Insulation·rigid polyurethane 300mm
rigid polyurethane · 300mm
R 13.04
U 0.076 W/m²·K

rigid polyurethane, 300 mm — R 13.04

300 mm divided by a conductivity of 0.023 gives an R-value of 13.04. The U-value is 0.076, so a square metre leaks 1.51 W across a 20-degree difference.

Standards it meets

  • passive house 0.15
  • Korean central-region wall 0.17
  • loose standard 0.30
Material
rigid polyurethane
Thickness
300 mm
Thermal conductivity
0.023 W/m·K
Thermal resistance
13.04 m²·K/W
U-value
0.076 W/m²·K
Heat lost per square metre
1.51 W
As concrete
20.87 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 panel91 mm
  • phenolic foam261 mm
  • extruded polystyrene365 mm
  • graphite EPS404 mm
  • white EPS470 mm
  • glass wool483 mm
  • mineral wool522 mm
  • cellulose548 mm
  • timber1696 mm
  • plasterboard2348 mm
  • concrete20870 mm

Nearby cells

rigid polyurethane 250mm
R 10.87
rigid polyurethane 400mm
R 17.39
phenolic foam 300mm
R 15
extruded polystyrene 300mm
R 10.71

Same material, other thicknesses

rigid polyurethane 10mm
R 0.43
rigid polyurethane 20mm
R 0.87
rigid polyurethane 30mm
R 1.3
rigid polyurethane 50mm
R 2.17
rigid polyurethane 70mm
R 3.04
rigid polyurethane 100mm
R 4.35
rigid polyurethane 120mm
R 5.22
rigid polyurethane 150mm
R 6.52
rigid polyurethane 200mm
R 8.7
rigid polyurethane 250mm
R 10.87
rigid polyurethane 300mm
R 13.04
rigid polyurethane 400mm
R 17.39

Same thickness, other materials

vacuum panel 300mm
R 42.86
phenolic foam 300mm
R 15
rigid polyurethane 300mm
R 13.04
extruded polystyrene 300mm
R 10.71
graphite EPS 300mm
R 9.68
white EPS 300mm
R 8.33
glass wool 300mm
R 8.11
mineral wool 300mm
R 7.5
cellulose 300mm
R 7.14
timber 300mm
R 2.31
plasterboard 300mm
R 1.67
concrete 300mm
R 0.19

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 300 mm of rigid polyurethane?

13.04 — 300 mm in metres divided by a conductivity of 0.023.

Q. And the U-value?

0.076. That is 13.21 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 1.51 W across 20 degrees.

Q. How much concrete would match it?

20.87 metres.

Q. Which standards does it meet?

At 0.076 it clears 3 of them.