Sprouto/rdsap10 huggingface dataset:
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Wall type |  |  |  |  |  |  |  |  |  |  |  |  |   |
|  Stone: granite or whinstone as built | According to 6.6 |  |  |  | 1.7 b | 1.0 | 0.60 | 0.45 | 0.45 | - | 0.30 | 0.28 | 0.18  |
|  Stone: sandstone or limestone as built |  |  |  |  | 1.7 b | 1.0 | 0.60 | 0.45 | 0.45 | - | 0.30 | 0.28 | 0.18  |
|  Solid brick as built | According to 6.7 |  |  |  | 1.7c | 1.0 | 0.60 | 0.45 | 0.45 | - | 0.30 | 0.28 | 0.18  |
|  Stone/solid brick with 50 mm external or internal insulation | According to 6.8 |  |  |  | 0.55 | $0.45^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.30^{*}$ | - | $0.21^{*}$ | $0.21^{*}$ | 0.15  |
|  Stone/solid brick with 100 mm external or internal insulation |  |  |  |  | 0.32 | $0.28^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | - | $0.17^{*}$ | $0.16^{*}$ | 0.12  |
|  Stone/solid brick with 150 mm external or internal insulation |  |  |  |  | 0.23 | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | - | $0.14^{*}$ | $0.14^{*}$ | 0.11  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Stone/solid brick with 150 mm external or internal insulation |  |  |  |  | 0.23 | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | - | $0.14^{*}$ | $0.14^{*}$ | 0.11  |
|  Stone/solid brick with 200 mm external or internal insulation |  |  |  |  | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | - | $0.12^{*}$ | $0.12^{*}$ | 0.09  |
|  Cob as built | 0.80 | 0.80 | 0.80 | 0.80 | 0.80 | 0.80 | 0.60 | 0.60 | 0.45 | - | 0.30 | 0.28 | 0.18  |
|  Cob with 50 mm external or internal insulation | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | - | $0.21^{*}$ | $0.21^{*}$ | $0.15^{*}$  |
|  Cob with 100 mm external or internal insulation | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | - | $0.21^{*}$ | $0.16^{*}$ | $0.12^{*}$  |
|  Cob with 150 mm external or internal insulation | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | - | 0.20 | $0.14^{*}$ | $0.11^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Cob with 150 mm external or internal insulation | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | - | 0.20 | $0.14^{*}$ | $0.11^{*}$  |
|  Cob with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | - | $0.12^{*}$ | $0.12^{*}$ | $0.09^{*}$  |
|  Cavity as built | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 1.0 | 0.60 | 0.45 | 0.45 | - | 0.30 | 0.28 | 0.18  |
|  Unfilled cavity with 50 mm external or internal insulation | 0.53 | 0.53 | 0.53 | 0.53 | 0.53 | 0.45 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | - | $0.21^{*}$ | $0.21^{*}$ | $0.15^{*}$  |
|  Unfilled cavity with 100 mm external or internal insulation | 0.32 | 0.32 | 0.32 | 0.32 | 0.32 | 0.30 | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | - | $0.17^{*}$ | $0.16^{*}$ | $0.12^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Unfilled cavity with 100 mm external or internal insulation | 0.32 | 0.32 | 0.32 | 0.32 | 0.32 | 0.30 | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | - | $0.17^{*}$ | $0.16^{*}$ | $0.12^{*}$  |
|  Unfilled cavity with 150 mm external or internal insulation | 0.23 | 0.23 | 0.23 | 0.23 | 0.23 | 0.21 | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | - | $0.14^{*}$ | $0.14^{*}$ | $0.11^{*}$  |
|  Unfilled cavity with 200 mm external or internal insulation | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | - | $0.12^{*}$ | $0.12^{*}$ | $0.09^{*}$  |
|  Filled cavity | 0.7 | 0.7 | 0.7 | 0.7 | 0.7 | 0.40 | 0.35 | $0.45^{t}$ | $0.45^{t}$ | - | $0.30^{t}$ | $0.28^{t}$ | $0.18^{t}$  |
|  Filled cavity with 50 mm external or internal insulation | 0.37 | 0.37 | 0.37 | 0.37 | 0.37 | 0.27 | $0.25^{*}$ | $0.25^{*}$ | $0.25^{*}$ | - | $0.25^{*}$ | $0.21^{*}$ | $0.15^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Filled cavity with 50 mm external or internal insulation | 0.37 | 0.37 | 0.37 | 0.37 | 0.37 | 0.27 | $0.25^{*}$ | $0.25^{*}$ | $0.25^{*}$ | - | $0.25^{*}$ | $0.21^{*}$ | $0.15^{*}$  |
|  Filled cavity with 100 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | 0.20 | $0.19^{*}$ | $0.19^{*}$ | $0.19^{*}$ | - | $0.19^{*}$ | $0.16^{*}$ | $0.12^{*}$  |
|  Filled cavity with 150 mm external or internal insulation | 0.19 | 0.19 | 0.19 | 0.19 | 0.19 | 0.16 | $0.15^{*}$ | $0.15^{*}$ | $0.15^{*}$ | - | $0.15^{*}$ | $0.14^{*}$ | $0.11^{*}$  |
|  Filled cavity with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.13 | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | - | $0.12^{*}$ | $0.12^{*}$ | $0.09^{*}$  |
|  Timber frame as built | 2.5 | 1.9 | 1.9 | 1.0 | 0.80 | 0.45 | 0.40 | 0.40 | 0.40 | - | 0.30 | 0.28 | 0.18  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Timber frame as built | 2.5 | 1.9 | 1.9 | 1.0 | 0.80 | 0.45 | 0.40 | 0.40 | 0.40 | - | 0.30 | 0.28 | 0.18  |
|  Timber frame with internal insulation | 0.60 | 0.55 | 0.55 | 0.40 | 0.40 | 0.40 | $0.40^{t}$ | $0.40^{t}$ | $0.40^{t}$ | - | $0.30^{t}$ | $0.28^{t}$ | $0.18^{t}$  |
|  System build as built | 2.0 | 2.0 | 2.0 | 2.0 | 1.7 | 1.0 | 0.60 | 0.45 | 0.45 | - | 0.30 | 0.28 | 0.18  |
|  System build with 50 mm external or internal insulation | 0.60 | 0.60 | 0.60 | 0.60 | 0.55 | 0.45 | $0.35^{*}$ | $0.30^{*}$ | $0.30^{*}$ | - | $0.21^{*}$ | $0.21^{*}$ | $0.15^{*}$  |
|  System build with 100 mm external or internal insulation | 0.35 | 0.35 | 0.35 | 0.35 | 0.35 | $0.32^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | - | $0.17^{*}$ | $0.16^{*}$ | $0.12^{*}$  |
|  System build with 150 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | - | $0.14^{*}$ | $0.14^{*}$ | $0.11^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  System build with 150 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | - | $0.14^{*}$ | $0.14^{*}$ | $0.11^{*}$  |
|  System build with 200 mm external or internal insulation | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | - | $0.12^{*}$ | $0.12^{*}$ | $0.09^{*}$  |  
a Or from equations in 6.6 if the calculated U-value is less than 1.7 . b Or from 6.7 if wall thickness is other than 200 mm to 280 mm c According to 6.8  
- wall may have had internal or external insulation when originally built; this applies only if insulation is known to have been increased subsequently (otherwise 'as built' applies) ${ }^{t}$ assumed as built If a wall is known to have additional insulation but the insulation thickness is unknown, use the row in the table for 50 mm insulation  
Table 9 : Wall U-values - Wales  
|  Age band | A | B | C | D | E | F | G | H | I | J | K | L | M  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
Table 9 : Wall U-values - Wales  
|  Age band | A | B | C | D | E | F | G | H | I | J | K | L | M  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  Wall type |  |  |  |  |  |  |  |  |  |  |  |  |   |
|  Stone: granite or whinstone | According to 6.6 |  |  |  | 1.7 a | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  Stone: sandstone or limestone |  |  |  |  | 1.7 a | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  Solid brick as built | According to 6.7 |  |  |  | 1.7b | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  Stone/solid brick with 50 mm external or internal insulation | According to 6.8 |  |  |  | 0.55 c | $0.45^{*}$ | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Stone/solid brick with 100 mm external or internal insulation |  |  |  |  | 0.32 c | $0.28^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Stone/solid brick with 150 mm external or internal insulation |  |  |  |  | 0.23 c | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Stone/solid brick with 200 mm external or internal insulation |  |  |  |  | 0.18 c | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
|  Cob (as built) | 0.80 | 0.80 | 0.80 | 0.80 | 0.80 | 0.80 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  Cob with 50 mm external or internal insulation | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Cob with 50 mm external or internal insulation | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Cob with 100 mm external or internal insulation | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Cob with 150 mm external or internal insulation | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Cob with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
|  Cavity as built | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Cavity as built | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  Unfilled cavity with 50 mm external or internal insulation | 0.53 | 0.53 | 0.53 | 0.53 | 0.53 | 0.45 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Unfilled cavity with 100 mm external or internal insulation | 0.32 | 0.32 | 0.32 | 0.32 | 0.32 | 0.30 | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Unfilled cavity with 150 mm external or internal insulation | 0.23 | 0.23 | 0.23 | 0.23 | 0.23 | 0.21 | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Unfilled cavity with 200 mm external or internal insulation | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Filled cavity | 0.7 | 0.7 | 0.7 | 0.7 | 0.7 | 0.40 | 0.35 | 0.35 | $0.45^{1}$ | $0.35^{1}$ | $0.30^{1}$ | $0.28^{1}$ | $0.18^{1}$  |
|  Filled cavity with 50 mm external or internal insulation | 0.37 | 0.37 | 0.37 | 0.37 | 0.37 | 0.27 | $0.25^{*}$ | $0.25^{*}$ | $0.25^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Filled cavity with 100 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | 0.20 | $0.19^{*}$ | $0.19^{*}$ | $0.19^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Filled cavity with 150 mm external or internal insulation | 0.19 | 0.19 | 0.19 | 0.19 | 0.19 | 0.16 | $0.15^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Filled cavity with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.13 | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Filled cavity with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.13 | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
|  Timber frame as built | 2.5 | 1.9 | 1.9 | 1.0 | 0.80 | 0.45 | 0.40 | 0.40 | 0.40 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  Timber frame with internal insulation | 0.60 | 0.55 | 0.55 | 0.40 | 0.40 | 0.40 | $0.40^{1}$ | $0.40^{1}$ | $0.40^{1}$ | $0.35^{1}$ | $0.30^{1}$ | $0.28^{1}$ | $0.18 / 0.21^{\mathrm{a} 1}$  |
|  System build as built | 2.0 | 2.0 | 2.0 | 2.0 | 1.7 | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | $0.18 / 0.21^{\mathrm{a}}$  |
|  System build with 50 mm external or internal insulation | 0.60 | 0.60 | 0.60 | 0.60 | 0.55 | 0.45 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  System build with 50 mm external or internal insulation | 0.60 | 0.60 | 0.60 | 0.60 | 0.55 | 0.45 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  System build with 100 mm external or internal insulation | 0.35 | 0.35 | 0.35 | 0.35 | 0.35 | $0.32^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  System build with 150 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  System build with 200 mm external or internal insulation | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |  
a Or from equations in 6.6 if the calculated $U$-value is less than 1.7 . b Or from 6.7 if wall thickness is other than 200 mm to 280 mm c According to 6.8
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
a Or from equations in 6.6 if the calculated $U$-value is less than 1.7 . b Or from 6.7 if wall thickness is other than 200 mm to 280 mm c According to 6.8  
- wall may have had internal or external insulation when originally built; this applies only if insulation is known to have been increased subsequently (otherwise 'as built' applies) ${ }^{1}$ assumed as built If a wall is known to have additional insulation but the insulation thickness is unknown, use the row in the table for 50 mm insulation. ${ }^{a} \mathrm{U}$-value $=0.18 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ applicable for houses; U -value $=0.21 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ applicable for flats  
Table 10 : Wall U-values - Isle of Man  
|  Age band | A | B | C | D | E | F | G | H | I | J | K | L | M  |
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  Wall type |  |  |  |  |  |  |  |  |  |  |  |  |   |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
| --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- | --- |
|  Wall type |  |  |  |  |  |  |  |  |  |  |  |  |   |
|  Stone: granite or whinstone | According to 6.6 |  |  |  | 1.7 a | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
|  Stone: sandstone or limestone |  |  |  |  | 1.7 a | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
|  Solid brick as built | According to 6.7 |  |  |  | 1.7b | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
|  Stone/solid brick with 50 mm external or internal insulation | According to 6.8 |  |  |  | 0.55 c | $0.45^{*}$ | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Stone/solid brick with 100 mm external or internal insulation |  |  |  |  | 0.32 c | $0.28^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Stone/solid brick with 100 mm external or internal insulation |  |  |  |  | 0.32 c | $0.28^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Stone/solid brick with 150 mm external or internal insulation |  |  |  |  | 0.23 c | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Stone/solid brick with 200 mm external or internal insulation |  |  |  |  | 0.18 c | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
|  Cob (as built) | 0.80 | 0.80 | 0.80 | 0.80 | 0.80 | 0.80 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
|  Cob with 50 mm external or internal insulation | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Cob with 50 mm external or internal insulation | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | 0.40 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Cob with 100 mm external or internal insulation | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | 0.26 | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Cob with 150 mm external or internal insulation | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | 0.20 | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Cob with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
|  Cavity as built | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Cavity as built | 1.5 | 1.5 | 1.5 | 1.5 | 1.5 | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
|  Unfilled cavity with 50 mm external or internal insulation | 0.53 | 0.53 | 0.53 | 0.53 | 0.53 | 0.45 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Unfilled cavity with 100 mm external or internal insulation | 0.32 | 0.32 | 0.32 | 0.32 | 0.32 | 0.30 | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Unfilled cavity with 150 mm external or internal insulation | 0.23 | 0.23 | 0.23 | 0.23 | 0.23 | 0.21 | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Unfilled cavity with 200 mm external or internal insulation | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Filled cavity | 0.7 | 0.7 | 0.7 | 0.7 | 0.7 | 0.40 | 0.35 | 0.35 | $0.45^{1}$ | $0.35^{1}$ | $0.30^{1}$ | $0.28^{1}$ | $0.26^{1}$  |
|  Filled cavity with 50 mm external or internal insulation | 0.37 | 0.37 | 0.37 | 0.37 | 0.37 | 0.27 | $0.25^{*}$ | $0.25^{*}$ | $0.25^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  Filled cavity with 100 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | 0.20 | $0.19^{*}$ | $0.19^{*}$ | $0.19^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
|  Filled cavity with 150 mm external or internal insulation | 0.19 | 0.19 | 0.19 | 0.19 | 0.19 | 0.16 | $0.15^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  Filled cavity with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.13 | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  Filled cavity with 200 mm external or internal insulation | 0.16 | 0.16 | 0.16 | 0.16 | 0.16 | 0.13 | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |
|  Timber frame as built | 2.5 | 1.9 | 1.9 | 1.0 | 0.80 | 0.45 | 0.40 | 0.40 | 0.40 | 0.35 | 0.30 | 0.28 | 0.26  |
|  Timber frame with internal insulation | 0.60 | 0.55 | 0.55 | 0.40 | 0.40 | 0.40 | $0.40^{1}$ | $0.40^{1}$ | $0.40^{1}$ | $0.35^{1}$ | $0.30^{1}$ | $0.28^{1}$ | $0.26^{1}$  |
|  System build as built | 2.0 | 2.0 | 2.0 | 2.0 | 1.7 | 1.0 | 0.60 | 0.60 | 0.45 | 0.35 | 0.30 | 0.28 | 0.26  |
|  System build with 50 mm external or internal insulation | 0.60 | 0.60 | 0.60 | 0.60 | 0.55 | 0.45 | $0.35^{*}$ | $0.35^{*}$ | $0.30^{*}$ | $0.25^{*}$ | $0.21^{*}$ | $0.21^{*}$ | $0.20^{*}$  |
|  System build with 100 mm external or internal insulation | 0.35 | 0.35 | 0.35 | 0.35 | 0.35 | $0.32^{*}$ | $0.24^{*}$ | $0.24^{*}$ | $0.21^{*}$ | $0.19^{*}$ | $0.17^{*}$ | $0.16^{*}$ | $0.15^{*}$  |
6.2.5 Dwelling adjacent to non-domestic (commercial) premises
6.4 Default U-values of external walls
|  System build with 150 mm external or internal insulation | 0.25 | 0.25 | 0.25 | 0.25 | 0.25 | $0.21^{*}$ | $0.18^{*}$ | $0.18^{*}$ | $0.17^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.14^{*}$ | $0.13^{*}$  |
|  System build with 200 mm external or internal insulation | 0.18 | 0.18 | 0.18 | 0.18 | 0.18 | $0.17^{*}$ | $0.15^{*}$ | $0.15^{*}$ | $0.14^{*}$ | $0.13^{*}$ | $0.12^{*}$ | $0.12^{*}$ | $0.11^{*}$  |  
a Or from equations in 6.6 if the calculated $U$-value is less than 1.7 . b Or from 6.7 if wall thickness is other than 200 mm to 280 mm c According to 6.8  
- wall may have had internal or external insulation when originally built; this applies only if insulation is known to have been increased subsequently (otherwise 'as built' applies) ${ }^{1}$ assumed as built If a wall is known to have additional insulation but the insulation thickness is unknown, use the row in the table for 50 mm insulation
6.5 U-values for Park home walls
Table 11 : Default U-values for park home walls  
| Age band | F | G | I | K | L | M |
| :-- | :--: | :--: | :--: | :--: | :--: | :--: |
| Park home as built | 1.7 | 1.2 | 0.7 | 0.6 | 0.6 | 0.6 |
| Park home with additional insulation | Entered U-value (see section 2.19.1) |  |  |  |  |  |
6.5 U-values for Park home walls
6.6 U-values of uninsulated stone walls, age bands A to E
Table 12 : Default U-values of stone walls  
| Stone wall type | Equation |
| :-- | :-- |
| Sandstone or limestone | $\mathrm{U}=54.876 \times \mathrm{W}^{-0.561}$ |
| Granite or whinstone: | $\mathrm{U}=45.315 \times \mathrm{W}^{-0.513}$ |  
Where: W is wall thickness, mm
Apply the adjustment according to Table 14 : Insulation thickness and corresponding resistance if wall is insulated or dry-lined including lath and plaster.
