ᐅ Floor screed insulation EPS 50mm with thermal conductivity class 035 or 031

Hello everyone,

I have to take care of the insulation under the screed myself on my build. According to my documents, I need a 50mm EPS insulation with a thermal conductivity of 0.035 W/(m·K).

I am currently considering the following products:

23 packs of Styrofoam EPS 035 100kPa 50mm (4.5m² (48ft²) per pack) at €25.60 per pack
or

23 packs of Extrapor 031 150kPa 50mm (4.5m² (48ft²) per pack) at €35.47 per pack.

Is the additional cost of about €230 worth it?

Best regards,
Elektriker

I would like to expand my question and ask whether an additional cost increase of about 70% is worth it if I choose a PUR insulation board with a thermal conductivity of 0.022 W/m·K?

Best regards

Whether it is worthwhile needs to be calculated. In other words, how much heat is lost downward in relation to the rest. If your floor is a weak point in your house, it can definitely be worth adding more insulation here.
I installed 13cm (5 inches) of rigid polyurethane insulation board with a thermal conductivity of 0.022 W/mK plus 2cm (0.8 inches) of rolled mineral wool with a thermal conductivity of 0.035 W/mK.