Dripping walls, on the other side of air bricks

[chrissib]

Hi, I have wet walls in the bedroom, and I suspect it has something to do with air bricks. It is a bungalow, and after a recent persistant downpour, the gutter got blocked, causing water to run down the walls. I have 2 air bricks just above the dampcourse, and I suspect water has drained into these and soaked through, as the wall is dripping wet on the inside of these.

Can anyone suggest what to do. Do I block them up, try and clean them out, or maybe chisel the bricks out, reach in and clear the sh....er muck out?

Any assistance would be appreciated.

 

[JohnD]

fix the gutter problem, and let the wall dry out. It may take months. The more ventilation the better. Don't block air bricks.

If you think there is still water inside the cavity, drill a hole just above the DPC from the outside of the house and see what runs out.

It is very common for cavities to have lots of dropped mortar and other builders' rubbish at the bottom

Depending on age of house the cavity below DPC may be filled with concrete (for added strength)

 

[chrissib]

Thanks for the response. The gutter has been cleared, and water is draining through the downpipe and drain now.

The air bricks are sitting just above the damp course, so I think any water at that level, should have poured out through the holes.
Does the cavity drop down inside, after the air brick, or stay at the same level?

I have poked a long screwdriver through all of the holes, and there does not appear to be any blockages. I have opened the windows. A bit concerned how long it will take to dry out though. If we get another deluge, can't see it drying out in a hurry. Do I need to do anything else, on the inside maybe?

 

[JohnD]

you can buy or hire a dehumiodifier, if you want. It will make quite an impact in the short term, but the depth of the wall will still take months to dry out.

If using a dehumidifier, be aware that you need to close all the doors, windows and ventilators in the room you are drying (otherwise the machine is trying to dehumidify the world)

Remove any wallpaper (it will be damaged by damp and will probably push off with efflorescence, but it blocks evaporation anyway). If plaster is damaged, now is the time to knock it off

As you have a cavity wall, it should not matter that the outside leaf is damp. The cavity will prevent moisture getting to the inside wall (exceopt at the bottom where it might be full of dropped mortar and builders rubbish).