Stone wool (mineral wool) at 100 °C — heat-loss table

λ = 0.041 W/m·K at mean temperature ((100+20)/2 = 60 °C, from the published curve). Pipe losses per metre, four thicknesses, savings vs bare.

Pipe	30 mm W/m	50 mm W/m	80 mm W/m	100 mm W/m	BARE W/m	Surface @50 mm	Saving €/m·yr @50 mm	t CO2/m·yr
DN25	19	14	12	10	84	23 °C	€34	0.12
DN50	27	20	16	14	152	24 °C	€64	0.23
DN80	36	26	19	17	223	24 °C	€96	0.35
DN100	44	31	23	20	287	25 °C	€125	0.46
DN150	61	42	30	26	423	25 °C	€186	0.68
DN200	76	52	36	31	551	25 °C	€243	0.89
DN300	108	72	49	42	814	25 °C	€362	1.33

Assumptions: 20 °C ambient, still air (h=10 W/m²·K combined), €0.05/kWh fuel, 8000 h/yr, 82% efficiency, 0.183 kg CO2e/kWh (DESNZ 2024). Flat surfaces at this duty: bare 800 W/m² → 61 W/m² at 50 mm (≈€361/m²·yr saved). Method: ASTM C680 simplified — methodology. Your exact case: free calculator.

Context

All materials at 100 °C

Material	λ W/m·K	Loss W/m	Surface	Saving €/m·yr	t CO2/m·yr
Stone wool (mineral wool)	0.041	31	25 °C	€125	0.5
Glass wool	0.038	29	24 °C	€126	0.5
Ceramic fibre (RCF / AES blanket)	0.060	44	27 °C	€119	0.4
Aerogel blanket	0.023	18	23 °C	€131	0.5
Calcium silicate	0.056	42	26 °C	€120	0.4
Expanded perlite	0.061	45	27 °C	€118	0.4
Cellular glass	0.047	35	25 °C	€123	0.4
Microporous (fumed-silica) panels	0.022	17	23 °C	€132	0.5
Elastomeric foam (FEF)	0.040	30	24 °C	€125	0.5
PIR / PUR rigid foam	0.028	21	23 °C	€130	0.5
E-glass needle mat	0.045	34	25 °C	€124	0.5
Silica needle mat / fabric	0.055	41	26 °C	€120	0.4

DN100 pipe at 100 °C, 50 mm insulation, per metre of pipe; bare loss 287 W/m. λ at mean temperature; € and CO2 per metre·year at €0.05/kWh, 8000 h, 82% efficiency. Method: ASTM C680 simplified (h=10).

Material datasheet: Stone wool (mineral wool) → · temperature class: by temperature →

FAQ

Questions on this topic

How much heat does a pipe at 100 °C lose with stone wool (mineral wool)?

With 50 mm at 100 °C (λ=0.041 at mean): DN50 loses 20 W/m, DN100 31 W/m, DN200 52 W/m — vs 287 W/m bare for DN100. Full table on this page.

What surface temperature does stone wool (mineral wool) give at 100 °C?

≈25 °C with 50 mm on DN100 (20 °C ambient, still air). Personnel-protection targets (≤45–60 °C) may need more thickness — see the 80/100 mm columns.