published: 12/8/2005
12 August 2005 - Feedback from the first iSBEM Beta Test
To all those who offered comments, suggestions and criticisms of SBEM.
Thank you for spending the time to try out the tool and for your helpful comments. I apologise if some of the limitations were irritating but - given the very short timescale - we thought that it was best to seek early feedback from users. Hopefully this has enabled us to focus on the issues that you see as most important.
All the comments have been considered and taken seriously, but some are easier to address than others.
I hope you will see that the second issue of SBEM (which is currently being subjected to some independent assessment before being released later in August) has taken on board a number of your suggestions and responded to some of your difficulties.
We still have a list of further issues to address before the final version in September.
We can't give a detailed explanation of what has changed, but I would like to pick up a few points that were made by several people:
- Naming convention. It is important to have a naming system that has some structure and is unambiguous. SBEM gives zones and elements names according to a particular convention. If you don't like the somewhat cryptic SBEM names, you can replace them by your own.
- Data input and graphical interfaces. I hope that you will find the new data input structure is easier to use. Our brief for the iSBEM interface is to keep it fairly basic but able to deal with the majority of buildings - in other words, a graphical interface would be beyond the brief. The expectation is that SBEM will also be embedded in commercial software that has its own, perhaps more visual, interfaces.
- Calculations. The main changes are:
- Daylighting. The new issue will have daylighting algorithms based on the draft CEN Standard, but extending it in several areas (for example to include rooflights
- A new monthly infiltration algorithm based on the draft CEN Standard,
- The monthly heat gain and loss calculation now explicitly accounts for the thermal capacity of the construction in accordance with the draft CEN Standard.
- There is now a choice of three different sets of weather data.
- Other upgrades in the pipeline include DHW systems and radiant heating.
- Notional Building. The rather arbitrary assumptions in the first version have now been replaced by proper ones. The notional building is automatically calculated from the information given about the actual building, so the user will not normally need to see the details.
- Controls. You will see that daylight controls options are now well-represented. We are looking at the various suggestions that have been made for additional HVAC controls options and expect to include many of them
