Dear All,

We have a residential project with hybrid heating source (gas+electric) to
condition the dwelling and corridor spaces. There are few electric heaters
serving stairwells and storage spaces. As per exception 'e' of section
G3.1.1, ASHRAE 90.1-2010, the thermal zones designed for heating only
systems in the proposed design, serving storage rooms, stairwells etc. and
not exhausting or transferring air from mechanically cooled thermal zones
in the proposed design shall use system 9 or 10 in the baseline building
design.

The query is whether the selection of system 9 or 10 is based on building
heating source (hybrid in this case) or as per unit heater's heating source
(electric).

Thank you.

Regards,

Mayank Bhatnagar

Senior Project Manager
*Environmental Design Solutions Pvt. Ltd. [EDS]*
D - 1/25
Vasant Vihar
New Delhi - 110057
India