If you are thinking of selling your house and don't want to be surprised by the Energy Performance Certificate which will be part of the Home Information Pack, or are just interested in reducing your home carbon emissions, you will find this computer program helpful.

Using minimal input data, this easy-to-use Home Energy Audit software calculates the energy rating and carbon emissions of the dwelling in accordance with the government's Standard Assessment Procedure (SAP 2005) Appendix S. RDsapper then checks what, if any, cost effective improvements would be appropriate to bring the dwelling up to its maximum potential environmental performance. The suggested improvements could increase the value of your home.

Click here to see a typical Environmental Performance Report.

Input data includes the following:

• Age of dwelling and any improvements.
• Construction materials and any insulation.
• Dimensions of dwelling.
• Any room-in-roof or conservatory
• Type of window glazing.
• Solar water heating.
• Heating system and method of hot water heating and fuels.
• Use of Low energy light fittings.
• Photovoltiac and other Low or Zero Carbon technologies..

When all information has been entered, the potential improvements will be shown together with indicative cost savings.

Although this software was originally written for use by trained energy assessors, it has been decided to market RDsapper as a DIY tool for homeowners. It will not produce an Energy Performance Certificate. Every effort has been taken to make the working of the software accurate and consistent with SAP 2005 Appendix S and it has been satisfactorily tested against 40 examples. The accuracy is dependent upon information to be entered correctly by the user! The outputs are indicative only.