The Nails Needed for Roof Sheathing calculator computes the approximate number of nails needed to nail 4x8 sheets to trusses or rafters on a roof based on the dimensions of the roof, spacing of nails on the edges and field of the 4x8, and whether blocking or clips are use.
INSTRUCTION: Choose units and enter the following:
- (L) Ridge Length
- (S) Roof Span
- (oH) Overhang
- (P) Roof Pitch (rise over run)
- (eS) Edge Spacing of nails (see below)
- (fS) Field Spacing of nails (see below)
- (BC) Choose Blocking or Clips
Number of Nails (N): The calculator returns the number of nails needed. A typical box of nails may have 5,000 nails. If clips are used, it also provides an estimate on the number of clips needed.
Special thanks to Larry Hunt for technical guidance on this calculator.
This calculator answers the following questions:
- How many nails do I need for my pneumatic nail gun?
- How many nails do I need to put plywood or OSB on rafters or trusses?
4x8 sheets on a roof
Using the length, width and pitch, the calculator computes the square footage of the roof. It then computes the number of 4x8 sheets required to cover the roof. Modern construction techniques take advantage of the time saving achieved through using pneumatic nail guns. Nail guns like the RHF9021NS Air Framing Nailer from BN Products are used to rapidly nail sheeting to roof trusses saving time and money. 
Blocking or Clips
The number of nails that will be needed are determined by the pattern of nails. There are two different patterns for nails based on whether there is blocking that allows continuous edges or if clips (see picture) are used. The diagram shows the two patterns.
Roof Types
