Damp Issues in Victorian Ground Floor Flat with Cellar (London)

dstnhlms

Hi There, 

My wife and I are FTB and have gone through the classic rollercoaster ride of purchasing a home in London. After months of delays we were able to get the Level 3 Survey done and we have arrived at dreaded DAMP junction in our journey.

If anyone is up to having a look at this post and some of the pics to give us an understanding of the severity of the damp (difficult from just images, I know)

There are a few spots in the property that have damp.

1. Cellar Area
I believe most of the vents have been clogged for years and the cellar was filled with junk that might have been trapping moisture in. Also, there seems to be basement paint on the wall.
2. Bottom of front bay window
The wheelie bin area is on the other side of this and there looks like there is no air vents here either. Additionally the fireplace has been boarder up and wallpapered over...I'm guessing there is little to no airflow here so I'm sure that might be the biggest culprit. There also seems to be a constant wet spot about 50cm in diameter on the ground right on the other side of the wall where the damp is - is it possible that a constant drip from the roof/blocked drain is causing this?
3. Back wall of house (external side of wall open to paved garden)
The current owner has installed a layer of insulation on the outer brick by himself and it looks like there is a gap between the insulation and brickwork. I'm almost 90% sure that could be the cause at the back of the house

We have already begun the process educating ourselves heavily about the circa1905 build of brick and lime mortar. We would like to avoid an incorrect diagnosis and "band aid" solutions to the problem.

dstnhlms

Ah, I can't post images or links yet as I'm a newbie. Let me know if you're interested in seeing the pics and I can email them over, thanks 🙏

Doozergirl

I know we have no photos, but all of your suggestions sound like they're on exactly the right track.  

consumers_revenge

have a look at the nuaire drimaster or flatmaster. You will see them mentioned on here and I reckon I now have > less condensation and fresher air

dstnhlms

Thanks so much @Doozergirl and @consumers_revenge, I appreciate the info and encouragement. After doing massive amounts of reading we're feeling more confident about moving forward but obviously with a bit of negotiation with the seller. I've read a lot of articles from the seller's perspective and these "survey" outcomes seem do just do more harm than good in the end for both sides. 

I spoke to a lovely lady at Heritage House and she was shocked to hear that we had paid for a level 3 RICS survey in which the diagnosis was basically "there is damp, hire a damp proofing person to confirm this"

Once again, massively appreciated!