Page 27 - Designing for Zero Carbon-Volume 2_Case Studies of All-Electric Multifamily Residential Buildings

IVY SENIOR APARTMENTS
CASE STUDY NO. 1
Building Envelope – Airtightness
No special measures were taken to ensure airtightness other than conventional details to reduce air infiltration heat losses. No blower door test7 was used to measure airtightness and establish a benchmark number (ACH50).
Heating, Ventilating and Cooling Systems
A ductless mini-split system is used for space conditioning in the apartments. There is an outdoor
unit located directly overhead on the roof, which is the condenser part of the heating/cooling
7 For a discussion of this method of testing airtightness in buildings, see p. 12, Zero Net Energy Case Study Homes - Volume 1, available as a free PDF at https://calbem.ibpsa.us/wp-content/ uploads/2020/04/ZNE-Case-Study-Homes-Volume-1.pdf. See also https://www.energy.gov/en- ergysaver/blower-door-tests.
ROOF-MOUNTED OUTDOOR NON-VRF CONDENSING UNIT
AIR INTAKE
HIGH WALL-MOUNTED FAN COIL UNIT
(Left) Equipment diagram for the ductless mini-split heat pump system used for heating and cooling individual apart- ments.
Designing for Zero Carbon: Volume 2
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AIR OUTLET TO ROOM