Stowell Concrete Logo
Stowell Concrete Logo

Stowlite medium dense blocks/bricks 10.4N/mm² to BS EN 771-3

Products / Stowlite medium dense blocks/bricks 10.4N/mm²
Stowlite 10.4N/mm2 blocks are approximately 22% lighter than the dense block of the same strength and provide a good background for rendering.

All products available ex works. Prices on application. Please contact the sales office for further information and a quotation. For information on packaging click here.
Medium Dense Blocks ~ 10.4N/mm² (OVEN-DRY DENSITY approx 1600 kg/m³)
Size mm nominal (L x W x H) approx weight kg no. per tonne multiples of no. per pack
440x100x215† 15.5 64 44 88
440x140x215† 22.0• 46 32 64
† Also manufactured in close texture. Click here for photos and further information.
• Blocks in excess of 20kg – please use with caution after assessing the risks.
Coursing Bricks ~ 10.4N/mm² (OVEN-DRY DENSITY approx 1600 kg/m³)
Size mm nominal (L x W x H) approx weight kg no. per tonne no. per pack
215x100x65 2.3 430 452
215x140x65 3.2 310 296
Download UKCA Declaration
THERMAL CONDUCTIVITY: λ*
0.71 W/mK @ 3% m/c (Inside skin)
0.76 W/mK @ 5% m/c (Outside skin)
THERMAL RESISTANCE:
SIZE mm m²K/W at: m²K/W at:
100mm 3% m/c 0.141 5% m/c 0.131
140mm 3% m/c 0.197 5% m/c 0.184
(m/c = moisture content)
WEIGHTED SOUND INSULATION Rw:**
44 dB (100mm single skin, 209kg/m²)
46 dB (140mm single skin, 275kg/m²)
FIRE RESISTANCE:***
100mm  2 hrs
140mm  3 hrs
* Calculated from oven dry density
** Calculated using mass law curve - BS8233 (with 2 skins of dense plaster each 25kg/m²) 
*** Calculated using table NA 3.2 BS EN 1996-1-2 : 2005 (unplastered separating load bearing single leaf walls)

U-Value 0.18

Stowlite medium dense blocks/bricks 10.4N/mm² to BS EN 771-3
Outside resistance 0.040
19mm sand/cement render (λ1.00) 0.019
100mm dense 7.3N/mm² (λ1.43) 0.070
50mm low emissivity cavity 0.640
50mm foil-faced partial fill PIR/PU board (λ0.022) 2.273
100mm Stowlite 10.4N/mm² (λ0.71) 0.141
15mm dabs 0.170
37.5mm phenolic insulation (λ0.018) 2.083
bonded to…
13mm plasterboard (λ0.21) 0.062
Inside resistance 0.130
Sum of resistances 5.628 m²K/W
Uncorrected U-value 0.178 W/m²K
Mortar correction 0.000
Air gap correction 0.002
Wall tie correction – Staifix HRT4-225 0.002
U-VALUE 0.182 W/m²K

U-Value 0.18

Stowlite medium dense blocks/bricks 10.4N/mm² to BS EN 771-3
Outside resistance 0.040
19mm sand/cement render (λ1.00) 0.019
100mm dense 7.3N/mm² (λ1.43) 0.070
170mm high performance mineral wool (λ0.032) 5.313
100mm Stowlite 10.4N/mm² (λ0.71) 0.141
13mm dense plaster (λ0.057) 0.023
Inside resitance 0.130
Sum of resistances 5.736 m²K/W
Uncorrected U-value 0.174 W/m²K
Mortar correction 0.000
Air gap correction 0.000
Wall tie correction – Ancon ST1-300 0.004
U-VALUE 0.178 W/m²K

U-Value 0.16

Stowlite medium dense blocks/bricks 10.4N/mm² to BS EN 771-3
Outside resistance 0.040
19mm sand/cement render (λ1.00) 0.019
100mm dense 7.3N/mm² (λ1.43) 0.070
50mm low emissivity cavity 0.640
100mm foil-faced partial fill PIR/PU board (λ0.018) 5.556
100mm Stowlite 10.4N/mm² (λ0.71) 0.141
13mm dense plaster (λ0.057) 0.023
Inside resistance 0.130
Sum of resistances 6.619 m²K/W
Uncorrected U-value 0.151 W/m²K
Mortar correction 0.000
Air gap correction 0.007
Wall tie correction – Staifix HRT4-225 0.005
U-VALUE 0.163 W/m²K
Share by: