Nail and Screw Pull-Out
Typical pull-out resistance by fastener and species.
Example
You enter
- Fastener type nail
- Fastener size 16d_common
- Wood species DF-L
- Penetration into receiving member (in) 1.5
You get
- Withdrawal per inch 39.5 lb/in
- Total withdrawal 59.3 lb
- Specific gravity 0.5
- Diameter (in) 0.162
Checked against published worked examples from: International Staple, Nail and Tool Association (ISANTA).
Details, formula, and sources
Formula or tableWithdrawal capacity per inch of penetration: nails W = 1380 × G^2.5 × D; wood screws W = 2850 × G^2 × D (NDS 12.2); G is wood specific gravity, D is fastener shank diameter; lag screws are not modeled.
Source and editionAWC NDS-2018 (National Design Specification for Wood Construction). Chapter 12 (dowel-type fastener withdrawal).
Free accessFree at awc.org/codes-standards.
What governsEstimate. AHJ and licensed structural engineer govern.
API field namesfastener_type, fastener_size, species, penetration_in, withdrawal_per_inch_lb, total_withdrawal_lb, specific_gravity, diameter_in
- Specific gravity table data/construction/lumber-properties.json keyed to speciesAWC NDS-2018