Insulation·white EPS 150mm
white EPS · 150mm
R 4.17
U 0.231 W/m²·K

white EPS, 150 mm — R 4.17

150 mm divided by a conductivity of 0.036 gives an R-value of 4.17. The U-value is 0.231, so a square metre leaks 4.61 W across a 20-degree difference.

Standards it meets

  • loose standard 0.30
Material
white EPS
Thickness
150 mm
Thermal conductivity
0.036 W/m·K
Thermal resistance
4.17 m²·K/W
U-value
0.231 W/m²·K
Heat lost per square metre
4.61 W
As concrete
6.67 m

Thickness for the same performance

This is the number that shows what insulation is worth. Matching 100 mm of XPS with concrete alone would take 5.7 metres of it. No one builds a wall like that — which is why a concrete building only gets warm once a thin layer of insulation is added.

  • vacuum panel29 mm
  • phenolic foam83 mm
  • rigid polyurethane96 mm
  • extruded polystyrene117 mm
  • graphite EPS129 mm
  • glass wool154 mm
  • mineral wool167 mm
  • cellulose175 mm
  • timber542 mm
  • plasterboard750 mm
  • concrete6667 mm

Nearby cells

white EPS 120mm
R 3.33
white EPS 200mm
R 5.56
graphite EPS 150mm
R 4.84
glass wool 150mm
R 4.05

Same material, other thicknesses

white EPS 10mm
R 0.28
white EPS 20mm
R 0.56
white EPS 30mm
R 0.83
white EPS 50mm
R 1.39
white EPS 70mm
R 1.94
white EPS 100mm
R 2.78
white EPS 120mm
R 3.33
white EPS 150mm
R 4.17
white EPS 200mm
R 5.56
white EPS 250mm
R 6.94
white EPS 300mm
R 8.33
white EPS 400mm
R 11.11

Same thickness, other materials

vacuum panel 150mm
R 21.43
phenolic foam 150mm
R 7.5
rigid polyurethane 150mm
R 6.52
extruded polystyrene 150mm
R 5.36
graphite EPS 150mm
R 4.84
white EPS 150mm
R 4.17
glass wool 150mm
R 4.05
mineral wool 150mm
R 3.75
cellulose 150mm
R 3.57
timber 150mm
R 1.15
plasterboard 150mm
R 0.83
concrete 150mm
R 0.09

How to read this

  • Thermal resistance is the thickness in metres divided by the conductivity. Bigger is better.
  • The U-value adds 0.17 of surface resistance and then flips the total. Smaller is better.
  • Resistances add across layers, so a whole wall is the sum of its parts.
  • Conductivity varies by product; the values here are typical for the material.

Frequently asked questions

Q. What is the R-value of 150 mm of white EPS?

4.17 — 150 mm in metres divided by a conductivity of 0.036.

Q. And the U-value?

0.231. That is 4.34 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 4.61 W across 20 degrees.

Q. How much concrete would match it?

6.67 metres.

Q. Which standards does it meet?

At 0.231 it clears 1 of them.