6.5 U-values for Park home walls
6.7 U-values for uninsulated brick walls, age bands A to E
Table 13 : Default U-values of brick walls  
| Wall thickness, mm | U-value, W/m2K |
| :-- | :--: |
| Up to 200 mm | 2.5 |
| 200 to 280 mm | 1.7 |
| 280 to 420 mm | 1.4 |
| More than 420 mm | 1.1 |  
Apply the adjustment according to Table 14 : Insulation thickness and corresponding resistance if wall is insulated or/and dry-lined including lath and plaster.
6.5 U-values for Park home walls
6.8 U-value for insulated walls in age bands A to E
This applies to walls in age bands A to E with insulation, dry-lining or lath and plaster:  
1. Obtain the U -value $\left(U_{0}\right)$ of the wall without insulation or dry-lining from the corresponding table of wall U-values (e.g. one of Tables 6 to 10). Call this $U_{0}$.
2. The U -value of the insulated wall is  
$$
U=\frac{1}{\frac{1}{U_{0}}+R_{\text {insulation }}}
$$  
Where:
$U_{0}$ is a U-value of the building element without insulation, $\mathrm{W} / \mathrm{m}^{2} \mathrm{~K}$ (e.g. Tables 6, 7. 8.9 or 10)
$R_{\text {insulation }}$ is the additional thermal resistance introduced by the insulation or internal finish obtained from Table 14 : Insulation thickness and corresponding resistance.  
Table 14 : Insulation thickness and corresponding resistance  
| Insulation <br> thickness <br> T, mm | $R_{\text {insulation }}\left(\mathrm{m}^{2} \mathrm{~K} / \mathrm{W}\right)$ |  |  |
| :-- | :--: | :--: | :--: |
6.5 U-values for Park home walls
6.8 U-value for insulated walls in age bands A to E
| Insulation <br> thickness <br> T, mm | $R_{\text {insulation }}\left(\mathrm{m}^{2} \mathrm{~K} / \mathrm{W}\right)$ |  |  |
| :-- | :--: | :--: | :--: |
|  | $\lambda=0.04 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ | $\lambda=0.03 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ (optional) | $\lambda=0.025 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ |
| 10 mm | 0.5 | 0.58 | 0.65 |
| 25 mm | 0.875 | 1.08 | 1.25 |
| 50 mm | 1.5 | 1.92 | 2.25 |
| 75 mm | 2.125 | 2.75 | 3.25 |
| 100 mm | 2.75 | 3.58 | 4.25 |
| 125 mm | 3.375 | 4.42 | 5.25 |
| 150 mm | 4 | 5.25 | 6.25 |
| 175 mm | 4.625 | 6.08 | 7.25 |
| 200 mm | 5.25 | 6.92 | 8.25 |  
$\lambda=0.04 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ is typical for mineral wool, rock wool, fibre glass or EPS (expanded polystyrene);
$\lambda=0.03 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ (optional) typical for XPS (extruded polystyrene),
6.5 U-values for Park home walls
6.8 U-value for insulated walls in age bands A to E
$\lambda=0.03 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ (optional) typical for XPS (extruded polystyrene),
$\lambda=0.025 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ is typical for PUR (polyurethane foam), PIR (polyisocyanurate), phenolic foam.
For drylining including laths and plaster use $R_{\text {insulation }}=0.17 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$.
Thickness of render is included in the thickness of uninsulated wall.  
If thickness of insulation is in between of the values given in this table, the resistance value can be interpolated by using equations:
$\mathrm{R}=0.04 * \mathrm{~T}+0.25$ when $\lambda=0.025 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$
$\mathrm{R}=0.0333 * \mathrm{~T}+0.248$ when $\lambda=0.03 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$
$\mathrm{R}=0.025 * \mathrm{~T}+0.25$ when $\lambda=0.04 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$
Where T is thickness of insulation in mm
6.9 U-values of sheltered walls (adjacent to unheated corridor or stairwell)
For sheltered walls of flats and maisonettes (between the dwelling and an unheated corridor or stairwell), the U-value for the applicable wall area is adjusted as described in SAP10.2 specification Section 3.3
$U=\frac{1}{\frac{1}{U_{0}}+R_{n}}$
Where:
$U_{o}$ is a U-value of the building element without insulation, W/m2K (e.g. from Tables S6, S7 or S8) or for insulated walls calculated according to sections $\mathbf{6 . 5}$ to $\mathbf{6 . 8}$.
$R_{u}$ is the additional thermal resistance,
Use $\mathbf{R}_{\mathbf{n}}=\mathbf{0 . 5} \mathbf{m}^{2} \mathbf{K} / \mathbf{W}$ for corridors and $\mathbf{R}_{\mathbf{n}}=\mathbf{2 . 1} \mathbf{m}^{2} \mathbf{K} / \mathbf{W}$ for stairwell (the values are from the SAP10.2 specification).
6.10 U-values of party walls and walls adjacent to heated corridor and stairwell
The U-value of party walls is taken from Table 15.
Table 15 : U-values of party walls  
| Party wall type | Party wall U-value |
| :-- | :--: |
| Solid masonry / timber frame / system built | 0.0 |
| Cavity masonry unfilled | 0.5 |
| Cavity masonry filled | 0.2 |
| Unable to determine, house or bungalow | 0.25 |
| Unable to determine, flat or maisonette* | 0.0 |  
*Note. In the case of flats and maisonettes it is assumed that the construction is such as to avoid a thermal bypass.
6.10 U-values of party walls and walls adjacent to heated corridor and stairwell
6.11.1 Roof insulation present at both joists and rafters
In the case of roofs, the boundary between the heated space and unheated roof space is usually the finished ceiling of the upper level of the dwelling. The heatloss calculation is based on the U-value at the ceiling level.  
If joist and rafter insulation are both present record joist insulation only. This is because roof U-value greatly depends on the air changes per hour in the unheated loft space and therefore the presence of insulation at rafters does not affect the U-value at joists, unless roof space is fully airtight (e.g. ventilation rate is less than 0.5 air changes per hour). As we do not measure the ventilation rate in the loft space, RdSAP assumes that the loft space is ventilated.
