Damp patches on kitchen floor concrete

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Ive searched this topic in the forums, but all the hits seem to be very old .. so hoping there may be some updated information available. My house is estimated from around 1900 and has everything wrong with it, including quite a bit of movement. One of the endless list of issues is damp patches on the very uneven concrete kitchen floor (which is well below outside level and approx 1cm below level of adjoining hallway). Ive dug out the part of the floor which had the biggest damp patch, and found only wet compacted earth (no puddles), under the sand/DPM/1.5 inch concrete/thin screed. I didnt find any pipework etc. Im then assuming that the DPM under the concrete has failed where the damp patches are, so wondering if I can simply lay another DPM on top of current concrete (after filling in my hole) and screeding on top of that? Or do i need to dig out concrete of whole floor (4.5x4m) and start again?
Or indeed am i missing the obvious in my search for pipework possibly?
Probably not helping with the damp ground is the external concrete path which almost abuts the rendered house walls, with just a small gap (1mm) between the two along most of the house walls. I was thinking to fill these gaps with concrete or caulk. Would that be the correct thing to do I wonder?..
And i was also considering a chemical injected DPM - to cover all angles. Would it be worth it?
The structural surveyor suggested I spend as little as possible in making the house liveable for the 5 years I anticipated staying here .. as its not going to be an easy place to sell, when the time comes. So this is also a consideration. Any guidance would be hugely appreciated.
 
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99.9% of ground floor damp issues are resolved by lowering the ground around the house so it's 6 inches minimum below the inside floor level. If it was mine, I would have the floors dug out, 1 inch sand, 1200g dpm, minimum100mm kingspan with minimum 25mm kingspan upstand to outside walls, 1200g dpm again, and then 4 inch concrete.

Or, 1 inch sand, 1200g dpm, 4 inch concrete, minimum 100mm kingspan with minimum 25mm kingspan upstand to outside walls, 1200g dpm again, clip underfloor heating pipes down, and then 75mm underfloor heating screed.

If things are on the move, you may want to consider underpinning the walls first.

But your first move should be, get that ground outside lowered.
 
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OP,
why not post pics of the kitchen exterior walls, and the interior floor?
Are the kitchen walls showing damp stains?
 
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Thanks everyone. The idea of taking the outside level below inside level is pretty much impossible around the whole house, though I will be doing something with the patio area to drop it and put drains in .. as you can see from the picture, the patio door (dining room) is approx 30cm below outside, and the floor of the dining area is another 10+cm .. The large garden slopes to the house.
As for damp, its not showing via mould etc on the walls, though they all have the membrane between brick and plaster, which has surely helped. The other tricky thing to determine damp is that there would have not really been any heating on throughout the house for probably 4-5 years ..
Just another thought .. the structural surveyor suggested doing as little construction work around the house as poss, to reduce the risk of further movement. Plus I really really need to keep the costs down as Im already at double my budget and barely have a shell of a house.
Hopefully the pictures show the current situation more clearly.
 

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Thanks for the pics: they show that you have quite a bit of work needed on the house - a lot of work; an expensive amount of remedial building work.
If the garden slopes down to the house then presumably that ground is higher than the house, & you are getting ground water pressure.
Theres a massive amount of info and pics you would need to provide to get help from a DIY site like diynot.
I could take you thro it if you want but you would have to stay the course & provide all thats asked for - its a lot to ask of you as a DIY'er, & most of those who have tried to diy a large job eventually give up & bite the bullet for builders to carry on and finish the work?

What does "further movement" mean?
 
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And i was also considering a chemical injected DPM - to cover all angles. Would it be worth it?
no. it will not repair the leak nor change the ground level.

you can dig a french drain beside the wall, but at the age of your house it is to be expected that the drains and water pipes are leaking.
 
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Id be eternally grateful for any guidance and advice .. more than happy to provide pics/descriptions etc. I am getting building trade in for sure, but they each have their own ideas (which often contradict) and I having had to deal with a couple of nightmare builders so far, I need to be a lot more proactive than at the beginning of this 'project'. Plus any demolition or preparation work I can do myself should save a few pennies while im waiting for any trade to actually be able to start their work.
All plumbing renewed -first fix now done. The only bit that isnt due to be renewed is the mains pipework from the meter to the house ..
 
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So just going back to my original post and taking into consideration that lowering the outside ground is not a possibility... any thoughts on what would be the benefit (besides opportunity to add insulation) of digging down, laying dpm then thick layer of concrete and screed on that, versus just laying DPM on top of current concrete, and covering that with a thinner layer of concrete and then screed? Or another option seems to be to coat in liquid membrane?
I see myself as being in the property for 5 years and then trying to sell it on as Im fast falling out of love with the place. :).
 

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