I haven’t yet seen a sensitivity analysis performed for passive solar heating in the north American designs. Mark Siddall wrote in response to article by Martin Holladay, on the subject of Passivhaus Windows:

NOTE: Value engineering may suggest in some climates / economic conditions (such as those in the UK) that it is more cost effective to specify a better glazing U-value. The result being that the requirements for the opaque building fabric becomes less onerous.

I just wished to highlight a useful little comparison table which formed a part of a ‘Sustainable Energy Authority of Ireland’ document named, Passive homes, GUIDELINES FOR THE DESIGN AND CONSTRUCTION OF PASSIVE HOUSE DWELLINGS IN IRELAND.

See table 3, on page 12 of the document for a useful sensitivity analysis performed by MosArt designer and builders. If I have time, I will take the opportunity to practice my R-value conversion skills and translate the table into Imperial for the benefit of north American readers. But feel free to use the simple conversion factors that Martin Holladay provided to me recently. Comments as always are very welcome, and I thought it was worth creating this ‘question’ in order to highlight the relevance of Mark Siddall’s comment on the passive windows blog.

http://www.seai.ie/Renewables/Renewable_Energy_for_the_Homeowner/SEI_Passive_House_A4.pdf