Hi all,
As per ASHRAE 90.1-2010: 5.4.1 Insulation. Where insulation is required in Section 5.5 or 5.6, it shall comply with the requirements found in Sections 5.8.1.1 through 5.8.1.9.
I understand that insulation is not mandatory but what does this mean for projects targeting a LEED rating and therefore only complying with the mandatory requirements? Can it be ignored?
Or does it mean that all installed insulation must comply with the requirements in Sections 5.8.1.1 through 5.8.1.9?
Or does it mean that if you are following 5.5 Prescriptive Building Envelope Option or 5.6 Building Envelope Trade-Off Option then you must comply with the requirements in Sections 5.8.1.1 through 5.8.1.9?
Thank you
Ayesha Nakhwa
December 14, 2023 - 1:26 am
Since posting this question I found this information in the Standard 90.1 User's manual:
Compliance with the standard requires that the mandatory provisions be satisfied in all cases. Section 5.4 contains the mandatory requirements for the building envelope. The mandatory requirements include insulation installation requirements (applicable to the Prescriptive Building Envelope Option and Building Envelope Trade-Off Options only) and requirements for reducing air leakage.
This suggests to me that insulation installation requirements must only be complied with for the Prescriptive Building Envelope Option and Building Envelope Trade-Off Options only.
Am I understabding this correctly?
Marcus Sheffer
LEED Fellow7group / Energy Opportunities
LEEDuser Expert
5898 thumbs up
December 14, 2023 - 10:53 am
LEED requires compliance with all mandatory provisions. The amount or level of insulation is not mandatory, this is a prescriptive requirement.
There are insulation characteristics and installation requirements in Sections 5.8.1.1 through 5.8.1.9 that are referenced in Section 5.4 so they are mandatory.
What you are looking at are code compliance options that don't really come into play for LEED.