Design SAP/New Build EPC

Kelly & Co Maghera

To comply with the current Building Regulations all new dwellings are required to have a SAP (TER/DER) calculation which should be carried out before construction commences.

On completion the SAP is re-calculated using the pressure test results (if applicable) and the details of the actual boiler used. SAP 2009 was introduced on the 31st October 2012.

This then provides the information which is included in the Energy Performance Certificate. This calculation introduced the TER/DER values where the TER is the Target Carbon Dioxide Emission Rate, which is calculated by the SAP software. The DER is the Dwelling Carbon Emission Rate calculated on the proposed design (which should be based on the current Part L/F of the Building Regulations).

Buildings subject to Part F 2006 and submitted approval after 30th September 2008 must have a TER/DER submitted to district councils at design stage. The DER must not exceed the calculated TER. When the building is completed the TER and DER on completion must be submitted to building control not more than 5 days after completion to demonstrate that the target has been met. The only exception to this is where the dwellings are created by the conversion of an existing building.

For new dwellings the standard U-values for the thermal elements are only a guide because there are so many other factors that affect the TER/DER figures. In most cases these U-values will have to be bettered (sometimes considerably) in order for the dwelling to achieve a TER/DER pass.

The following is a list of items which are now included in the SAP calculations and have the most effect on the TER/DER ratings:

  • Orientation of the dwelling
  • Area of glazing - solar gain
  • Ventilation
  • Thermal Bridging and Air Leakage - Pressure Test
  • Energy Efficient Lighting
  • Use of green energy (geothermal and solar)
  • Heating Controls and Secondary Heating (wood burning stoves)
  • Design & As Built SAP Calculations

The SAP calculation tool allows the designer a high degree of flexibility in deciding how to achieve the required energy target. However, the Approved Document does set certain limits. These include:

  • Limiting U-values
  • A limit of 10 m3/m2/h at 50 Pa for air permeability
  • Central heating boilers must be class A or B (at least 86% efficient)
  • Secondary heating must have a minimum of 37% efficiency
  • Energy efficient lighting in at least a quarter of light fittings

Ways To Reduce Bills

  • Using low energy saving light bulbs can save £5 - £10 per year on each light 12 times longer life, 80% less energy
  • Turn off lights and do not leave appliances on standby e.g. Television
  • Insulating your hot water tank can save £10 per year and reduce heat loss by 30%

The cost of insulating the tank can be recovered in 1 year.

  • Make sure hot water is not too hot - set thermostat at 60 degrees Celsius
  • By draught proofing your home, you can save £35 per year
  • Save £50 per year by having heating controls installed in your home
  • Save £300 per year with wall insulation

Further Ways To Reduce Bills

If you have solid walls you can either insulate them with external or internal insulation, saving you around £300 a year on your energy bills and can improve efficiency by 30%

  • Have your windows doubleglazed and save £40 per year

Fitting double glazed windows will save money and cost recovered in 5 years.

  • You can insulate your loft - 250mm can improve efficiency by 30% and save £180 per year

You will reduce your bills and save energy by insulating your loft and there may be energy saving grants to pay for part of the costs.

Quotation Service

Request an Energy Performance Certificate Assessment Quote to allow us to give you an accurate quote please fill in the form below:

Booking Line: 028 796 44344


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