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Thermal Insulation

 

The tables on the following pages detail the 'U' values you can achieve using 100mm Cellular blocks and Solid blocksand the 115mm Cellular blocks and a wide selection of partial or total cavity fill systems.

All values are based on a structure built in a normal exposure range, with an outer leaf of medium density brickwork and inner leaf finished with lightweight plaster.

All resistances used in these calculations are taken from the C.I.B.S. Guide A3.

For more information concerning "U" values/heat loss calculations, please contact our Technical Department on 01952 586778.

As insulation manufacturers may change their specifications it is advisable to check with them that the specification shown in the tables following are still current.
Besblock Pumice blocks U-value guide table
All U-values calculated in accordance with BS EN ISO 6946
All U-values based on 12.5mm plasterboard applied by dabs method

 

Partial Fill Cavity Insulation

  
 
"U-values attained W/m2K"
 
90mm
100mm
100mm
115mm
140mm
Insulation manufacturer & details
Insulation 
Thickness
(mm)
Solid
Cellular
Solid
Solid
Solid
Celotex Limited
Telephone 01473 822093
29
0.41
0.41
0.41
0.4
0.39
CW 3000 Tough RO
33
0.38
0.38
0.38
0.37
0.36
A foam plastic product, reflective
38
0.35
0.35
0.35
0.34
0.33
foil backed
42
0.33
0.33
0.33
0.32
0.32
"K = 0.022 W/Mk"
46
0.32
0.31
0.31
0.31
0.30
50
0.30
0.30
0.30
0.29
0.28
 
55
0.28
0.28
0.28
0.27
0.27
Celotex Limited
Telephone 01473 822093
29
0.38
0.37
0.38
0.37
0.36
CW 2000 
33
0.35
0.35
0.35
0.34
0.33
A foam plastic product, reflective
36
0.34
0.33
0.35
0.33
0.32
foil backed
40
0.31
0.31
0.31
0.31
0.3
"K = 0.019 W/Mk"
44
0.30
0.29
0.29
0.29
0.28
 
48
0.28
0.28
0.28
0.27
0.27
Kingspan Insulations Limited
Telephone 01544 388601
30
0.4
0.4
0.4
0.39
0.38
Thermawall TW 50
35
0.37
0.36
0.37
0.36
0.35
HFCFC & CFC free
40
0.34
0.34
0.34
0.33
0.32
A foam plastic product, reflective
45
0.32
0.31
0.32
0.31
0.3
foil backed
50
0.3
0.29
0.3
0.29
0.28
"K = 0.022 W/Mk"
Kooltherm K8
CFC free
23
0.42
0.41
0.41
0.4
0.39
"K = 0.018 W/Mk"
30
0.36
0.36
0.36
0.35
0.34
35
0.33
0.33
0.33
0.32
0.31
40
0.3
0.3
0.3
0.3
0.29
45
0.28
0.28
0.28
0.27
0.27
 
50
0.26
0.26
0.26
0.26
0.25
Dow Construction Products
Telephone 0208 917 5050
40
0.39
0.39
0.39
0.38
0.37
Wallmate CWX
50
0.34
0.34
0.34
0.33
0.32
An extruded foam product
60
0.3
0.3
0.3
0.3
0.29
"K = 0.025 W/Mk"
            
Rockwool Limited
Telephone 01656 862621
40
0.47
0.46
0.46
0.45
0.44
HP Partial Fill
50
0.41
0.41
0.41
0.40
0.39
"K = 0.034 W/Mk"
60
0.37
0.36
0.37
0.36
0.35
65
0.35
0.35
0.35
0.34
0.33
 
75
0.32
0.32
0.32
0.31
0.30
Full Fill Cavity Insulation
"U-values attained W/m2K"
90mm
100mm
100mm
115mm
140mm
 
Insulation
Thickness
(mm)  
Solid
Cellular
Solid
Solid
Solid
Rockwool Limited
  
Telephone 01656 862621
65
0.39
0.38
0.39
0.38
0.37
Rockwool full fill cavity
80
0.34
0.33
0.33
0.33
0.32
Mineral wool slab
90
0.31
0.31
0.31
0.3
0.3
"K = 0.036 W/Mk"
100
0.29
0.28
0.28
0.28
0.27
Superglass Insulation Limited
Telephone 01786 451170
75
0.34
0.34
0.34
0.33
0.32
Superwall cavity slab
100
0.27
0.27
0.27
0.27
0.26
"K = 0.034 W/Mk"
125
0.23
0.23
0.23
0.23
0.22
 
150
0.2
0.2
0.2
0.2
0.19
Knauf Alcopor  
Telephone 01744 24022
75
0.35
0.35
0.35
0.34
0.33
Dritherm full fill
80
0.34
0.33
0.33
0.33
0.32
Cavity slab
85
0.32
0.32
0.32
0.32
0.31
"K = 0.036 W/Mk"
100
0.29
0.28
0.28
0.28
0.27
Rockwool Limited
Telephone 01656 862621
75
0.37
0.36
0.37
0.36
0.35
Rockwool full fill cavity
100
0.3
0.3
0.3
0.29
0.28
Blown Fibre
125
0.25
0.25
0.25
0.25
0.24
"K = 0.039 W/Mk"
           
Knauf Alcopor
Telephone 01744 24022
75
0.38
0.37
0.38
0.36
0.35
Superfill
100
0.3
0.3
0.31
0.3
0.29
Blown fibre
125
0.26
0.25
0.26
0.25
0.25
"K = 0.040 W/Mk"
            
90mm
100mm
100mm
  
115mm
Solid
Cellular
Solid
  
Solid

sales@besblock.co.uk
www.besblock.co.uk
Tel: 01952 685000
Fax: 01952 585224