Insulation·rigid polyurethane 70mm
rigid polyurethane · 70mm
R 3.04
U 0.311 W/m²·K

rigid polyurethane, 70 mm — R 3.04

70 mm divided by a conductivity of 0.023 gives an R-value of 3.04. The U-value is 0.311, so a square metre leaks 6.22 W across a 20-degree difference.

Standards it meets

Not up to any of them yet

Material
rigid polyurethane
Thickness
70 mm
Thermal conductivity
0.023 W/m·K
Thermal resistance
3.04 m²·K/W
U-value
0.311 W/m²·K
Heat lost per square metre
6.22 W
As concrete
4.87 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 panel21 mm
  • phenolic foam61 mm
  • extruded polystyrene85 mm
  • graphite EPS94 mm
  • white EPS110 mm
  • glass wool113 mm
  • mineral wool122 mm
  • cellulose128 mm
  • timber396 mm
  • plasterboard548 mm
  • concrete4870 mm

Nearby cells

rigid polyurethane 50mm
R 2.17
rigid polyurethane 100mm
R 4.35
phenolic foam 70mm
R 3.5
extruded polystyrene 70mm
R 2.5

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 70mm
R 10
phenolic foam 70mm
R 3.5
rigid polyurethane 70mm
R 3.04
extruded polystyrene 70mm
R 2.5
graphite EPS 70mm
R 2.26
white EPS 70mm
R 1.94
glass wool 70mm
R 1.89
mineral wool 70mm
R 1.75
cellulose 70mm
R 1.67
timber 70mm
R 0.54
plasterboard 70mm
R 0.39
concrete 70mm
R 0.04

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 70 mm of rigid polyurethane?

3.04 — 70 mm in metres divided by a conductivity of 0.023.

Q. And the U-value?

0.311. That is 3.21 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 6.22 W across 20 degrees.

Q. How much concrete would match it?

4.87 metres.

Q. Which standards does it meet?

At 0.311 it does not clear any of them yet.