levelling a damp concrete floor

[ultimatehandyman]

I need to level a damp concrete floor that will be eventually fitted with a product similar to Karndean/Amtico so the floor needs to be dry and dust free.

At the moment the floor is damp as there is no physical DPM below the concrete slab.

concrete-floor.jpg (61.78 KiB) Viewed 41113 times

I can't seem to find a self levelling compound that acts as a DPM and some screeds that I have looked at do not seem compatible with liquid DPM's
I was thinking of painting the floor with KA tanking slurry then applying t a self levelling screed over the top, but I have contacted the people that make KA tanking slurry and never received an answer from their contact form

I also thought about Asphalt but that would be a lot of hassle and would still need levelling afterwards.

Your suggestions please?

[Job and Knock]

I've often seen the commercial flooring lads coat the floor with a green damp-proofing compound, but I think it's only suitable for smooth concrete with no cracks in it and I doubt that it's a full membrane. The other thing I saw on a recent job was a mesh membrane called "Newton" onto which the flooring was applied. Had a quick look at their site and I think it was the 603 mesh. Anyway, may be worth a try

[cotswold builders]

You might find it here;

www.polycoteuk.com

DPM Primer, first then the self leveling screed.

[HMCFLOORING]

I've often seen the commercial flooring lads coat the floor with a green damp-proofing compound, but I think it's only suitable for smooth concrete with no cracks in it and I doubt that it's a full membrane. The other thing I saw on a recent job was a mesh membrane called "Newton" onto which the flooring was applied. Had a quick look at their site and I think it was the 603 mesh. Anyway, may be worth a try

Think you may be on about balls 131 primer that is used to help adhesion of the screed this would then be painted with balls f75 or f76 for the DPM.

What i would use is
131 primer
Stopgap green bag (self leveling screed)
F76 (epoxy DPM)

All from F ball's
http://www.f-ball.co.uk/contact.asp

[Wes]

A little important info from polycoteuk for their primer and applying the levelling compound afterwards. They also recommend grinding your concrete first before applying the primer. Looking at your picture, I'd say its has some sort of paint on the floor that's gonna need removing. Take a look at the bottom of the guidelines below as I think that'll be the key (excuse the pun) for applying the self levelling.

For best results – use the following
procedure: The first coat should be
allowed to cure for 24 hours before
applying a second coat of DPM Primer
if required, otherwise the surface is
ready to receive a suitable top coating
(Flortex EP/Flortex Professional/
Flortex Chemical Coat). Spiked shoes
may be worn to avoid disturbing the
wet coating.
If the DPM Primer is being used
underneath a screed or self level we
advise that you apply one coat of DPM
Primer to the surface and allow to cure
and then apply a second coat with kiln
dried sand broadcast into the wet
coating to create a key for the screed
or self level to adhere to.

[ultimatehandyman]

I looked into a few options for sorting the floor out and decided to coat the floor with KA tanking slurry ( I phoned their helpline to see if self levelling screed could be applied over the top of the tanking slurry and it could ).

I applied about half a tub of KA tanking slurry to the floor using an old broom, then before 24 hours elapsed I mixed and applied 6 tubs of screwfix's no nonsense floor levelling screed.

The floor is now dry and level but I wish I had bought a floor screed spiked roller to get rid of the air bubbles (screwfix's instructions did not mention this or I would of bought one) There are now a couple of small air bubbles on the surface but it is ten times better then it was before

[DTWCeramics]

Always roll a SLC unless it has aggreggate in it, you get a much smoother finish at the end of it.

[Patsy]

Here is a picture of the levelled floor, which is no longer damp-

floor.jpg (29.84 KiB) Viewed 40611 times

If anyone else is thinking of doing this it was £25 for the KA tanking slurry and about £70 for the self levelling compound

[Patsy]

Hi, this was very helpful, thanks.
Can I ask how it's holding up?
Thanks,
Pat