Finished Floor build up

Quack13

Below are the specs of my finished floor - to be put in next week.

I would be interested to hear what peoples opinions are on the make-up of this?

75mm Concrete Architectural Blinding on
150mm Insulation (Kingspan K3)
on 100mm 30N Concrete Slab with 1 layer A142 Mesh on
Radon Barrier on
50mm Sand Blinding
on 225mm Compacted Hardcore

I noticed on a pdf I downloaded from the easy screed site 'A-Rated Ground Floor' it mentions a 500 Gauge plastic membrane to be placed between the insulation and the screed.

Can anyone tell me what ths is exactly, is it expensive and is it something I would need to be putting in?

sinnerboy

Quack13 wrote: »

Below are the specs of my finished floor - to be put in next week.

I would be interested to hear what peoples opinions are on the make-up of this?

75mm Concrete Architectural Blinding on
150mm Insulation (Kingspan K3)
on 100mm 30N Concrete Slab with 1 layer A142 Mesh on
Radon Barrier on
50mm Sand Blinding
on 225mm Compacted Hardcore

I noticed on a pdf I downloaded from the easy screed site 'A-Rated Ground Floor' it mentions a 500 Gauge plastic membrane to be placed between the insulation and the screed.

Can anyone tell me what ths is exactly, is it expensive and is it something I would need to be putting in?

75mm Concrete Screed on
500 gauge polythene ( not expensive )
2 x 75mm Insulation (Kingspan K3)
on 150mm 30N Concrete Slab with 1 layer A142 Mesh on
Radon Barrier on
50mm Sand Blinding
on 300mm Compacted Hardcore

soldsold

Hi Sinnerboy,

Two questions if you dont mind:

1) Why 2 x 75mm kingspan instead of cheaper "bang for the buck" PS insulation?

2) Why 2 pours of concrete on the floor - if underfloor heating is not being used I had thought you could use only one concrete pour to save cost?

Thanks,

Steve

sinnerboy

soldsold wrote: »

Hi Sinnerboy,

Two questions if you dont mind:

1) Why 2 x 75mm kingspan instead of cheaper "bang for the buck" PS insulation?

2) Why 2 pours of concrete on the floor - if underfloor heating is not being used I had thought you could use only one concrete pour to save cost?

Thanks,

Steve

1. thick insulation boards can curl under screed . Better to stagger 2 thinner layers of insulation under

2. I assumed UFH . If not you are correct .

Quack13

sinnerboy wrote: »

75mm Concrete Screed on
500 gauge polythene ( not expensive )
2 x 75mm Insulation (Kingspan K3)
on 150mm 30N Concrete Slab with 1 layer A142 Mesh on
Radon Barrier on
50mm Sand Blinding
on 300mm Compacted Hardcore

Thanks for the feedback sinnerboy.

I have a couple of question re: the slight changes you suggested.

- what is the purpose of the polythene here
- whats advantage of having a 150mm concrete slab over a 100mm slab
- whats advantage of having 300mm compacted hardcore over 225mm
- is 75mm screed too much here? i have read elsewhere 50mm is optimum for UFH.

sinnerboy

to stop the wet screed attacking the foil faced insulation
min structural requirement
ditto
no . 50mm will crack and/or curl unless you use an "easy pour " screed ( google it )

about2build

Hi Sinnerboy,
Has there been any change to spec identified with regs 2011 or advancements?? Also what u value will that outlined give for floor?

good logs...

sinnerboy wrote: »

to stop the wet screed attacking the foil faced insulation
min structural requirement
ditto
no . 50mm will crack and/or curl unless you use an "easy pour " screed ( google it )

that foil peels away no matter what you do with it.