Insulation·extruded polystyrene 200mm
extruded polystyrene · 200mm
R 7.14
U 0.137 W/m²·K

extruded polystyrene, 200 mm — R 7.14

200 mm divided by a conductivity of 0.028 gives an R-value of 7.14. The U-value is 0.137, so a square metre leaks 2.73 W across a 20-degree difference.

Standards it meets

  • passive house 0.15
  • Korean central-region wall 0.17
  • loose standard 0.30
Material
extruded polystyrene
Thickness
200 mm
Thermal conductivity
0.028 W/m·K
Thermal resistance
7.14 m²·K/W
U-value
0.137 W/m²·K
Heat lost per square metre
2.73 W
As concrete
11.43 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 panel50 mm
  • phenolic foam143 mm
  • rigid polyurethane164 mm
  • graphite EPS221 mm
  • white EPS257 mm
  • glass wool264 mm
  • mineral wool286 mm
  • cellulose300 mm
  • timber929 mm
  • plasterboard1286 mm
  • concrete11429 mm

Nearby cells

extruded polystyrene 150mm
R 5.36
extruded polystyrene 250mm
R 8.93
rigid polyurethane 200mm
R 8.7
graphite EPS 200mm
R 6.45

Same material, other thicknesses

extruded polystyrene 10mm
R 0.36
extruded polystyrene 20mm
R 0.71
extruded polystyrene 30mm
R 1.07
extruded polystyrene 50mm
R 1.79
extruded polystyrene 70mm
R 2.5
extruded polystyrene 100mm
R 3.57
extruded polystyrene 120mm
R 4.29
extruded polystyrene 150mm
R 5.36
extruded polystyrene 200mm
R 7.14
extruded polystyrene 250mm
R 8.93
extruded polystyrene 300mm
R 10.71
extruded polystyrene 400mm
R 14.29

Same thickness, other materials

vacuum panel 200mm
R 28.57
phenolic foam 200mm
R 10
rigid polyurethane 200mm
R 8.7
extruded polystyrene 200mm
R 7.14
graphite EPS 200mm
R 6.45
white EPS 200mm
R 5.56
glass wool 200mm
R 5.41
mineral wool 200mm
R 5
cellulose 200mm
R 4.76
timber 200mm
R 1.54
plasterboard 200mm
R 1.11
concrete 200mm
R 0.13

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 200 mm of extruded polystyrene?

7.14 — 200 mm in metres divided by a conductivity of 0.028.

Q. And the U-value?

0.137. That is 7.31 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 2.73 W across 20 degrees.

Q. How much concrete would match it?

11.43 metres.

Q. Which standards does it meet?

At 0.137 it clears 3 of them.