Hello,

We’re currently involved in the LEED Certification of a new building to be built in Portugal. In what relates with pipping insulation, we have a doubt related with one of the notes included in Table 6.8.3-1 Minimum Piping Insulation Thickness Heating and Hot Water Systems from ASHRAE 90.1:2010.

Note d. states the following: “for direct-buried heating and hot-water systems piping, reduction of these thickness by 40 mm shall be permitted but not to thicknesses below 25 mm”.

The question is: Which systems does the note above refer to?

                Option 1: "direct-buried heating systems piping" and "hot-water systems piping", OR

                Option 2: "direct-buried heating systems piping" and "direct-buried systems hot-water piping".

Best regards,