Hi I need a floor for my bathroom which is an old extension 2.5m x 5m built onto the back of my house (ground floor). At present its concrete which I presume must have been the back yard's deck judging by the extreme fall on the floor which all falls towards where the old yard gully was.
Now this concrete is significantly lower (around 150mm in some places) than the wooden floor in the main part of my house so I would like to raise it to a similar height so I was thinking of laying it in this order:
Screed on top of the concrete to get a flat level base, DPM, 60mm Kingspan boards, Vapor barrier (not sure about this), 18mm Ply sheets, Grout & Tiles.
Now I've never done a floor this way before so could do with some help such as:
1) How thin could I put down the screed onto the concrete bearing in mind it's just going under a floating floor? Some places will need to be around 60mm but then others only 3 or 4mm!
2) If it's to thin for screed could I maybe use screed for the big dips then finish off with a leveling compound or something?
3) Have I got my plans for laying the different layers correct?
4) Is it ok to just lay the Ply sheets on top of the insulation or should they be screwed together with a flange underneath or something if I'm laying tiles on em?
(P.S I really don't want to dig down & smash out the old concrete floor as my single brick walls and Party Wall are basically build straight onto the concrete deck with no founds!!!
)
Now this concrete is significantly lower (around 150mm in some places) than the wooden floor in the main part of my house so I would like to raise it to a similar height so I was thinking of laying it in this order:
Screed on top of the concrete to get a flat level base, DPM, 60mm Kingspan boards, Vapor barrier (not sure about this), 18mm Ply sheets, Grout & Tiles.
Now I've never done a floor this way before so could do with some help such as:
1) How thin could I put down the screed onto the concrete bearing in mind it's just going under a floating floor? Some places will need to be around 60mm but then others only 3 or 4mm!
2) If it's to thin for screed could I maybe use screed for the big dips then finish off with a leveling compound or something?
3) Have I got my plans for laying the different layers correct?
4) Is it ok to just lay the Ply sheets on top of the insulation or should they be screwed together with a flange underneath or something if I'm laying tiles on em?
(P.S I really don't want to dig down & smash out the old concrete floor as my single brick walls and Party Wall are basically build straight onto the concrete deck with no founds!!!
)
