Black Mould on New Conservatory Plaster - Drain Moved.... Conservatories are a great all-round addition to any home. Find help, advice and information on all aspects of this area.

[beestonite]

Hi,

I've recently had a conservatory built. I've had a few problems since 'completion' but they have since been sorted.

One problem which has recently come up is black mould on the plaster on the line of the skirting board and slightly above it in a pattern. It's in an area of about 5cm2. The area in question has a drain which was relocated running underneath it and is in the corner of the conservatory, where it joins with the original building. The drain isn't a real concern as the floor is a wooden suspended floor and the new drain runs well under this and is encased in concrete well below the wooden floor.

The plaster looks wet occasionally. We did have a problem with the guttering, it wasn't suitable for the purpose. The drains from the bathroom were channeled into it leading to massive overflow problems and water pouring down the side of the wall, coincidentally where the damp is. The outside wall does look wet in places on the brickwork and the mortar. How long should this take to dry?

Any help appreciated, sorry for the vague description.

Thanks

Phil

[welsh brickie]

use neat bleach to remove the damp and use a dehumidifier to suck out the moisture it will take a few days to dry out. the cause could be mortar on a brick tie allowing moisture to bridge the cavity or insufficient airflow under the floor