rising damp but dehumidifier not extracting water

G_M

CharlieRabbit01 wrote: »

Rising is what they called it. So far a trench has been dug to below the internal floor level and that's it, the guy is currently painting the windows.

The building is 1900ish(age) so I'm not sure if there even is a DPC or its just failed.

They can call it 'falling' if they want. Doesn't make it true!

They have dug a trench to lower the ground level. Why? Because the external ground level is too high. It is above the level of the floor level and damp proof course.

So the damp in the ground is penetrating sidewise through the wall (not rising up the wall from below - if that were true, reducing the ground level would not help. Introducing a dpc would).

There probobly is a dpc (slate?). But no, it has not failed. It is probobly working just fine. It is preventing any damp from rising up through the bricks from the ground below on which those bricks sit. But it is not, and cannot, prevent damp from penetrating the wall at a height above itself! That is not its job.

G_M

Ben_Ombrello wrote: »

Google xxxxx Dry!

[EMAIL="ben_hunter@live.co.uk"]xxxr@live.co.uk[/EMAIL]

Reported.

Touting for business. (in every post)

CharlieRabbit01

G_M wrote: »

They can call it 'falling' if they want. Doesn't make it true!

They have dug a trench to lower the ground level. Why? Because the external ground level is too high. It is above the level of the floor level and damp proof course.

So the damp in the ground is penetrating sidewise through the wall (not rising up the wall from below - if that were true, reducing the ground level would not help. Introducing a dpc would).

There probobly is a dpc (slate?). But no, it has not failed. It is probobly working just fine. It is preventing any damp from rising up through the bricks from the ground below on which those bricks sit. But it is not, and cannot, prevent damp from penetrating the wall at a height above itself! That is not its job.

Admittedly it does look like rising from the inside but I agree it is penetrating, as the border came up to about halfway between the floor and the window.

I can't see any slate in the ditch just the brick work.

Hoping to catch him today to ask about the dehumidifier.

G_M

CharlieRabbit01 wrote: »

Hoping to catch him today to ask about the dehumidifier.

In my (stone) house, from outside you can't see anything.

But if I lift a floorboard I can see slate between the stone at a height just above ground level. Like you I had some damp when I bought (and several dpc.s tried to sell me new dpc / injection into stone etc), but like you I dug a narow trench round the external wall half-filled with pebbles.

I would use google or talk to surveyors etc to check whether the bitumen paint is a good idea. The risk is that it simply seals damp into the wall but I may be wrong about this.

hbomb

CharlieRabbit01 wrote: »

Admittedly it does look like rising from the inside but I agree it is penetrating, as the border came up to about halfway between the floor and the window.

I can't see any slate in the ditch just the brick work.

Hoping to catch him today to ask about the dehumidifier.

Obvious question, but has the dehumidifier's humidistat been set low enough for it to actually start working, eg 30%-40%? If the dehumidifier was just plugged in and turned on, the humidistat is sometimes automatically set at 60%, so it won't work until it is adjusted lower.

And make sure the windows/doors are closed.

CharlieRabbit01

G_M wrote: »

In my (stone) house, from outside you can't see anything.

But if I lift a floorboard I can see slate between the stone at a height just above ground level. Like you I had some damp when I bought (and several dpc.s tried to sell me new dpc / injection into stone etc), but like you I dug a narow trench round the external wall half-filled with pebbles.

I would use google or talk to surveyors etc to check whether the bitumen paint is a good idea. The risk is that it simply seals damp into the wall but I may be wrong about this.

The guy doing the work has been instructed by the LL (no idea who he is) he said about the bitumen paint, but the company who originally quoted (instructed by LA) didn't mention it.

Since Saturday there has just been a big hole.

I have an inspection from LA this week so I'm also going to express my concerns to them.

hbomb wrote: »

Obvious question, but has the dehumidifier's humidistat been set low enough for it to actually start working, eg 30%-40%? If the dehumidifier was just plugged in and turned on, the humidistat is sometimes automatically set at 60%, so it won't work until it is adjusted lower.

And make sure the windows/doors are closed.

I tried to look for something like that earlier in the week, but I can't see any dials or switches, its just plugged in.

The window is a pain to open so we tend to leave it closed anyway, and i've been shutting the door both the trap the air and keep the cat out.

It's an industrial one from a hire company. A quick google reveals it best works between 0-35degrees C.