We've implemented a new floor U-value calculator on the fabric page over the last few months and we've finally turned it on for all our users.

As you may know, calculating the thermal transmittance of a floor is complex, as it depends on the floor's construction and exposed perimeter. The previous calculator left a lot to be desired in terms of managing this complexity, and asked for information such as soil type which is rarely available. As a result, we've rewritten it from scratch and simplified it.

The old calculator was a separate tool and was not integrated into the fabric elements page. The new calculator is a first-class section of the fabric model. You enter data for it in the same way as you do for other elements:

This means that all the data you enter is saved as part of the floor. This is another difference with the old calculator, which didn't save calculator inputs.

The input of floor layer materials is also more intuitive and robust. And unlike the previous verison, errors or warnings are shown to the user; this could be due to missing data or if there are problems using the data entered.

As ever, we welcome feedback on this new feature, so please let us know if you have queries or suggestions for improvement.