6.10 U-values of party walls and walls adjacent to heated corridor and stairwell
6.11.2 Roof U-values when loft insulation thickness at joists is known.
The U-value assumed for a pitched roof with an insulated ceiling or the insulation at rafter level should, where possible, be based on the observed thickness of the loft insulation according to Table 16.  
Table 16 : Roof U-values when loft insulation thickness is known  
| Insulation <br> thickness <br> (mm) | Assumed roof U-value (W/m²) at the ceiling level. |  |  |
| :--: | :--: | :--: | :--: |
|  | Insulation at joists <br> at ceiling level <br> and flat roof <br> (1) | Insulation at rafters <br> but U-value is attributed <br> to the ceiling area <br> (2) | Insulation at joists <br> (thatched roof only) <br> (3) |
| None | 2.3 | 2.3 | 0.35 |
| 12 | 1.5 | 1.75 | 0.32 |
| 25 | 1.0 | 1.30 | 0.30 |
| 50 | 0.68 | 0.88 | 0.25 |
| 75 | 0.50 | 0.67 | 0.22 |
| 100 | 0.40 | 0.54 | 0.20 |
| 125 | 0.35 | 0.45 | 0.18 |
| 150 | 0.30 | 0.39 | 0.17 |
| 175 | 0.25 | 0.32 | 0.15 |
| 200 | 0.21 | 0.29 | 0.14 |
| 225 | 0.19 | 0.25 | 0.13 |
| 250 | 0.17 | 0.23 | 0.12 |  
| 270 | 0.16 | 0.21 | 0.12 |
6.10 U-values of party walls and walls adjacent to heated corridor and stairwell
6.11.2 Roof U-values when loft insulation thickness at joists is known.
| 150 | 0.30 | 0.39 | 0.17 |
| 175 | 0.25 | 0.32 | 0.15 |
| 200 | 0.21 | 0.29 | 0.14 |
| 225 | 0.19 | 0.25 | 0.13 |
| 250 | 0.17 | 0.23 | 0.12 |  
| 270 | 0.16 | 0.21 | 0.12 |
| :--: | :--: | :--: | :--: |
| 300 | 0.14 | 0.19 | 0.11 |
| 350 | 0.12 | 0.16 | 0.10 |
| $>=400$ | 0.11 | 0.14 | 0.09 |  
Note: The U-values in Table 16 : take account of timber joists. The insulation is taken as being between joists only up to 150 mm , and between and over joists thereafter. It also takes into the account sheltering effect of unheated roof space.  
The U-values in Table 16 are for mineral wool or expanded polystyrene insulation.
In other cases, unless provided by the assessor the U-value is taken from Table 18.
For a pitched roof with no access, use the column (1) for 'at joists" in Table 18.
6.11.3 Roof Room insulation where thickness of insulation is known.
The U-value assumed for a Room in Roof where thickness of insulation is known should, where possible, be based on the observed thickness of the insulation and the corresponding U-values according to Table 17.  
Table 17 : U-values applicable to rooms in roof (RR) where insulation thickness is known.  
| Insulation <br> thickness <br> (mm) | Insulated slope sloping ceiling U-value <br> (1) |  | Insulated slope flat ceiling U-value <br> (2) |  | Stud wall u-value For Room in Roof <br> (3) |  |
| :--: | :--: | :--: | :--: | :--: | :--: | :--: |
|  | Mineral wool or EPS slab (1a) | PUR or PIR optional (1b) | Mineral wool or EPS slab (2a) | PUR or PIR Optional (2b) | Mineral wool or EPS slab (3a) | PUR or PIR optional (3b) |
| none | 2.3 |  |  |  | 2.3 |  |
| 12 | 1.5 | 1.25 | 1.75 | 1.5 | 0.95 | 0.85 |
| 25 | 1 | 0.8 | 1.25 | 1 | 0.7 | 0.6 |
| 50 | 0.68 | 0.52 | 0.88 | 0.69 | 0.52 | 0.45 |
| 75 | 0.5 | 0.38 | 0.67 | 0.51 | 0.43 | 0.35 |
| 100 | 0.4 | 0.3 | 0.54 | 0.41 | 0.36 | 0.29 |
6.11.3 Roof Room insulation where thickness of insulation is known.
| 25 | 1 | 0.8 | 1.25 | 1 | 0.7 | 0.6 |
| 50 | 0.68 | 0.52 | 0.88 | 0.69 | 0.52 | 0.45 |
| 75 | 0.5 | 0.38 | 0.67 | 0.51 | 0.43 | 0.35 |
| 100 | 0.4 | 0.3 | 0.54 | 0.41 | 0.36 | 0.29 |
| 125 | 0.35 | 0.25 | 0.45 | 0.34 | 0.31 | 0.24 |
| 150 | 0.3 | 0.21 | 0.39 | 0.29 | 0.27 | 0.21 |
| 175 | 0.25 | 0.17 | 0.32 | 0.23 | 0.24 | 0.19 |
| 200 | 0.21 | 0.15 | 0.29 | 0.2 | 0.22 | 0.17 |
| 225 | 0.19 | 0.13 | 0.25 | 0.18 | 0.2 | 0.15 |
| 250 | 0.17 | 0.11 | 0.23 | 0.15 | 0.18 | 0.14 |
| 270 | 0.16 | 0.1 | 0.21 | 0.14 | 0.17 | 0.13 |
| 300 | 0.14 | 0.09 | 0.19 | 0.13 | 0.16 | 0.12 |
| 350 | 0.12 | 0.08 | 0.16 | 0.11 | 0.14 | 0.11 |
| $>400$ | 0.11 | 0.07 | 0.14 | 0.09 | 0.12 | 0.1 |  
Key: EPS - expanded polystyrene slab; PUR - polyurethane rigid insulation; PIR - polyisocyanurate rigid foam
In other cases, unless provided by the assessor the U-value is taken from Table 18.
6.11.4 Assumed U-values when thickness of insulation cannot be determined.
U-values in Table 18 are used when thickness of insulation cannot be determined.
If retrofit insulation present of unknown thickness use 50 mm .  
