Installer nailed through wooden soffits

First post here. I live in a home that was built in the 1920’s. When installing new shingles, the roofer nailed through the wooden soffits and now some of them are splitting/deteriorating. Someone told me that the roofer should have used a shorter nail for nailing the shingles to the decking in those areas. Is that true? A good portion of the nails are protruding through the soffits. I will probably have to replace a good portion of the soffits. Any advice is appreciated. Thanks for your help.

for the shingles to be fastened properly, the nails must protrude the back side of the decking by at least 1/4". if a nail only goes into a 1/2" thick piece of decking half way (1/4" or less) how do you expect it to hold the shingle down if ANY wind comes along?

yes, for cosmetic purposes, shorter nails CAN be placed in those areas. but i wont do it on any of my jobs. i just explain to the customer that the nails will protrude in the soffits, otherwise they have no warranty.

What is the deck composed of-1/2" plywood over original 3/4" boards?

As a rule, open soffits are composed of 3/4" pine and it’s not necessary to use nails that protrude through the boards. That’s a plywood requirement since plywood has little grip.

Of course, the OP hasn’t mentioned what his soffits are composed of at this point.

(Plank roof decks do not get nailed so the nails protrue into the attic space. That’s a new thing you see with plywood decks.)

good point. i was thinking plywood.