post length post size code
1000 3'-3" 75 x 75 SPR 100
1050 3'-6" 100 x 100 SPR 105
1200 4'-0" 100 x 100 SPR 120
1350 4'-6" 100 x 100 SPR 135
1200 4'-0" 100 x 75 SPR 120 3


In exposed windy situations or for high fences 100 x 100 spur posts should be used.