Table 18 : Assumed roof U-values when Table 16 or Table 17 do not apply  
| Age band | Assumed Roof U-value $\left(\mathrm{W} / \mathrm{m}^{2} \mathrm{~K}\right)^{(a)}$ |  |  |  |  |  |  |
| :--: | :--: | :--: | :--: | :--: | :--: | :--: | :--: |
|  | Pitched, slates or tiles, insulation between joists or unknown <br> (1) | Pitched, slates or tiles, insulation at rafters <br> (2) | Flat roof ${ }^{(b)}$ <br> (3) | Room-inroof, all elements <br> (4) | Thatched roof ${ }^{(c)}$ <br> (5) | Thatched roof, room-inroof <br> (6) | Park home <br> (7) |
| $\begin{aligned} & \hline \mathbf{A}, \mathbf{B}, \\ & \mathbf{C}, \mathbf{D} \end{aligned}$ | $0.40(100 \mathrm{~mm})^{(1)(4)}$ | $2.3^{(1)}$ | $2.3^{(1)}$ | $2.3^{(1)}$ | 0.35 | 0.25 | - |
| E | $0.40(100 \mathrm{~mm})^{(1)(4)}$ | $1.5^{(1)}$ | $1.5^{(1)}$ | $1.5^{(1)}$ | 0.35 | 0.25 | - |
6.11.4 Assumed U-values when thickness of insulation cannot be determined.
| E | $0.40(100 \mathrm{~mm})^{(1)(4)}$ | $1.5^{(1)}$ | $1.5^{(1)}$ | $1.5^{(1)}$ | 0.35 | 0.25 | - |
| F | $0.40(100 \mathrm{~mm})^{(1)(4)}$ | $0.68^{(1)}$ | $0.68^{(1)}$ | $0.80^{(1)}$ | 0.35 | 0.25 | 1.7 |
| G | $0.40(100 \mathrm{~mm})^{(1)}$ | $0.40^{(1)}$ | $0.40^{(1)}$ | $0.50^{(1)}$ | 0.35 | 0.25 | 0.6 |
| H | $0.30(150 \mathrm{~mm})^{(1)}$ | $0.35^{(1)}$ | $0.35^{(1)}$ | $0.35^{(1)}$ | 0.35 | 0.25 | - |
| I | $0.26(170 \mathrm{~mm})^{(1)}$ | $0.35^{(1)}$ | $0.35^{(1)}$ | $0.35^{(1)}$ | 0.35 | 0.25 | 0.35 |
| J | $0.16(270 \mathrm{~mm})^{(1)}$ | $0.20^{(1)}$ | $0.25^{(1)}$ | $0.30^{(1)}$ | 0.30 | 0.25 | - |
| K | $0.16(270 \mathrm{~mm})^{(1)}$ | $0.20^{(1)}$ | $0.25^{(1)(2)}$ | $0.25^{(1)(2)}$ | $0.25^{(2)}$ | $0.25^{(2)}$ | 0.30 |
| L | $0.16^{(3)}(270 \mathrm{~mm})^{(1)}$ | $0.18^{(1)}$ | $0.18^{(1)}$ | $0.18^{(1)}$ | 0.18 | 0.18 | - |
| M | $0.15(300 \mathrm{~mm})^{(1)}$ | $0.15^{(1)}$ | $0.15^{(1)}$ | $0.15^{(1)}$ | 0.15 | 0.15 | 0.15 |
6.11.4 Assumed U-values when thickness of insulation cannot be determined.
| M | $0.15(300 \mathrm{~mm})^{(1)}$ | $0.15^{(1)}$ | $0.15^{(1)}$ | $0.15^{(1)}$ | 0.15 | 0.15 | 0.15 |  
(a) If the roof insulation is "none" use $\mathrm{U}=2.3$ (all roof types, except for thatched roofs); it takes into the account sheltering effect of unheated roof space.
(b) Applies also to roof with sloping ceiling and "unheated space above the building part". See also 2.14 .
(c) For thatched roofs if there is also retro-fitted insulation between the rafters reduce the U -value to $U=\frac{1}{\frac{1}{U_{\text {table }}}+R_{\text {ins }}}$ where $R_{\text {ins }}$ is $0.7 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$ for $50 \mathrm{~mm}, 1.4 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$ for 100 mm and $2.1 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$ for 150 mm .
${ }^{(1)}$ The value from the table applies for unknown and as built.
${ }^{(2)} 0.20 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ in Scotland
${ }^{(3)} 0.15 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ in Scotland
6.11.4 Assumed U-values when thickness of insulation cannot be determined.
${ }^{(2)} 0.20 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ in Scotland
${ }^{(3)} 0.15 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ in Scotland
${ }^{(4)}$ Most lofts are insulated to at least 100 mm insulation  
In the case of roof rooms, the insulation thickness on the flat part of the ceiling should be measured where possible and the U -value taken from column (2) in Table 17.
The U-value of the remaining parts of the roof rooms, i.e. walls and sloping ceilings, is taken from Table 18 according to the age band of the roof rooms, unless evidence is available as to the insulation of these parts in which case column (1) in Table 17 applies.  
There is no heat loss through the roof of a building part that has the same dwelling above or another dwelling above.
6.11.4 Assumed U-values when thickness of insulation cannot be determined.
There is no heat loss through the roof of a building part that has the same dwelling above or another dwelling above.  
Note: These U-values take account of joists. They may differ from Elemental U-values in regulations applicable at the time of construction, where the Elemental $U$-values in regulations (up to age band $H$ ) were set on the basis of ignoring joists in $U$-value calculations.
6.12 U-values of floors next to the ground
Unless provided by the assessor the floor U-value is calculated according to BS EN ISO 13370 using its area (A) and exposed perimeter (P) and rounded to two decimal places. Floor U-values are obtained separately for the main dwelling and for any extension, using the applicable area, exposed perimeter and wall thickness.
