rigid polyurethane · 120mm
R 5.22
U 0.186 W/m²·K
rigid polyurethane, 120 mm — R 5.22
120 mm divided by a conductivity of 0.023 gives an R-value of 5.22. The U-value is 0.186, so a square metre leaks 3.71 W across a 20-degree difference.
Standards it meets
- loose standard 0.30
- Material
- rigid polyurethane
- Thickness
- 120 mm
- Thermal conductivity
- 0.023 W/m·K
- Thermal resistance
- 5.22 m²·K/W
- U-value
- 0.186 W/m²·K
- Heat lost per square metre
- 3.71 W
- As concrete
- 8.35 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 panel37 mm
- phenolic foam104 mm
- extruded polystyrene146 mm
- graphite EPS162 mm
- white EPS188 mm
- glass wool193 mm
- mineral wool209 mm
- cellulose219 mm
- timber678 mm
- plasterboard939 mm
- concrete8348 mm
Nearby cells
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
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 120 mm of rigid polyurethane?
5.22 — 120 mm in metres divided by a conductivity of 0.023.
Q. And the U-value?
0.186. That is 5.39 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 3.71 W across 20 degrees.
Q. How much concrete would match it?
8.35 metres.
Q. Which standards does it meet?
At 0.186 it clears 1 of them.