vacuum panel · 250mm
R 35.71
U 0.028 W/m²·K
vacuum panel, 250 mm — R 35.71
250 mm divided by a conductivity of 0.007 gives an R-value of 35.71. The U-value is 0.028, so a square metre leaks 0.56 W across a 20-degree difference.
Standards it meets
- passive house 0.15
- Korean central-region wall 0.17
- loose standard 0.30
- Material
- vacuum panel
- Thickness
- 250 mm
- Thermal conductivity
- 0.007 W/m·K
- Thermal resistance
- 35.71 m²·K/W
- U-value
- 0.028 W/m²·K
- Heat lost per square metre
- 0.56 W
- As concrete
- 57.14 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.
- phenolic foam714 mm
- rigid polyurethane821 mm
- extruded polystyrene1000 mm
- graphite EPS1107 mm
- white EPS1286 mm
- glass wool1321 mm
- mineral wool1429 mm
- cellulose1500 mm
- timber4643 mm
- plasterboard6429 mm
- concrete57143 mm
Nearby cells
Same material, other thicknesses
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 250 mm of vacuum panel?
35.71 — 250 mm in metres divided by a conductivity of 0.007.
Q. And the U-value?
0.028. That is 35.88 — the resistance plus 0.17 of surface — turned upside down, and a square metre leaks 0.56 W across 20 degrees.
Q. How much concrete would match it?
57.14 metres.
Q. Which standards does it meet?
At 0.028 it clears 3 of them.