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Directions - In order to determine the makeup air, Table 501.3.1 must be filled out (see below). For most new installations, column A <br />will be appropriate, however, if atmospherically vented appliances or solid fuel appliances are installed, use the appropriate column. <br />For existing dwellings, see IMC 501.3.3. Please note, if the makeup air quantity is negative, no additional makeup air will be re- <br />quired for ventilation, if the value is positive refer to Table 501.3.2 and size the opening. Transfer the cfm, size of opening and type <br />(round, rectangular, flex or rigid) to the last line of section D. The make-up air supply must be installed per IMC 501.3.2.3. <br />Table 501.3.1 <br />PROCEDURE TO DETERMINE MAKEUP AIR QUANITY FOR EXHAUST EQUIPMENT IN DWELLINGS <br />(Additional combustion air will be required for combustion appliances, see KAIR method for calculations) <br />One or multiple power <br />One or multiple fan- <br />One atmospherically vent <br />Multiple atmospherical - <br />vent or direct vent ap- <br />assisted appliances and <br />gas or oil appliance or <br />ly vented gas or oil <br />pliances or no combus- <br />power vent or direct vent <br />one solid fuel appliance <br />appliances or solid fuel <br />tion appliances <br />appliances <br />appliances <br />Column C <br />Column D <br />Column A <br />Column B <br />0.15 <br />0.09 <br />0.06 <br />0.03 <br />a) pressure factor <br />(cfm/sf) <br />b) conditioned floor area,(sf) (including <br />5960 <br />unfinished basements) <br />Estimated House Infiltration (cfm): [la� <br />x lb] <br />2. Exhaust Capacity <br />a) continuous exhaust -only ventilation <br />system (cfm); (not applicable to ba- <br />PIJ <br />lanced ventilation systems such as <br />HRV) <br />b) clothes dryer (cfm) <br />135 <br />135 <br />135 <br />135 <br />c) 80% of largest exhaust rating (cfm); <br />Kitchen hood typically <br />(not applicable if recirculating system <br />or if powered makeup air is electrically <br />interlocked and match to exhaust) <br />d) 80% of next largest exhaust rating <br />(cfm); bath fan typically <br />Not <br />(not applicable if recirculating system <br />Applicable <br />or if powered makeup air is electrically <br />interlocked and matched to exhaust) <br />Total Exhaust Capacity (cfm); <br />[2a + 2b +2c + 2d] <br />3.Makeup Air Quantity (cfm) <br />a) total exhaust capacity (from above) <br />a) <br />b) estimated house infiltration (from <br />above) <br />Makeup Air Quantity (cfm); <br />(if value is negative, no makeup air is <br />needed) <br />4. For makeup Air Opening Sizing, refer <br />to Table 501.4.2 <br />A. Use this column if there are other than fan -assisted or atmospherically vented gas or oil appliance or if there are no combustion appliances. (Power vent <br />and direct vent appliances may be used.) <br />B. Use this column if there is one fan -assisted appliance per venting system. (Appliances other than atmospherically vented appliances may also be in- <br />cluded.) <br />C. Use this column if there is one atmospherically vented (other than fan -assisted) gas or oil appliance per venting system or one solid fuel appliance. <br />D. Use this column if there are multiple atmospherically vented gas or oil appliances using a common vent or if there are atmospherically vented gas or oil <br />appliances and solid fuel appliances. <br />Page 3 of 6 <br />