Sample House

 

Weights of Building Materials

 

Density of S-P-F versus DF-L

Assume 15% moisture content for both species.  

Specific gravity G for DF-L = 0.50, and specific gravity G for S-P-F = 0.42.  (NDS table 11.3.2A)

Density = 62.4 G (1 + MC/100) / (1 + G x 0.009 x MC)  (NDS Supplement section 3.1.3)

• Density of DF-L = 62.4 x 0.50 (1 + 15/100) / (1 + 0.50 x 0.009 x 15) = 33.61 lb/ft³  
• Density of S-P-F = 62.4 x 0.42 (1 + 15/100) / (1 + 0.42 x 0.009 x 15) = 28.52 lb/ft³  
• Ratio of S-P-F to DF-L = 28.52 / 33.61 = 0.8486

Weight of DF-L  (textbook appendix A)

• 2x4 @ 16" OC = 0.9 psf 
• 2x6 @ 16" OC = 1.4 psf
• 2x8 @ 16" OC = 1.9 psf
• 2x10 @ 16" OC = 2.4 psf

Weight of S-P-F

• 2x4 @ 16" OC = 0.9 x 0.8486 = 0.7637 psf
• 2x6 @ 16" OC = 1.4 x 0.8486 = 1.188 psf
• 2x8 @ 16" OC = 1.9 x 0.8486 = 1.6123 psf
• 2x10 @ 16" OC = 2.4 x 0.8486 = 2.037 psf

 

Other materials  (textbook appendix B unless otherwise noted)

Material	Weight, psf
plywood, per in. of thickness	3.0
30-lb roofing felt  (source)	0.2
asphalt shingles	2.0
fiberglass, loose, per in. of thickness	0.5
hardwood, 1 in. nominal	4.0
gypsum wallboard, per in. of thickness	5.0
vinyl  (estimated)	0.5