Dear recipients,

Starting to read ASHRAE 90.1 with focus on skylights, I'm not sure that I read the standard correctly. Can anyone here help?

I'm reading ASHRAE 90.1 -2007 (SI Edition) and am looking for the building envelope requirements for Climatic Zone 5. As I read table 5.5.5 (assuming a nonresidential building), the skylight can have a U-value (of the assembly) up to 6.64 assuming it is made of glass However this doesn't give any meaning - since a U-value that high is almost equivalent to the surface resistance factors (and nothing from the glazing/gases etc.).

What U-value should I use for the skylights in the budget-building - assuming the building to be constructed in climatic zone 5?

Med venlig hilsen / Best regards

Claus Rudbeck