Insulation·rigid polyurethane 250mm
rigid polyurethane · 250mm
R 10.87
U 0.091 W/m²·K

rigid polyurethane, 250 mm — R 10.87

250 mm divided by a conductivity of 0.023 gives an R-value of 10.87. The U-value is 0.091, so a square metre leaks 1.81 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
250 mm
Thermal conductivity
0.023 W/m·K
Thermal resistance
10.87 m²·K/W
U-value
0.091 W/m²·K
Heat lost per square metre
1.81 W
As concrete
17.39 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 panel76 mm
  • phenolic foam217 mm
  • extruded polystyrene304 mm
  • graphite EPS337 mm
  • white EPS391 mm
  • glass wool402 mm
  • mineral wool435 mm
  • cellulose457 mm
  • timber1413 mm
  • plasterboard1957 mm
  • concrete17391 mm

Nearby cells

rigid polyurethane 200mm
R 8.7
rigid polyurethane 300mm
R 13.04
phenolic foam 250mm
R 12.5
extruded polystyrene 250mm
R 8.93

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 250mm
R 35.71
phenolic foam 250mm
R 12.5
rigid polyurethane 250mm
R 10.87
extruded polystyrene 250mm
R 8.93
graphite EPS 250mm
R 8.06
white EPS 250mm
R 6.94
glass wool 250mm
R 6.76
mineral wool 250mm
R 6.25
cellulose 250mm
R 5.95
timber 250mm
R 1.92
plasterboard 250mm
R 1.39
concrete 250mm
R 0.16

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 250 mm of rigid polyurethane?

10.87 — 250 mm in metres divided by a conductivity of 0.023.

Q. And the U-value?

0.091. That is 11.04 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 1.81 W across 20 degrees.

Q. How much concrete would match it?

17.39 metres.

Q. Which standards does it meet?

At 0.091 it clears 3 of them.