I am running an L2A calculation for a warehouse with offices and trying to match a BRUKL report produced using IES.
The problem I am having is that the Alpha Value we are getting is at least 30 times that of the IES model hence giving unrealistic heating figures. The warehouse has a steel/insulation/steel composite roof and wall panel make up which is what I guess is causing the problem.
My question however is why is the alpha value is so much higher in Hevacomp??
Hi Tony
There may some small differences due to the different calculation methods - Design Database/PartL uses the SBEM calculation engine, and IES is a design simulation. I would expect the results to be in the same ball park, however.Any large differences between results will be due to the input data not matching. Please see this document for an explanation of Alpha values. You should also note that with the construction you have specified, the SBEM calculation engine will be considering these surfaces to be steel clad.
One other area you should consider is the data reflection reports - these will highlight where your input data differs.Regards,
Duncan Brown