardrobes, so that opening the doors in one room encourages airflow through the wardrobes in the other?

Although I'm not averse to putting tube heaters in, I did mention it in my original post I want to avoid the ongoing cost of running heaters in there if it can be avoided.

 

[Al1234]

So I had a bit of a poke around on the garage attic side last night taking down some of the insulation and looking underneath. Obviously this has been an issue for some time as there are various stages of insulation attempts!

There is battens and kingspan on the back wall off the wardrobes, but given that this is on the outside I'm not convinced that its really doing anything. Hence why I'm tempted to take this down, strip this inside of the wardrobe and reinstall there.

Under the floor of the wardrobes there is some older loft insulation badly tacked to the underside. Given that the wardrobes have kingspan on the floor inside as well I think the floor is pretty well insulated!

Then there is the ceiling, the lath and plaster ceiling has no insulation at all. Given the rest of the insulation around it I can only see this as intensifying the cold spot on the ceiling.