402.1.5.1 Direct Siding Attachment

Siding installed directly over foam sheathing without separation by an air space shall comply with Table 402.1.5.1 in regard to minimum fastening requirements and maximum foam sheathing thickness limitations to support siding dead load. The siding fastener and siding installation shall otherwise comply with the Residential Code of New York State, Section 703.4 and Table R703.4, and in no case shall result in a less stringent fastening requirement than required by the Residential Code of New York State, Section R703.4 or the manufacturer's installation instructions for the specific siding material used.

Exception: For exterior insulation and finish systems, refer to the Residential Code of New York State, Section 703.9.

TABLE 402.1.5.1 SIDING MINIMUM FASTENING REQUIREMENTS FOR DIRECT SIDING ATTACHMENT OVER FOAM PLASTIC SHEATHING TO SUPPORT SIDING WEIGHT¹

SIDING FASTENER THROUGH FOAM SHEATHING INTO:	SIDING FASTENER TYPE AND MINIMUM SIZE2	SIDING FASTENER VERTICAL SPACING (INCHES)	MAXIMUM FOAM SHEATHING THICKNESS (INCHES)
			16"oc Fastener Horizontal Spacing			24"oc Fastener Horizontal Spacing
			Siding Weight:			Siding Weight:
			3 psf	11 psf	25 psf	3 psf	11 psf	25 psf
Wood Framing (minimum 11/4 inch penetration)	0.113" diameter nail	6	4	3	1	4	2	0.75
		8	4	2	0.75	4	1.5	DR
		12	4	1.5	DR	3	0.75	DR
	0.120" diameter nail	6	4	3	1.5	4	2	0.75
		8	4	2	1	4	1.5	0.5
		12	4	1.5	0.5	3	1	DR
	0.131" diameter nail	6	4	4	1.5	4	3	1
		8	4	3	1	4	2	0.75
		12	4	2	0.75	4	1	DR
Steel Framing (minimum penetration of steel thickness + 3 threads)	#8 screw into 33 mil steel or thicker	6	3	3	1.5	3	2	DR
		8	3	2	0.5	3	1.5	DR
		12	3	1.5	DR	3	0.75	DR
	#10 screw into 33 mil steel	6	4	3	2	4	3	0.5
		8	4	3	1	4	2	DR
		12	4	2	DR	3	1	DR
	#10 screw into 43 mil steel or thicker	6	4	4	3	4	4	2
		8	4	4	2	4	3	1.5
		12	4	3	1.5	4	3	DR

For SI: 1 inch = 25.4 mm; 1 pound per square foot (psf) = 0.0479 kPa.

DR = design required

1. Tabulated requirements are based on wood framing of Spruce-Pine-Fir or any wood species with a specific gravity of 0.42 or greater in accordance with AFPA/NDS and minimum 33 ksi steel for 33 mil and 43 mil steel and 50 ksi steel for 54 mil steel or thicker.

2. Nail fasteners shall comply with ASTM F1667, except nail length shall be permitted to exceed ASTM F1667 standard lengths. Self-drilling tapping screw fasteners for connection of siding to steel framing shall comply with the requirements of AISI S230. Specified fasteners in accordance with Residential Code of New York State, Section R703.4, or the siding manufacturer's approved installation instructions shall meet all other requirements in ASTM F1667, AISI S230 or be otherwise approved for the intended application.