Floating Floor Advice Please

[Devonish]

Floating Floor.



I am going to lay a floating floor in the extension, but wanted to run how I am going to do it passed you guys to see if I have this right.



We have built off a concrete slab, so the surface of that slab is the current floor. As I understand it I have to cover the concrete with a membrane. (1200 Gauge, 300 Micron) The edges must come up the wall until it meets the DPC that sticks out into the room. It sticks out at about 40mm and is one brick in height above the concrete base. Then the DPM is bent down and taped to the Membrane.



The membrane will have to be joined, so it should be overlapped at about 300mm?



Should the joint be taped?



Sheets of 100mm insulation (2400 x 1200) will be placed on top of the membrane.



Should they be tight against the walls or should there be a gap?



Should the joints between the sheets be taped?



Flooring Grade chipboard 22mm (2400 x 600) will be placed on top.

Should the chipboard be tight against the walls or does it need room to expand slightly?



Should the joints be glued?



If so what type of adhesive is required?



One side of the boards are printed on (Manufacturers name etc) should this side be underneath?



I know there are several questions here but if anyone would care to give me some answers I'd be very grateful.

 

[endecotp]

Sheets of 100mm insulation (2400 x 1200) will be placed on top of the membrane.
Should they be tight against the walls or should there be a gap?

I think the edge of the chipboard need to be supported on wood, so you should have 100x50mm battens around the edge of the insulation.
No expansion gap required here.

Should the chipboard be tight against the walls or does it need room to expand slightly?

Definitely need an expansion gap. Hide it under the skirting board.

Should the joints be glued?

The joints in the chipboard? Yes.

Kingspan and/or celotex have documents specifically about this sort of floor construction, e.g.
http://www.kingspaninsulation.co.uk...22-97bb-5861799ab02a/Thermafloor-TF70-pdf.pdf

 

[^woody^]

No gaps, use PVA wood glue.

Boards go anyway up unless the writing days otherwise. The tongue determines this, with the longest piece being at the bottom.

We both seem to be confused with your comments about DPM and membrane. You will need a DPM if there is non there already. You don't need a membrane if there is a DPM.

 

[Devonish]

No gaps, use PVA wood glue.

Boards go anyway up unless the writing days otherwise. The tongue determines this, with the longest piece being at the bottom.

We both seem to be confused with your comments about DPM and membrane. You will need a DPM if there is non there already. You don't need a membrane if there is a DPM.

Thanks for the other advice. Here are pictures of the DPC, oh ok. I see what I have done.
Sorry for the confusion. (The old soldier in me has come out - Disruptive Pattern Material)

So the Damp Proof Membrane is the plastic sheeting that goes on the concrete and the Damp Proof Course is sticking out of the wall.
The edges must come up the wall until it meets the DPC that sticks out into the room. It sticks out at about 40mm and is one brick in height above the concrete base. Then the DPC is bent down and taped to the Membrane.

Is that correct? Sorry about the confusion.

 

[^woody^]

Haven't you put a DPM under the concrete slab already?

Also, you don't look too have enough depth there to install enough insulation to current b/regs

 

[Devonish]

No the concrete was poured directly onto the concrete hard standing. 100mm of Insulation is going down to bring the floor level up to match the house floor. As Building Controller requested.

Thanks for your help.