Building Elements Schema
This page defines the data model used to define all building element types.
Wall Types
Walls types are separated by category: External, Internal or Known U-Value.
External walls
A wall that separates the property from the outside.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Wall name | - | ✳️ | |
| Age band | - | ✳️ | |
| Construction type | - | ✳️ | |
| Additional insulation | - | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Tables S6-S8 |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Internal walls
A wall that partitions rooms within the same property.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Wall name | - | ✳️ | |
| Internal wall construction | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.18 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Party walls
A wall that separates the property from a neighbouring building.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Wall name | - | ✳️ | |
| Construction type | - | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Tables S8B |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Known U-value walls
A wall that has a measured or design U-value.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Wall name | - | ✳️ | |
| U-value | W/m².K | ✳️ | |
| Thermal bridging | W/m².K | CIBSE DHDG Table 3.4 |
Floor Types
Floors types are separated by category: Ground, Exposed, Internal or Known U-Value.
Ground floors
A floor that separates the property from the ground with unknown or no insulation.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| Floor construction | - | ✳️ | |
| Age band | - | ✳️ | |
| Wall construction | - | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Section S5.5 + Table S3 |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Ground floors (known insulation)
A floor that separates the property from the ground with known insulation level.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| Floor construction | - | ✳️ | |
| Insulation thickness | mm | ✳️ | |
| Wall thickness | mm | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Section S5.5 |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Exposed floors
A floor that separates the property from an unheated space (e.g. garage) or outside air (flying freehold).
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| Age band | - | ✳️ | |
| Insulation level | - | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Table S12 |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Internal floors
A floor that separates different storeys within the same property.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| Internal floor construction | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.27 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Party floors
A floor that separates different different flats/apartments or maisonettes.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| Internal floor construction | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.27 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Known U-value floors
A floor that has a measured or design U-value.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| U-value | W/m².K | ✳️ | |
| Thermal bridging | W/m².K | CIBSE DHDG Table 3.4 |
Ceiling and Roof Types
Ceiling and roof types are separated by category: External, Internal or Known U-Value.
External ceilings
A ceiling that separates the property from a loft or the outside air.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Ceiling name | - | ✳️ | |
| Age band | - | ✳️ | |
| Roof type | - | ✳️ | |
| Insulation thickness | mm | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Table S9 or S10 |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Internal ceilings
A ceiling that separates different storeys within the same property.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Ceiling name | - | ✳️ | |
| Internal ceiling construction | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.27 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Party ceilings
A ceiling that separates different different flats/apartments or maisonettes.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Floor name | - | ✳️ | |
| Internal floor construction | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.27 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Known U-value ceilings
A ceiling that has a measured or design U-value.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Ceiling name | - | ✳️ | |
| U-value | W/m².K | ✳️ | |
| Thermal bridging | W/m².K | CIBSE DHDG Table 3.4 |
Door Types
Door types are separated by category: External, Internal or Known U-Value.
Glazed Doors
When a door contains more than 60% glazing, it should be added as a window type to produce an accurate U-value.
However a window with less than 60% glazing is not a door; a door always provides a means of entry to the property.
External doors
A door that separates the property from the outside.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Door name | - | ✳️ | |
| Age band | - | ✳️ | |
| Opens to | - | ✳️ | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Table S15A |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
Internal doors
A door that separates rooms within the same property.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Door name | - | ✳️ | |
| Internal door construction | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.20 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Known U-value doors
A door that has a measured or design U-value.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Door name | - | ✳️ | |
| U-value | W/m².K | ✳️ | |
| Thermal bridging | W/m².K | CIBSE DHDG Table 3.4 |
Window Types
Window types are separated by category: External, Internal or Known U-Value.
External windows
A window that separates the property from the outside.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Window name | - | ✳️ | |
| Glazing type | - | ✳️ | |
| Frame type | - | ✳️ | |
| Age band | - | ✳️ † | |
| Year installed | - | ✳️ † | |
| U-value | W/m².K | ❌ | RdSAP 9.94 Table S14 |
| Thermal bridging | W/m².K | ❌ | RdSAP 9.94 Table S13 |
† only required for double glazed u-PVC windows
Internal windows
A window or glass partition that separates rooms within the same property.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Window name | - | ✳️ | |
| Internal glazing type | - | ✳️ | |
| U-value | W/m².K | ❌ | CIBSE DHDG Table 3.20 |
| Thermal bridging | W/m².K | ❌ | CIBSE DHDG Table 3.4 |
Known U-value windows
A window that has a measured or design U-value.
| Field Name | Unit | Required | Default Data Source |
|---|---|---|---|
| Window name | - | ✳️ | |
| U-value | W/m².K | ✳️ | |
| Thermal bridging | W/m².K | CIBSE DHDG Table 3.4 |