Hi
I am fairly new to IES and have been testing the software with simple models to produce EPC's England.
With the model I have build if I run an SBEM - EPC calc and an APACHE EPC calc the I get a significantly better result in APACHE EPC. C rating as opposed to G Rating in SBEM Calc.
Can anyone tell me why this is - I am sure my clients would want me to do the calc using Apache!! rather than SBEM
Different EPC Ratings for Same Model
Re: Different EPC Ratings for Same Model
SBEM and the ApacheSim methods will usually produce different results - this is because SBEM carries out a steady state calculation using monthly, average weather data and the ApacheSim method tool uses hourly, real weather data to perform a dynamic thermal simulation.
Did you make changes to the inputs when switching between SBEM & DSM? If not then you should have as DSM requires some different inputs and usually different models/geometry.
SBEM Systems only allow Heating/Solar water heating to be set whereas DSM Systems requires Heating/Cooling/Hot water/Solar Water Heating/Aux energy/Air supply/Control.
DSM require Lighting Power density W/m2/(100 lux) whereas SBEM uses lamp information and total wattage (W/m2).
DSM allows the user to link to Suncast to take into account local shading devices. Local Shading is ignored by SBEM.
DSM treats void spaces differently compared to SBEM. This can mean you need very different models for DSM & SBEM, there is very specific guidance for modelling unconditioned or indirectly heated spaces when using SBEM.
Did you make changes to the inputs when switching between SBEM & DSM? If not then you should have as DSM requires some different inputs and usually different models/geometry.
SBEM Systems only allow Heating/Solar water heating to be set whereas DSM Systems requires Heating/Cooling/Hot water/Solar Water Heating/Aux energy/Air supply/Control.
DSM require Lighting Power density W/m2/(100 lux) whereas SBEM uses lamp information and total wattage (W/m2).
DSM allows the user to link to Suncast to take into account local shading devices. Local Shading is ignored by SBEM.
DSM treats void spaces differently compared to SBEM. This can mean you need very different models for DSM & SBEM, there is very specific guidance for modelling unconditioned or indirectly heated spaces when using SBEM.
Re: Different EPC Ratings for Same Model
The variation in compliance methods and tools is interesting and is actually something I am researching for an MSc project. As part of my project I would like to try and gauge industry opinion and experience of differing results.
I have put together a very short opinion poll which would be great if you could complete. The survey is very brief and is available at the link below. Your time and help is much appreciated, thank you!
https://www.surveymonkey.com/s/D7NTC56
I have put together a very short opinion poll which would be great if you could complete. The survey is very brief and is available at the link below. Your time and help is much appreciated, thank you!
https://www.surveymonkey.com/s/D7NTC56