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Design models can feed analysis: energy use, daylight, thermal comfort, structural behaviour, airflow, acoustics. Done well, analysis moves from an occasional report to a regular check on the design. Done badly, it runs on an export that nobody can repeat, against a design that has since changed.
Each analysis tool needs a different simplification of the design. Energy tools need closed spaces and the surfaces around them. Structural tools need members as lines with nodes, supports and loads. Daylight tools need surfaces with their materials. None needs the furniture or the door handles.
The stage 2 energy study shows the building meeting its target, and the report goes in the design file. In stage 3 the plant room grows, the glazing changes and two floors are reorganised. Nobody reruns the study. At the stage 4 compliance check, the building fails the target by a wide margin, and the façade has already been tendered.
The BEP lists the analyses, the model version each used, and what triggers a rerun (changes to glazing, fabric, spaces or plant). When the glazing changes in stage 3, the study is rerun on the new version. The shortfall shows up early, while the façade can still change.
What each analysis needs
| Analysis | Needs from the model | Common problem |
|---|---|---|
| Energy | Closed, bounded spaces; typed surfaces; location | Missing or open rooms; walls not bounding rooms |
| Daylight | Surfaces with materials; windows; surroundings | Glazing with no properties; no neighbouring buildings |
| Structural | Members, supports, loads, as an idealised model | Physical and analysis models drift apart |
| Airflow and comfort | Spaces, openings, heat sources | Simplification not agreed with the analyst |
The analyst needs the clinic for an energy study. Put your preparation steps in order.
Prepare the energy export
Put the preparation steps in order.
- 1Check every space is modelled and bounded
- 2Agree with the analyst what they need
- 3Send it with a note of what is included
- 4Export and record the model version
- 5Set the location and orientation
- 6Check surfaces and windows are typed
Key takeaways
- Each analysis needs its own simplified view of the design: spaces and surfaces for energy, members and loads for structure.
- Model spaces and room bounding correctly; most energy exports fail because rooms are missing or open.
- Record which design model version each analysis used, and rerun it after relevant changes.
- Analysis results come back as decisions in the design, not as a separate model nobody updates.
Your notes
Related tool
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