> For the complete documentation index, see [llms.txt](https://docs.betterbuilding.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.betterbuilding.io/sign-up-and-plans/news-and-updates/2026/hygrothermal-modelling-updates.md).
# Hygrothermal Modelling Updates
V 1.2
Since releasing the hygrothermal wall solver and then the roof solver, where most of our effort went into verification, we have been able to finally turn to the so called 'quality of life' features that had been sitting in the backlog.
### A Visual Uplift
The wall and roof system views have been redrawn. They look more modern and are, frankly, more pleasant to stare at during a session. This does not change any results. of course, it just makes your model easier to read.
Related to this, the section view can now be toggled to a top-down view and back again. Small feature, but useful when you are trying to work out which layer is which.
### DA07 /ASHRAE 160 Defaults
All moisture settings now default to values very close to the requirements of DA07 /ASHRAE 160 for a typical wall or roof system. The details of a given project will always shift these slightly, and you should still review them. But the practical outcome is that a quick assessment run on defaults will land very close to what the National Construction Code expects.
In real terms, designing a wall or roof system and running a hygrothermal model now takes around five minutes. That used to take longer, mostly because of setup rather than solve time.
### Cleaner Results
Results have been tidied up, and the Summary Results and Inputs tabs have more options for how you view them. Every available chart now has an explanation alongside it, written with the goal of telling you what the chart is actually showing.
### Sectioned PDF reports
PDF output is now split into sections: Project, Results, Method, Inputs and Climate. You choose which go in. Early in a job you might export just Project and Results to share with a client, then produce the full report for final submission once the design settles.
The detailed report also includes more of the model inputs than it did before. If someone is reviewing your report (a certifier, a peer, a future version of you), they can confirm every requirement of the hygrothermal model has been stated without having to open the model itself.
{% file src="/files/N0sZH23RnRnR4O8nI3Rh" %}
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