This CIR is in reference to ventilation design for a mid-rise residential building in New England. There is a central corridor on each floor of the building, with residential unit entry doors on both sides of the central corridor. All residential unit kitchens include resident-controlled 100 cfm exhaust fans, ducted to the building exterior. 1. At the entry door from the central corridor to most of the residential units, a small entryway exists that is permanently open to the unit kitchen (opening to the kitchen is at least as large as a standard doorway, but no door exists, so there is no way to physically separate the spaces). In some residential units, a portion of the entryway floor space (typically 3 square feet - 8 square feet of floor space) is more than 8 m from a window-wall. In these cases, since the entryway is permanently open to the kitchen, can the unit entryway be considered part of the kitchen, and thus meet the requirements of ASHRAE 62.1-2004 through the inclusion of the kitchen exhaust fan? 2. A minority of residential units in the building (8%) include entry corridors, rather than small entryways, and a portion of the floor space of those entry corridors is greater than 8 meters from a window wall. In those cases, the unit entry corridors will be mechanically ventilated by delivering ducted air from a continuously running 100% fresh-air common-area corridor make-up air HVAC system to the residential unit entry corridors. Can we consider the portions of the entry corridors that are within 8m of the window walls to be mechanically ventilated, and thus base the amount of air delivered to the entry corridors on a minimum of 0.35 ACH for only the portion of the entry corridors that are more than 8 m away from a window wall?
The applicant is requesting clarifications on the application of ASHRAE 62.1-2004 for mid-rise residential building in New England. This is a two part CIR and the ruling is provided to address each of those parts respectively. 1. For kitchen areas please refer to Table E-2 in ASHRAE 62.1-2004. This building would be considered mechanically ventilated as per the information provided in the CIR and based on the 100 CFM manually controlled kitchen exhaust. Areas not within 8 m of operable windows must be provided with 0.35 ACH of the floor area of outside air. The applicant may account for the additional outside air in the kitchen exhaust and increase the kitchen exhaust volumes. 2. Yes. The spaces could be considered part of the entry corridor as long as those spaces meet the requirements for minimum outside air provided (0.35 ACH for the applicable floor area and not less than 15 CFM per person in the unit). This ruling is completely dependent on the applicant meeting all the other requirements of ASHRAE 62.1-2004 sections 4 through 7 and Appendix E. In addition to the 100 CFM exhaust, the applicant has to provide minimum exhaust flow rates as per table E-2. It would be helpful to please provide the following with your LEED Submittal to ensure that the review team has a clear picture of the ventilation air flows: 1. Line drawing schematic for the ventilation air flows in the project. 2. Calculations clearly outlining the spaces that qualify under the 0.35 ACH rule versus areas that qualify under section 5.1 or the 100 CFM exhaust rates. 3. Floor plans for a typical floor with the components of the ventilation system clearly marked and highlighted.