FTBs building survey found 'rising damp' in 1930s semi - likely causes and best next steps?

Lunielumps

@FreeBear the forum wont let me reply to your post RE the damp so i am replying here...

Unless putting together flat pack counts as DIY then i'm afraid i have no experience.

I spoke with the surveyor again and he said the reason he marked the bitumen DPC as failed was because it was visibly fragmented and brittle where visible between the bricks - does this not sound right to you?

If the damp and tide marks aren't due to a failed DPC or the CWI, are there any other reasons damp levels might be high enough to cause concern in this type of house? especially since tide marks were visible next to the bay...  if the cavity and dpc were working then there shouldn't be enough damp for it to be visible on internal walls?

Lunielumps

Slithery said:

Lunielumps said:

 they have identified "rising damp"

No, they haven't. That's just what they want you to think...

Thanks Slithery - appreciate the damp may not be "rising" and that some levels of moisture in the walls are to be expected, but where we can see tide marks on the walls around the bay window there's definitely some kind of damp causing trouble. We're going ahead with the house purchase, so besides ventilating and heating the house is there anything else we should do to deal with the damp around the bay, be that penetrating damp etc?

stuart45

Lunielumps said:

IamWood said:

Have you looked around in the area for the other similar houses. It might be a common issue for the properties at that time. I know my house (1930) has some cracks around the windows. I simply repointed them.

Thanks Iamwood, it looks like next door has done some repointing on the brickwork above their master bedroom window, and had the window replaced - if a lintel had been added to theirs would i be able to tell from the outside?

You should be able to see the metal lintel under the soldier course.

IamWood

stuart45 said:

Lunielumps said:

IamWood said:

Have you looked around in the area for the other similar houses. It might be a common issue for the properties at that time. I know my house (1930) has some cracks around the windows. I simply repointed them.

Thanks Iamwood, it looks like next door has done some repointing on the brickwork above their master bedroom window, and had the window replaced - if a lintel had been added to theirs would i be able to tell from the outside?

You should be able to see the metal lintel under the soldier course.

What I did before I made my purchase, I tended to visit the neighbourhood a few times. Sometimes I simply knocked on the doors of some neighbours to have a friendly chat. I found this is very informative.

FreeBear

Lunielumps said: I spoke with the surveyor again and he said the reason he marked the bitumen DPC as failed was because it was visibly fragmented and brittle where visible between the bricks - does this not sound right to you?

If the damp and tide marks aren't due to a failed DPC or the CWI, are there any other reasons damp levels might be high enough to cause concern in this type of house? especially since tide marks were visible next to the bay...  if the cavity and dpc were working then there shouldn't be enough damp for it to be visible on internal walls?

Got a few patches along my DPC showing the same issue - This is more because the mortar is degraded rather than the DPC "failing". Without seeing some photos of these tide marks, I wouldn't like to say for sure what the issue is. But I'd be looking at leaking gutters & downpipes along with elevated ground levels against the walls.

I did have one problem area in my kitchen. Always prone to damp, and there was a drainpipe in that area outside. Even after fixing the drainage, damp was still a problem.. Took a few bricks out of the wall (just needed a pad saw to cut the mortar joints), and found the cavity full of building debris. No amount of chemical injection or other damp "cures" would have fixed the problem.. You might have debris in the cavity, and the only way to find out is to drill some small holes and insert an endoscope. But I'd look at the obvious culprits first.

stuart45

It's quite common to find debris in the cavity up to and above DPC level. At one time the lean mix fill below DPC was 150mm, but in modern times has been changed To 225mm. Working on the walls such as knocking out joints, or removing render has also been found to increase the debris by the vibrations knocking off some of the mortar snots on the inside of the walls and it falls down to the base of the cavity.

Lunielumps

Thanks very much for all the advice everyone! i can't currently share images or links to photos as i'm new to the forum, but by the time we move in and try some of the above fixes, if all else fails i will update with some pictures