Sand and cement screed?

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Yes include perimeter insulation, no you don’t need perimeter DPM. I don’t know how competent you are, it’s doable, but in my opinion at the hard end of the scale of all jobs. Probably depends on the size.
 
screeding is not a diy job , cant see why you didnt finish it with concrete.
 
No pics have appeared?

The FFL of the next room (dining room?) is your benchmark - how much lower is the top of the slab than the benchmark - ie the depth of the screed with allowance for the finished floor cover material?
Was a membrane laid before the slab was poured?
 
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You probably need to watch some YouTube videos or something. But basically ....

Clean the surface well of all debris, brush on some pva or sbr solution or neat cement.

The screed needs to be quite dry, the damp sand may be enough, otherwise it's just a bit of water to add. It needs to be mixed well, and that's difficult due to the dryness. The mixing is very important to get right. If you squeeze a handful, no water should come out, and the clump should stay together not crumble.

Use a straight edge to roughly level it, and tamp, then use the edge of a metal float to drag the surface level, then use a wooden or plastic float in a swirling and pressing motion to compact and smooth the surface.
 
I’ve done it exactly as per woody but thought you’re meant to finish with steel float to close it after poly float
 
23vc said:
Yes include perimeter insulation, no you don’t need perimeter DPM. I don’t know how competent you are, it’s doable, but in my opinion at the hard end of the scale of all jobs. Probably depends on the size.
Click to expand...
Definitely needs perimeter insulation? That'll mean there's a 25mm gap of floor which is just insulation
 
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^woody^ said:
The screed needs to be quite dry, the damp sand may be enough, otherwise it's just a bit of water to add.
Click to expand...
Several people have said it's not a DIY job
 
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teaboyjim said:
So is it definitely needs perimeter insulation? That will mean there will be a 25mm gap of floor which is just polystyrene? I've never seen a floor before which has got 25 mm of polystyrene and anything hard or sharp you put down on the floor is going to gouge the soft polystyrene out or if a cat or dog claw this part of the floor then it's going to dig holes in it.
Click to expand...
Are you not having skirting boards?
the floor covering covers it anyway
Whether you need perimeter insulation depends on how the wall is insulated, I just assumed you’d want to as the slab had it
 
23vc said:
Are you not having skirting boards?
Click to expand...
Yes that's true there will be skirting boards. Would screeds in new build houses have this 25mm polystyrene/insulation section as well?
 
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23vc said:
Yes include perimeter insulation, no you don’t need perimeter DPM. I don’t know how competent you are, it’s doable, but in my opinion at the hard end of the scale of all jobs. Probably depends on the size.
Click to expand...
What thickness should the insulation be around screed?
 
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You dont need insulation around the screed but you do need insulation around the slab perimeter.
Still dont know the depth of the potential screed?
Its best practice for the membrane to flop up the walls - it can be left a little high behind any skirting or cut level with the FFL.
 
D

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