Damp in Victorian Terrace

[Ali246]

Hi
As a this is my first house I'm very new to all this but here goes..
We have a very damp wall at the back of our late victorian terrace to the extent that all the paint has flaked off, plaster is crumbling and we get lovely outcrops of white hairy mould! It is a single brick wall which has been plasterboarded with non-original floorboards in the interior, the DPC was checked in our survey and found to be okay. The exterior to this wall has been very poorly rendered with what I assume to be cement render that has cracked and blown in several places in which you can see green algae growing! A previously leaking gutter above this has now been fixed. After perusing the forum on this topic I am of the opinion that removing the render will be the best option and then mayber re-rendering with lime render? I had initially looked into some of the wall coatings firms but now think this is definitely not the way forwards. Would it also be a good idea to hire a dehumidifier to dry out the wall once the render is removed?
Thanks for all help

 

[Matt Green]

Hi
As a this is my first house I'm very new to all this but here goes..
We have a very damp wall at the back of our late victorian terrace to the extent that all the paint has flaked off, plaster is crumbling and we get lovely outcrops of white hairy mould! It is a single brick wall which has been plasterboarded with non-original floorboards in the interior, the DPC was checked in our survey and found to be okay. The exterior to this wall has been very poorly rendered with what I assume to be cement render that has cracked and blown in several places in which you can see green algae growing! A previously leaking gutter above this has now been fixed. After perusing the forum on this topic I am of the opinion that removing the render will be the best option and then mayber re-rendering with lime render? I had initially looked into some of the wall coatings firms but now think this is definitely not the way forwards. Would it also be a good idea to hire a dehumidifier to dry out the wall once the render is removed?
Thanks for all help

Your wall is drying out slowly. The 'white mould' is salt crystalisation left behind when water evaporates from the surface of the wall.

Getting rid of the render is probably not the worst of ideas. If it's single-skin i'd be inclined to line the internal side of the wall in some fashion (energy efficiency and lower condensation risk etc).


Matt

 

[DaveBrigg]

Just to add to what Matt has already said, if the gutter was leaking for a long time, then your wall will have become waterlogged. It will take some time to dry out, maybe months. The cement render (apart from where it is blown) will trap the moisture, leaving it with the internal plasterboard as the only way out. If the render is cracked then it won't be doing the job it was designed for, and is best removed. When the wall is dry, and the state of the brickwork is clear, you can decide what to do next.
The good news is that you've fixed the gutter, and summer is on its way (that's what the paper said anyway)