Damp (of the coming through the house walls persuasion)

On one wall of our house, there is evidence of damp coming through. In my inexperience I have a couple of theories about its cause.

One is the a broken down pipe cause water to soak into the wall. Possible I guess.

However, with all the rain we've had lately, I've noticed puddles that form on my block paved drive, run right up against the wall where damp is getting in. In fact the last piece of floor to dry after rain is right up against the bottom of the wall. Yesterday I noticed a puddle at the bottom, and a damp patch running up the outside of the wall starting from the puddle, as though the wall is wicking the water up.

The block paving goes right up flush to the wall. I don't think it should. I'm fairly sure when I've seen other drives like mine there has always been about 4 inches of gap between the drive and the house walls, filled with gravel.

Does any of this make sense? Is there something I should be looking into doing.

 

Is the block paving above the DPC level? Or very near.
Even so it should not penetrate to the inside unless the cavity is blocked.

 

If like me you take a cheap Boriscope and drill a hole into the cavity, you may find that the cavity has been breached by that well known danger of the builder. They tend to let a lot of muck drop into the cavity when building the wall up. If the ties or a brick has dropped then you can find it will breach the gap.
I even found a brick bolster in thereto which I just had to let a friend in the trade know as he called me a fibber, due to him never losing tools.
Seems we all have lost them, now where did I leave that boriscope too.

 

I found a very large cold chisel in mine when I cut the wall out some years ago, when installing patio doors.

 

Worked on the Whitbread stately home once, the masons had managed to drop a lump hammer down 6 of the chimneys there.

 

Ah well that's another thing. Its about 4 rows of bricks below the damp course, BUT, some bright spark bridged the damp course on that wall by repointed the wall, and cementing over it. I don't think that's the problem though, because the evidence of damp on the inside is all below the damp course.

 

You've probably seen this French drain I installed before, but this seemed like a good place to put it up again

 

That's the sort of thing I was thinking Zig. Did you have to cut away any of the floor or was the gap already there and you just needed to dig it out?

 

I used my breaker to cut the concrete out, it had been paved right upto the wall. This house didn't have a dpc so this was the best solution in this case.

The digging out was helped by "Milo"



Who also ate my earplugs.

The job was for a Mod on another forum. So it was "mods rates"

 

If I was to save my pennies to get this and The Great Crack sorted at the same time, how many pounds worth of pennies ought i save do you reckon?

 

Just had a look back, I charged £500 for that job inc materials, but probably would have charged a bit more if it was someone I didn't know.

You not fancy doing it yourself then?

 

I'd be willing to try if I had the tools, knew how to use them without chopping too many bits of myself off.

 

I used a diamond bladed angel grinder to get a neat edge, then just the breaker for the concrete underneath. You can hire both, but you'll have to blag it that you've got the ticket for a grinder.

Peforated land drain was about £40 but its not absolutely necessary.

 

If your dpc has been bridged by render or concrete then that will act as a sponge and will cause damp eventually. The render or Crete sucks moisture from the ground, and eventually seeps.

 

What's a 'breaker'?