Help please. Big floor problem

[wooffy]

Posted a few days ago re a solution to my kitchen floor problem. Problem is I think I have a bigger problem than first envisaged. Was trying to level the floor of my kitchen through the hall to the front door as it was originaly a few different rooms and I wish to lay floor tiles.
Initially I thought this could be just a case of patch the low spots and then sling some self leveling over it. However after reading round the forum I decided to check the levels with a laser level and whilst at it I have a cheap damp detector so thought I'd test the concrete that was under the loose/hollow sections of screed.

This was mainly brought on by the musty earthy smell and this morning I noticed a slight amonia type smell as well. Well by the sounds the meter was making it doesn't look good. One section of a brick where there was originally a wall made the meter squeel like a pig and the majority of the other areas were I'd say by guaging the noise as medium damp.

What can i do with this floor? I'm assuming I need to rip up all the screed (which isn't damp just the concrete under it)

I took a datum level from where the front room meets the hall as a start point and measured the levels which I have sketched out using ms paint. (The grey lines represent approx meter squares to give an idea of scale)

I also checked the levels of the exposed concrete which varies from -50mm to as shallow as -25mm from the datum point.

House is an ex authority house and was built in 1950s to 1960s era (can't be exactly certain)

Some pics of the kitchen floor and the levels on top of the screed.

This pic is to show the relation of the floor to the DPC

 

[mattysupra]

what a mess!

I would be considering digging the whole lot up, install dpm and insulation and mass fill back in with concrete.

Or

Scrap of all the loose top screed. Remove the bricks and refill with concrete. Fill in voids with deep fill screeding compound (acrylic etc) Then epoxy dpm upto the walls dpc. Then loads of smoothing compound to get level.


I would go for the first option tho, will be cheapest and easiest but possible the most messy.

 

[nest]

MESS!! But all is not lost.. I fixed one just like this about 3 weeks ago and the customer now has a beautiful Karndean floor!!

First we patched the top screed with a rapid repair mortar and troweled it off as neat as poss ( you could use sand/cement mix but dont water it too much you want it to dry hard)..

Then we used an epoxy DPM, Uzins a good one but F.Ball does one thats just as good.. Make sure you get enough and bear in mind it never goes quite as far as they say!! I like to put it on with a trowel and then over it with a paint roller tight to the walls and I sprinkle kiln dried sand on it while it's still wet just to give the SLC something to get hold of..
It will look like glass when it's set...
Before you screed Prime it well and let it dry with a undiluted PVA based primer..

We have done this on many jobs and have never had a problem and although the DPM is pricey I trust it totally..

Good luck with it!!

 

[wooffy]

Sorry I never did reply with what happened.

Well a friend is in the flooring buisness so he came round and sorted it for me. First off he used a grinder on the floor to remove and loose stuff and bitumen. This was attatched to the biggest hoover I've ever seen.

Next up he primed the floor and mixed up a couple of tins of two part epoxy damp proof membrane and coated the floor. As it was setting he scattered what looked like grit over the floor so the self leveling compound would stick.

Once that had set he mixed up a couple of buckets of self leveling and partially filled some of the deepest sections.

Next day involved me being mixing biatch for him. after priming the already poured sections he poured the compound (water based) and then went over it with a spikey roller to remove any air bubbles.

There was hardly any trowelling at all, just a bit in the corners to make sure it floated upto the edge.

All tiled now and what a pleasure it is to tile on a decent level surface