Seems 1 1 4 nails are recommended.
Normal length for roofing nails.
Nails that are longer than six inches are called pikes and they are seldom used on roofs.
If you need bigger nails including pikes you may need to place a special order at the hardware store.
The roof structure is completely open and can be seen from underneath.
Will the 1 1 4 nails rust since they will be below the plywood.
For dimensional shingles being installed over a layer of existing dimensional shingles you should always use a 1 1 2 inch roofing nail.
Use only zinc coated steel or aluminum 10 12 gauge barbed deformed or smooth shank roofing nails with heads 3 8 10mm to 7 16 12mm in diameter.
Fasteners must be driven flush with the surface of the shingle.
It is outside in a yard.
Most of the nails do not come through the plywood.
The one to two inch roofing nails are suitable for most types of roof shingles.
The nails used are 1 2 3 4.
If your decking is less than 3 4 inch then a 1 1 2 inch nail will suffice.
Roofing nails should be long enough to penetrate the roofing material and go 19 mm into osb solid wood plywood or non veneer wood decking or through thickness of decking whichever is less.
The most commonly used roofing nails range from one to two inches in length.
The length of the nail is the shank and the shank can also vary.
Screw shank nails are twisted and have sharp diamond tips and they are used to securely fasten wood roofs.
Fasteners should be long enough to penetrate at least 3 4 19mm into wood decks or just through the plywood decks.