22-429 Design method I | Aurora City Code

Sec. 22-429. Design method I.

(a) Generally. Under this article, this method requires the designer or architect to follow the construction requirements for all exterior façade elements as listed in the tables below.

Table 22-1. Residential construction requirements in the NID, NIBA, and LDN 55¹
Façade Element	Minimum Requirement
Exterior walls
Structural	2" by 4" wood or metal studs
Insulation	R-15 bat insulation or full cavity fill
Interior gypsum	Blown cellulose
Exterior applications	1-layer of ½" or ⅝" gypsum 7/16" OSB or plywood and stucco, siding, brick or stone
Basement walls	Basements are excluded, as long as basement windows and sliding glass doors have minimum STC ratings of 30.
Exterior floors	Normal construction, except for full joist fill insulation
Roof and exterior ceilings	Minimum attic insulation shall be R-38. Vaulted roof/ceiling structures are allowed, coffered ceilings are acceptable. For vaulted ceilings the minimum joist or truss depth is 14 inches. Use of vaulted ceilings increases required STC rating of windows above those listed.
Doors
Exterior swing doors	Solid core doors with jamb seals and sweeps, glazing in doors shall have minimum STC rating of 30
Sliding glass doors	Minimum STC rating of 30
Windows	Minimum STC rating of 30
HVAC and appliance venting	Shall be as specified in sec. 22-433

1Minimum 25 OITL decibels

2Minimum 30 OITL decibels

Table 22-2. Residential construction requirements in SNID and LDN 65
Façade Element	Minimum Requirement
Exterior walls
Structural	2" by 6" wood or metal studs
Insulation	R-19 BAT insulation or full cavity fill blown cellulose
Interior gypsum	2-layers of ½" or ⅝" gypsum
Exterior applications	2-layers of ½" or ⅝" gypsum 7/16" OSB or plywood and stucco, siding, brick or stone
Basement walls	Basements are excluded, as long as basement windows and sliding glass doors have minimum STC ratings of 34.
Exterior floors	Normal construction, except for full joist fill insulation
Roof and exterior ceilings	Minimum attic insulation shall be R-38. Joist type vaulted roof/ceiling structures are not allowed, coffered ceilings are acceptable. Truss type vaulted ceilings are allowed and shall have a minimum truss depth of 36". Use of vaulted ceilings increases required STC rating of windows above those listed.
Doors
Exterior swing doors	Solid core doors with jamb seals and sweeps, glazing in doors shall have minimum STC rating of 34
Sliding glass doors	Minimum STC rating of 34
Windows	Minimum STC rating of 34
HVAC and appliance venting	Shall be as specified in sec. 22-433

1Minimum 25 OITL decibels

2Minimum 30 OITL decibels

Table 22-3. Commercial construction requirements in LDN 65¹
Façade Element	Minimum Requirement
Exterior walls	Typical commercial construction
Roof and exterior ceilings	Typical commercial roof/ceiling construction
Doors	Typical commercial doors
Windows	If window area in a specific room is less than 20% of the total area minimum STC rating of 28, if window area in a specific room is greater than 20% of the total area minimum STC rating of 32
HVAC and appliance venting	None

1Minimum 25 OITL decibels

Table 22-4. Commercial and residential construction requirements in the CANA²
Façade Element	Minimum Requirement
Exterior walls	Typical commercial construction
Roof and exterior ceilings	Typical commercial roof/ceiling construction
Doors	Typical commercial doors
Windows	If window area in a specific room is less than 20% of the total area minimum STC rating of 30, if window area in a specific room is greater than 20% of the total area minimum STC rating of 32
HVAC and appliance venting	None

2Minimum 30 OITL decibels

(d) Construction. All exterior walls, roofs and exposed floors shall be of airtight construction. All nonlap joints shall be grouted or caulked airtight with a nonhardening, nonshrinking sealant installed in accordance with manufacturer's specifications. Any penetrations of exterior walls or roofs by pipes, ducts or conduits shall be sealed airtight as required for joints. Door and window openings in exterior walls shall be flashed all around with an approved vapor barrier and sealed to prevent air infiltration. Sill sealant shall be used to prevent air infiltration at all base plates of exterior walls. Attic and crawl space vents shall not exceed minimums specified by ordinance. Crawl space vents shall be baffled as shown in figure 22-1. See section 22-432 for building mechanical systems. (Ord. No. 2011-07, § 4, 4-11-2011; Ord. No. 2007-49, § 17, 8-27-2007; Ord. No. 2006-78, § 1(Exh. A), 1-8-2007)