How to do a simple first cut energy calculation for a new build

[Norbert]

Our planning application has been filed. Thus I know the exact dimensions of the thermal envelope, plus all windows and doors.

I have quotes from two timber frame manufacturers with options for various U values and target airtightness. I have typical U values for triple glazed windows.

The house may or may not be to Passivhouse standard, we have yet to decide. However we will not go down the certification route.

 

What I need now is a first cut estimate of the energy demand of the house once completed. Right now I have no idea what the difference would be of a TF of U value 1.4, vs. say U 1.1 ?  Is it worth paying the extra?. What would the pay back period be? What size HP would be needed. Do I need A2W  and UFH, or would A2A be better ??

 

To get to grips with this I feel I need to get a spreadsheet together with all the calcs in so I can play around with the numbers.

 

To save me the effort of starting with a blank spreadsheet, does anyone know of a template and guidance to put something together?

 

I guess at some point I will need a professional SAP calc done, but I would like to progress a DIY approach for now.

 

[Conor]

Search here for Jeremy Harris' heat loss calculator. Not used it myself (Architect used PHPP) but people here say it's spot on.

[Norbert]

Great, found it, this is exactly what I wanted.