SAPS REGULATIONS
The government has introduced regulations to make both new and existing buildings more energy efficient. The regulations are intended to reduce carbon emissions associated with the use of fuel in existing homes by 0.6 million tonnes by 2010.
New Dwellings
All new dwellings require a calculation to demonstrate compliance with the current building regulations. For new buildings this is carried out using a government established Standard Assessment Procedure. (SAP).
Planning applications to building control must be accompanied by such a SAP calculation carried out by a qualified person in order to proceed.
Extensions & Alterations
Extensions and changes in use are approached in one of three ways.
- Elemental compliance using the following TABLE
U-values for thermal elements {W/(m².K)} |
Element |
(a)
New elements
(in an extension or
change of use) |
(b)
Replacement elements
(in an existing dwelling) |
| Wall |
0.30 |
0.35 (*) |
Pitched roof (horizontal
insulation at ceiling level) |
0.16 |
0.16 |
Pitched roof (inclined
insulation at rafter level) |
0.20 |
0.20 |
Flat roof or roof with integral
inclined insulation |
0.20 |
0.25 |
| Floors (*) |
0.22 |
0.25 (*) |
Notes –
(*) Where meeting the above standards would cause a significant (5%) reduction in
floor area or cause problems in relation to adjoining floor levels these values may
be exceeded provided that compensating provisions are made. |
No SAP Calculation required
- Calculated Trade Off
Limiting U-values {W/(m².K)}
|
Element |
(a)
Area-weighted average
U-value |
(b)
Maximum U-value |
| Wall |
0.35 |
0.70 |
| Floor |
0.25 |
0.70 |
| Roof |
0.25 |
0.35 |
Windows, roof windows (*),
rooflights (*) and doors |
2.20 |
3.30 |
Notes –
(*)Where a roof window or rooflight has been assessed in a plane other than the
vertical, the U-value shall be modified by making a U-value adjustment in
accordance with BR 443: “Conventions for U-value calculations”. |
No SAP Calculation required
If the area of openings is more than 25% of the floor area then the total heat loss from the extension can be calculated.
If this can be shown to be equal to or less than a notional extension where the area of openings is 25% of the floor area then the extension complies.
A Notional Extension is one where the areas and u values are the minimum standards shown in the TABLE above
- Equivalent Carbon Target Approach
A SAP calculation is required to demonstrate compliance by this method
This allows any improvements in the existing part of the dwelling to be added to the standards achieved in the extension in order to meet the standards required in the TABLE shown above.
At EBSNI we carry out any of these calculations promptly at your request. | 
