PHI has released an extensive catalogue of 600 timber frame thermal bridge calculations, plus a results file in Excel format that shows the resulting PSI values. The goal was to create a timber thermal bridge catalogue that was manufacturer independent—and which included varying construction thickness and U-values so that intermediate values could be interpolated (using the Excel file).
The catalogue is in German but there is almost no text in the main catalogue section (and Google Translate is easy to use). Most of the constructions are a bit thick compared to what is needed on projects in Aotearoa New Zealand. But there are so many details! There are lots of installs for windows and I-joist walls among other fun stuff to delight building science geeks.
These are good examples of timber constructions and of course the calculation methodology is excellent. The construction methods do differ from what is typically employed in this country, even in Passive House projects. The use of timber I-beams (hyJOISTS for example) are still not common but they deliver great improvements in wall/roof/floor thermal performance and they feature heavily in this catalogue.
So although not developed with New Zealand in mind, it is still useful to add to the handy references in a Passive House designer’s toolbox. We’ve collected all of the thermal bridge resources we have found useful and you can find them on the Sustainable Engineering website.
The shorthand naming system uses the PHI standard abbreviations. If you’re familiar with the High-Performance Construction Details Handbook (HPCD), you’ll find it quite easy to find the thermal bridge you’re after. The Excel file is a great idea but I’ve had trouble making it work. I’m keen to hear from any readers who have figured it out—please let me know.
Do note that these calculations use -10C as the outside boundary condition, compared to 0C used in the HPCD. This impacts the isotherms but the fRSI is the same, regardless of the exterior temperature, because ISO10211 has the thermal conductivity constant with temperature for a material.
The PHI catalogue is only available for iPHA members (membership is included in your PHINZ or APA membership).