The following parameters are used:  
- wall thickness (w) in metres as provided in the RdSAP data set or from Table 3 : Wall thickness (mm) if thickness unknown
- soil type clay (thermal conductivity $\lambda_{\mathrm{g}}=1.5 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$ )
$-\mathrm{R}_{\mathrm{si}}=0.17 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$
$-\mathrm{R}_{\mathrm{se}}=0.04 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$
- floor construction as specified by assessor, or from Table 19 if unknown
- all-over floor insulation of thickness as provided by the assessor or from Table 19 if unknown
6.12 U-values of floors next to the ground
- floor construction as specified by assessor, or from Table 19 if unknown
- all-over floor insulation of thickness as provided by the assessor or from Table 19 if unknown
- thermal conductivity of floor insulation $0.035 \mathrm{~W} / \mathrm{m} \cdot \mathrm{K}$
(so that $\mathrm{R}_{\mathrm{f}}=0.001^{*} \mathrm{~d}_{\mathrm{ins}} / 0.035$ where $\mathrm{d}_{\mathrm{ins}}$ if the insulation thickness in mm )
A non-separated conservatory has an uninsulated solid ground floor and wall thickness 300 mm .
A park home has a suspended timber floor.
For solid ground floors  
1. $\mathrm{d}_{\mathrm{t}}=\mathrm{w}+\lambda_{\mathrm{g}} \times\left(\mathrm{R}_{\mathrm{si}}+\mathrm{R}_{\mathrm{f}}+\mathrm{R}_{\mathrm{se}}\right)$
2. $\mathrm{B}=2 \times \mathrm{A} / \mathrm{P}$
3. if $\mathrm{d}_{\mathrm{t}}<\mathrm{B}, \mathrm{U}=2 \times \lambda_{\mathrm{g}} \times \ln \left(\pi \times \mathrm{B} / \mathrm{d}_{\mathrm{t}}+1\right) /\left(\pi \times \mathrm{B}+\mathrm{d}_{\mathrm{t}}\right)$
6.12 U-values of floors next to the ground
4. if $\mathrm{d}_{\mathrm{t}}>=\mathrm{B}, \mathrm{U}=\lambda_{\mathrm{g}} /\left(0.457 \times \mathrm{B}+\mathrm{d}_{\mathrm{t}}\right)$  
For suspended ground floors:  
- thermal resistance of floor deck $\mathrm{R}_{\mathrm{f}}=0.2 \mathrm{~m}^{2} \mathrm{~K} / \mathrm{W}$ if uninsulated,
or $\mathrm{R}_{\mathrm{f}}=$ thermal resistance of insulation +0.2 if insulated
- height above external ground level $\mathrm{h}=0.3 \mathrm{~m}$
- average wind speed at 10 m height $\mathrm{v}=5 \mathrm{~m} / \mathrm{s}$
- wind shielding factor $\mathrm{f}_{\mathrm{w}}=0.05$
- ventilation openings per m exposed perimeter $\varepsilon=0.003 \mathrm{~m}^{2} / \mathrm{m}$
- U-value of walls to underfloor space $\mathrm{U}_{\mathrm{w}}=1.5 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$  
1. $\mathrm{d}_{\mathrm{g}}=\mathrm{w}+\lambda_{\mathrm{g}} \times\left(\mathrm{R}_{\mathrm{si}}+\mathrm{R}_{\mathrm{se}}\right)$
2. $\mathrm{B}=2 \times \mathrm{A} / \mathrm{P}$
6.12 U-values of floors next to the ground
1. $\mathrm{d}_{\mathrm{g}}=\mathrm{w}+\lambda_{\mathrm{g}} \times\left(\mathrm{R}_{\mathrm{si}}+\mathrm{R}_{\mathrm{se}}\right)$
2. $\mathrm{B}=2 \times \mathrm{A} / \mathrm{P}$
3. $\mathrm{U}_{\mathrm{g}}=2 \times \lambda_{\mathrm{g}} \times \ln \left(\pi \times \mathrm{B} / \mathrm{d}_{\mathrm{g}}+1\right) /\left(\pi \times \mathrm{B}+\mathrm{d}_{\mathrm{g}}\right)$
4. $\mathrm{U}_{\mathrm{x}}=\left(2 \times \mathrm{h} \times \mathrm{U}_{\mathrm{w}} / \mathrm{B}\right)+\left(1450 \times \varepsilon \times \mathrm{v} \times \mathrm{f}_{\mathrm{w}} / \mathrm{B}\right)$
5. $\mathrm{U}=1 /\left(2 \times \mathrm{R}_{\mathrm{si}}+\mathrm{R}_{\mathrm{f}}+1 /\left(\mathrm{U}_{\mathrm{g}}+\mathrm{U}_{\mathrm{x}}\right)\right)$  
Table 19 : Basis for floor U-value calculation for ground floors when insulation thickness is unknown  
| Age band | Floor construction ${ }^{(1)}$ | All-over floor insulation ${ }^{(2)}$ |  |  |  |
| :-- | :-- | :-- | :-- | :-- | :-- |
6.12 U-values of floors next to the ground
| Age band | Floor construction ${ }^{(1)}$ | All-over floor insulation ${ }^{(2)}$ |  |  |  |
| :-- | :-- | :-- | :-- | :-- | :-- |
|  |  | England \& <br> Wales | Scotland | Northern <br> Ireland | Park <br> home ${ }^{(3)}$ |
| A, B | suspended timber ${ }^{(4)}$ | none | none | none | - |
| C to F | solid | none | none | none | none |
| G | solid | none | none | none | 25 mm |
| H | solid | none | 25 mm | 25 mm | - |
| I | solid | 25 mm | 50 mm | 50 mm | 50 mm |
| J | solid | 75 mm | 75 mm | - | - |
| K | solid | 100 mm | 100 mm | 100 mm | 70 mm |
| L | solid | 100 mm | 120 mm | 100 mm | - |
| M | solid | 140 mm | 180 mm | 140 mm | 100mm |
| ${ }^{(1)}$ Where floor construction is unknown |  |  |  |  |  |  
${ }^{(2)}$ For floors which have retrofitted insulation, use the greater of 50 mm and the thickness according to the age band.
${ }^{(3)}$ Suspended timber in all cases.
${ }^{(4)}$ Solid ground floor if underfloor heating.
6.13 U-values of exposed and semi-exposed upper floors
U-values of exposed and semi-exposed upper floors may be available to the assessor.
Otherwise, to simplify data collection no distinction is made in terms of U-value between an exposed floor (to outside air below) and a semi-exposed floor (to an enclosed but unheated space below) and the U-values in Table 20 are used.  
