U-Values of Walls Next to Unheated Spaces

Uo = U-value of the element between heated and unheated spaces calculated as if there was no unheated space adjacent to the element (see Table U o below)

Ru = effective thermal resistance of unheated space - see Table 3.1, SAP2001 (extract below).

U-Values for Solar Block with 10mm Joints

Uo (W/m2K)

440mm long x 215mm high blocks with 10mm joints

Solar
(mm)

External finish

Internal finish

100

115

125

150

200

250

No finish

Lwt plaster

1.06

0.96

0.90

0.79

0.63

0.52

12.5mm plasterboard on dabs

0.96

0.87

0.82

0.73

0.59

0.49

22mm ThermaLine BASIC

0.74

0.69

0.67

0.60

0.50

0.42

30mm Thermaline BASIC

0.65

0.60

0.58

0.53

0.45

0.39

40mm ThermaLine BASIC

0.56

0.52

0.51

0.46

0.40

0.35

45 ThermaLine PLUS

U-Values for Solar Block with 2mm Joints

440mm long x 215mm high blocks with 2mm joints

Solar
(mm)

External finish

Internal finish

100

115

125

150

200

250

No finish

Lwt plaster

0.91

0.81

0.76

0.66

0.52

0.42

12.5mm plasterboard on dabs

0.84

0.75

0.71

0.62

0.49

0.41

22mm ThermaLine BASIC

0.67

0.62

0.59

0.52

0.43

0.36

30mm Thermaline BASIC

0.59

0.55

0.53

0.47

0.39

0.34

40mm ThermaLine BASIC

0.52

0.48

0.46

0.42

0.36

0.31

U-Values for Standard Block with 10mm Joints

Uo (W/m2K)

440mm long x 215mm high blocks with 10mm joints

Standard
(mm)

External finish

Internal finish

100

150

200

250

No finish

Lwt plaster

1.26

0.95

0.76

0.64

12.5mm plasterboard on dabs

1.14

0.86

0.70

0.59

22mm ThermaLine BASIC

0.84

0.69

0.58

0.50

30mm Thermaline BASIC

0.72

0.60

0.52

0.46

40mm ThermaLine BASIC

0.61

0.52

0.46

0.41

45 ThermaLine PLUS

U-Values for Standard Block with 2mm Joints

440mm long x 215mm high blocks with 2mm joints

Standard
(mm)

External finish

Internal finish

100

150

200

250

No finish

Lwt plaster

1.13

0.83

0.66

0.55

12.5mm plasterboard on dabs

1.02

0.77

0.62

0.52

22mm ThermaLine BASIC

0.79

0.63

0.53

0.45

30mm Thermaline BASIC

0.68

0.56

0.47

0.41

40mm ThermaLine BASIC

0.58

0.49

0.42

0.37

U-Values for Hi-Seven  Block with 10mm Joints

440mm long x 215mm high blocks with 10mm joints

Hi-Seven
(mm)

External finish

Internal finish

100

250

275

No finish

Lwt plaster

1.43

0.74

0.69

12.5mm plasterboard on dabs

1.26

0.69

0.64

22mm ThermaLine BASIC

0.92

0.57

0.54

30mm Thermaline BASIC

0.78

0.51

0.48

40mm ThermaLine BASIC

0.65

0.45

0.43

45 ThermaLine PLUS

U-Values for Hi-Seven Block with 2mm Joints

440mm long x 215mm high blocks with 2mm joints

Hi-Seven
(mm)

External finish

Internal finish

100

250

275

No finish

Lwt plaster

1.32

0.66

0.61

12.5mm plasterboard on dabs

1.17

0.62

0.58

22mm ThermaLine BASIC

0.88

0.53

0.50

30mm Thermaline BASIC

0.75

0.48

0.45

40mm ThermaLine BASIC

0.63

0.42

0.40

An Extract from Table 3.1, SAP 2001:

Ru for a single garage

Garage type

Element between garage and dwelling

Where the insulated envelope of the dwelling goes round the outside of the garage

Where the walls separating the garage from the dwelling are the external walls

Single, fully integral

Side wall+ end wall + floor

0.68

0.33

One wall + floor

0.54

0.25

Single adjacent

One wall

0.23

0.09

This information has been sourced, reviewed and adapted from materials provided by H + H Celcon.

For more information on this source, please visit H + H Celcon.

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