Damp wall and timber floors, surveyor report

[Alex H]

Hi all, first my apologies on my first post being a request for help and advise. I did use these forums a long time ago when we did our first house but I've misplaced that login and email.

I've just had some initial feedback from the building surveyor on a property we are trying to buy.

For background, it's a 1920 hollow concrete block (no cavity) with render to the outside. Semi detached house. Suspected no dpc.

The survey has thrown up a few things I knew about, but I'd not spotted the damp on the side wall and potential issue to the timber floor.

The floors are timber, vented at the front by a couple of air bricks.

The side wall of the property has a concrete path running alongside and one downpipe discharges onto this path. The path is above internal floor level.

Some of the floor boards against that wall have been replaced with board. Couple of square metre, around the down pipe.

That wall has some damp around the down pipe. Further along the wall is the chimney with back boiler (cowl fitted) with a floor vent. Boards here appear to be fine.

I'm thinking it's a combination of poor ventilation, the path being at around internal floor height or above, and having poor water management that's causing the issue here.

I think I can sort the water management a bit better, but if the external path is above floor height, how can I stop water migrating through the render and hollow concrete block?

Internally taking plaster away is fine as we have a full refurbishment to do. I'm a bit more worried about the timber floor. I think it's ventilation is poor, but I'm struggling to see how I improve it without some sort of snorkel type affair on the side wall.

I'm going to see if I can get a damp specialist in there to do some more investigation. Am I just opening myself up to some crazy quote?

Could I tank the wall from the inside, improve the water management outside, and improve floor ventilation, without the need for specialist dpc injection (on that matter can you inject hollow concrete block..)

I'd appreciate any useful feedback, or a good damp contact in Cornwall.

Thanks.

 

[flameport]

one downpipe discharges onto this path.

Fix that before anything else - could easily be the entire cause of the problems.

damp specialist in there to do some more investigation. Am I just opening myself up to some crazy quote?

Probably.

specialist dpc injection

Burning a stack of £20 notes next to the damp wall would be cheaper and more effective.

good damp contact in Cornwall.

No such thing in Cornwall or anywhere in the known universe.

 

[Tigercubrider]

I am not an expert but a French drain would probably help?
I.e. Remove a strip of path where it touches the house, excavate a narrow trench and fill with gravel so that it drains away. Presumably requires somewhere for the water to go but quite simple and cheap.

 

[Alex H]

Thank you flameport, this does seem to be what I'm reading.

To my mind, if I stop the water splashing against the render, get that downpipe away to a small soak away, chop away the internal plaster, vent the floor and repair anything suspect with rot in the floor ; I'm doing about the best job I can and I should not be considering burning 50 pound notes.

Tiger, I was considering cutting the concrete path and installing a lined filter drain along and away from the house. That's within my skill base too.

Thanks for the replies, the knee jerk reaction is to find a 'damp specialist' but I'm hoping I can solve this with some common sense.

 

[Alex H]

Can I treat the external render with anything (once it's drier) to minimise water ingress from splashing?

 

[John D v2.0]

Basically solid walls work by drying out quicker on average than they gain moisture.
The first step is to stop all sources of water as you've suggested, so pipe all drains away and check for splashing etc.
Then ensure all paths slope away.
Then look at evaporation, so dig out beside the wall or ideally lower the whole path to keep water from soaking through too high up and increase ventilation down there.
To me, chemical dpc could be part of the solution, if the water is unable to be balanced in terms of evaporation of all the water passing the original dpc (slate perhaps behind the render). But I'd address all the rest before that.
Regarding the floor, the same logic applies, so you need it to dry quicker than the damp gets into the dirt. You also need general air flow around any timber down there.
Good luck!

 

[Alex H]

Super, thank you for taking the time to respond. I'm less concerned than I was earlier, but I need to go have a closer look at the floor in that area.

 

[John D v2.0]

No problem, of course get some photos up!

 

[Alex H]

Best images I have to hand of the side path, down pipe and an internal photo.

 

[stuart45]

Looking at the first photo it looks like it may be possible to lower the level of the path.

 

[Alex H]

Probably, there is a retaining wall to the left so I'd not want to alter levels too much.

 

[stuart45]

The retaining wall shouldn't be a problem. You could have a dwarf wall along side the slabs and drop the path. Having an external ground level higher than your floor levels is a common cause of damp problems.
I've lowered the levels on a few properties over the years and the owners were really happy with the results.

 

[Alex H]

Thank you Stuart, sounds very sensible. I'll check on the utility situation too, in case anything would stop that. That will be a fun manual job as there is limited access.

 

[John D v2.0]

Screw fix sell some Titan (, their own make) breakers that are actually quite good value for a one off job.
When I did the same job behind our house I bought the hand held one, I think 6kg and it did the job well.
The only tricky part was disposal, I got a rubbish removal company to do it.

At the front I ended up with a slope as the pavement is significantly higher than the doc, so we put in a narrow flower bed and a slope on the drive.

 

[Alex H]

I'll hope it's just a thin layer of concrete.

I'm minded to remove the path entirely and not put it back (it's not a right of way).

Disposal will be fun as the biggest thing I can get to the front would be a transit style tipper.