Table 20 : Exposed/Semi-exposed floor U-values  
| Age band | U-value $\left(\mathbf{W} / \mathbf{m}^{\mathbf{2}} \mathbf{K}\right)$ |  |  |  |
| :--: | :--: | :--: | :--: | :--: |
|  | Insulation unknown or as built | Insulated 50 mm | Insulated 100 mm | Insulated 150 mm |
| A to G | 1.20 | $0.50^{(1)}$ | 0.30 | 0.22 |
| H or I | 0.51 | $0.50^{(1)}$ | 0.30 | 0.22 |
| J | 0.25 | 0.25 | 0.25 | 0.22 |
| K | 0.22 | 0.22 | 0.22 | 0.22 |
| L | $0.22^{(2)}$ | $0.22^{(2)}$ | $0.22^{(2)}$ | $0.22^{(2)}$ |
| M | $0.18^{(3)}$ | $0.18^{(3)}$ | $0.18^{(3)}$ | $0.18^{(3)}$ |
6.13 U-values of exposed and semi-exposed upper floors
| J | 0.25 | 0.25 | 0.25 | 0.22 |
| K | 0.22 | 0.22 | 0.22 | 0.22 |
| L | $0.22^{(2)}$ | $0.22^{(2)}$ | $0.22^{(2)}$ | $0.22^{(2)}$ |
| M | $0.18^{(3)}$ | $0.18^{(3)}$ | $0.18^{(3)}$ | $0.18^{(3)}$ |
| ${ }^{(1)}$ Use these values if known to be insulated but insulation thickness not known <br> ${ }^{(2)} 0.18 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ in Scotland <br> ${ }^{(3)} 0.15 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ in Scotland and Wales |  |  |  |  |
6.13 U-values of exposed and semi-exposed upper floors
6.14 U-value of floor above a partially heated space
The U-value of a floor above partially heated premises is taken as $0.7 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$. This applies typically for a flat above non-domestic premises that are not heated to the same extent or duration as the flat.
6.13 U-values of exposed and semi-exposed upper floors
6.15 Allowance for thermal bridging
The thermal bridging factor, y, as defined in Appendix K is taken from Table 21 : Thermal bridging.
Table 21 : Thermal bridging  
|  | Thermal bridging factor <br> $\mathbf{y}\left(\mathbf{W} / \mathbf{m}^{\mathbf{2}} \mathbf{K}\right)$ |  |
| :-- | :--: | :--: |
| Age band | Not Park home | Park home |
| A to I | 0.15 | 0.15 |
| J | 0.11 | 0.15 |
| K, L, M | 0.08 | 0.15 |  
Thermal bridging factor " $y$ " is determined according to the age band of the main dwelling and applied to the all the exposed area including main dwelling, extensions, and non-separated conservatory.
6.16 Thermal Mass
The thermal mass parameter is taken as:
Table 22 : Thermal mass parameter  
| Construction type of main building | Thermal mass parameter |
| :-- | :-- |
| Timber frame, cob and park home (the three types regardless of <br> presence of internal insulation) <br> or <br> masonry including stone, solid brick, cavity walls and system built <br> (all four types with internal insulation) | $100 \mathrm{~kJ} / \mathrm{m}^{2} \mathrm{~K}$ |
| Masonry including stone, solid brick, cavity walls and system built <br> (all four types without internal insulation) | $250 \mathrm{~kJ} / \mathrm{m}^{2} \mathrm{~K}$ |
6.16 Thermal Mass
6.17 Basement U-values
For basement walls and floors use values in Table 23 : Basement U-values
Table 23 : Basement U-values  
| Age band | U-value $\left(\mathbf{W} / \mathbf{m}^{\mathbf{2}} \mathbf{K}\right)$ |  |
| :-- | :--: | :--: |
|  | Basement Wall | Basement Floor |
| A to E | 0.7 | 0.50 |
| F | 0.7 | 0.50 |
| G to H | 0.6 | 0.5 |
| I | 0.45 | 0.5 |
| J | 0.35 | 0.25 |
| K | 0.3 | 0.22 |
| L | 0.28 | 0.22 |
| M | 0.26 | 0.18 |  
If there is a floor above a basement it is treated as if it were a ground floor for heat loss purposes.
6.16 Thermal Mass
6.18 Curtain wall - U-value and other parameters
See section 2.5 for the definition of a curtain wall.
If documentary evidence is available, use calculated U-value of the whole curtain wall.
Otherwise for the purpose of RdSAP, $\mathrm{U}=2.0 \mathrm{~W} / \mathrm{m}^{2} \mathrm{~K}$ for pre-2023 curtain walls,
And for post-2023 (2024 in Scotland) U-values as for windows given in Notes below Table 24.
For the whole wall curtain walls use Frame Factor=1.
Software should have a provision for specifying curtain wall.
7 CONSERVATORY
7.1 Non-separated conservatory
The floor area and volume of a non-separated conservatory are added to the total floor area and volume of the dwelling. Its roof area is taken as its floor area divided by $\cos \left(20^{\circ}\right)$, and wall area is taken as the product of its exposed perimeter and its height. Its height is estimated from the equivalent number of storey heights of the dwelling to the nearest half storey (based on average internal height within the conservatory). The conservatory walls and roof are taken as fully glazed (and this glazed area applied in addition to measured window areas ). Glazed walls are taken as windows, glazed roof as rooflight, see window U-values in Table 24 : Window characteristics.  
The number of storey heights are translated into an actual height according to:  
- 1 storey: ground floor room height
- $11 / 2$ storey: ground floor room height $+0.25+0.5^{*}$ (first floor room height)
- 2 storey: ground floor room height $+0.25+$ first floor room height
etc.
7 CONSERVATORY
7.2 Separated conservatory.
A separated conservatory with or without fixed heaters is disregarded.
7 CONSERVATORY
8 SOLAR GAINS
Solar gains are calculated for average overshading (SAP10.2 Table 6d). When all windows are measured the collected data includes the orientation of each window.
7 CONSERVATORY
9 WINDOWS AND DOORS
A window is an opening in an external wall or roof of a building, fitted with glass or similar material, usually in a frame, that admits light.
A door may be treated as a window if it is considered to be highly glazed. Examples of highly glazed doors are patio doors, fully glazed doors, or French doors.
If in doubt, measure it and treat as a window if glazing area is $60 \%$ or more.