Damp fiberglass insulation during build

[Robsco1]

We're having a garage built with a cavity wall, window frames were left exposed when it rained, and now we have damp insulation in the walls below the window frames.

Clearly evident from the white salt coming out of the mortar a metre below the window opening (and not on any other walls, or away from the window frames), and darker vertical sections of mortar, only below the window frames.

I had a feel in the cavity and the fiberglass was damp to the touch as far down as I could reach - to the sides was still dry.

The walls don't have any ventilation/air bricks of any kind, so I'm worried how long this will take to dry out on its own.

 

Questions are:

 

1.  Should I let this air out completely before closing the cavities?  ie leave the windows out and make sure no more rain can get in.

2.  How long may this take?

3.  If anyone tells me this is normal and it'll dry out on its own, are they bending the truth slightly?  ie, would it take 6 months.

 

I'm currently using small timbers to help create some space between the fiberglass and the brick.

The builder has done a runner, so we just have the roof to get on - doors are going to take another 4-6 weeks anyway, so leaving the insulation out of the rafters for now, and waiting to seal the cavity is no problem.

Thanks,

Rob

Edited Tuesday at 11:49 by Robsco1

[SteamyTea]

I would think it would dry out naturally.

If there was 100g of water per m², which is quite a lot, then it will take 226 kJ/kg of energy to vaporise it.

That is 0.063 kWh.

So not much in the scheme of things really.

 

(As with all things science, it is not as simple as that, but a good enough first approximation)

Edited Tuesday at 15:51 by SteamyTea

[Robsco1]

Do love a good bit of science 

 

Yeah, it's evaporating fine while the cavity is still open, and extra air gaps created between the bricks, my concern was when it becomes a sealed cavity, and how the moisture would get out then.

Edited Wednesday at 18:45 by Robsco1

[SteamyTea]

Moisture will get though anything, don't worry about it.