Screed thickness

[tedmosby]

Hi all,

I'm in the final stages of the buying process of a lower ground floor/garden flat (first time buyer so nervous times!).

Now as the flat evidently has damp, and I had a damp survey done with a local specialist. He confirmed that parts of the walls and flooring had damp in it and needed damp treatment, which was expected.

However, one important thing for me is very unclear: In the Damp specialist report it said that a layer of Screed with a thickness of 3-4 millimetre would be laid down, before a new wooden floor can be put in, with a drying time of just a few days.

However, every where on internet I seem to read that a layer of Screed needs to be 3 - 4 centimetre thick. This would have large implications on the time I could potentially move in (assuming 1mm per day of drying) and would also require more work I guess with making door post level etc.

I'm a bit confused and worried by this, so it would be super grateful if someone has some advice on this.

Thank you so much for any advice!
J

 

[dazlight]

I think he means a screeding compound. some people call a self leveller. Smoothing compound.

What it could need is some ardex DPM1c moisture suppressant as well.

 

[tedmosby]

Many thanks for your answer.

Yes, some moisture suppressant is also part of the damp proofing as far as I can read.

Would the 'screeding compound' at 3 - 4mm be sufficient, or do I still need some thicker screed laid?

Thank you!

 

[dazlight]

On the floor we always screed the floor at 3-5mm with ardex NA , then DPM1c up the wall a inch , then another coat of NA or ardex CL and keep that away from the bricks about a inch. Worked well for us over the years.

 

[tedmosby]

This was the official finding on the damp report:

"High moisture readings characteristic of rising and penetrating dampness has been found in the property. In the surveyor’s opinion, these readings are due to a failure and breakdown of the existing damp proof course and possibly the use of the wrong type of modern materials in an old property"

These were the steps laid out in the report to repair the damp issue

Walls:
1. Skirting Boards and Plaster Removal
2. Salt Neutraliser
3. Damp Proof Course Injection
4. Tanking Slurry
5. Waterproofing Render
6. Plaster Finish

Flooring:
1. The floor will be damp proofed with two layers of liquid DPM
2. A thin water proof concrete floor screed approximately 3mm deep will also be laid to provide a second layer of protection and to protect the liquid DPM.

Does this sound reasonable or troublesome?

 

[dazlight]

Sort of yeah. but they have to use the correct liquid Dpm.