A good video on youtube about how to insulate a floor.
( Poser un plancher isolant thermique)
Website to calculate how much 100mm flooring I need.
Shopping list
The price here comes in at about 50 euro/m sq = 3150 euro
Alternative cheaper product
Recticel
Bricodepot.fr
This is Recticel FitForAll and here it’s sold in 30mm and 60mm sheets. But they are available up to 100mm (30mm, 40mm, 60mm, 82mm & 100mm) according to the Recticel Site
Lambda 0.023
This would result in a cost of 945 Euros for 7m x 9m (15 euro TTC / m sq) 60mm sheets
From the following site, 100mm sheets are available for 28 euro / m sq (= 1764 euro for 7m x 9m)
https://thyez.entrepot-du-bricolage.fr/pr-dalle-isolante-polyurethane-fitforall-120×60-cm-epaisseur-100-mm-recticel-matc09-963844,31224,29,444.htm
Celotex
GA4090 ( 1 304,52 € for 69.12m sq ) 90mm sheets
Lambda 0.022 Watts per mK
R value 4.05
http://www.isolation-pas-cher.com/catalog/category/view/s/isolation-plancher/id/17/?cat=135
Wood Fiber General
Not too good really, 4cm
James
R value 1.05
Wood Fiber Pavaflex Confort
Conductivité thermique : 0,038 W/(mK)
100 mm : R = 2,60 m².K/W
180 mm : R = 4,70 m².K/W
200 mm : R = 5,25 m².K/W
materiaux-naturels.fr
180mm boards are 18.75 Euro/m sq = 1181 euro for 63 m sq
Video on installing floor insulation
Under screed (on slab) possability.
This EPS is much cheaper than more promoted branded stuff and probably just as good. Here is a company in POLAND
https://www.matbay.fr/eps-
For
Another good video on how to insulate the floor below. Has key details of where to put a vapour barrier – GRADE -> Gravel (with drainage) -> EPS foam -> Vapour barrier (also holds the foam down before 4″ of concrete is poured – > Concrete
Good video on insulation below slab from Kingspan
https://www.youtube.com/watch?v=-sc8y073RUc
Thin sand blinding to level ->appropriate damp proof membrane (well lapped and folded), should lap high enough to connect with, or form, the wall damp proof course -> eps at least 2cm thick vertical around perimeter, top should be level with top of the floor screed (damp proof course), layer and overlap eps -> overlap eps boards with polythene sheet (as a vapour control layer), make sure polythene sheet has 150 mm overlap
PDF details
https://www.barbourproductsearch.info/Kooltherm%20K103%202nd%20Issue%20Aug%2016-file071371.pdf