pergo underlayment

[Kaizen]

i have a large room i'm putting pergo laminate in. Not ideal but i took up 5 layers of floor 20 years ago to get down to the 120 year old doug fir floor and i have to get it covered. I will be patching some sections with 1x material and as i have the height i'm going to put down 1/2 osb to bridge any gaps as well as level out the floor as i'm sure it has some waves in it. My question is what fastener should i use? I have the doug fir t&g with 3/4 pine under that. Should I just sink some deck screws and call it a day or use framing nails every x inches? I am fine with not getting into the joists. I also have ring shank siding nailer with 2" nails.

 

[PCustoms]

What's wrong with the Doug fir, will it ever be salvageable?

I'd use a T&G sheet, plenty of adhesive and fasteners (screws) through to the joist if possible. Otherwise ring shanks may be OK

 

[Kaizen]

What's wrong with the Doug fir, will it ever be salvageable?

I'd use a T&G sheet, plenty of adhesive and fasteners (screws) through to the joist if possible. Otherwise ring shanks may be OK

I've always dreamed of patching it in but its an odd size so i would need to mill it myself as well as it has thick probably lead paint. The previous century of floors all were nailed down to it so besides the nail holes and damage it has a bad habit of expelling sharp metal every season as it swells and contracts.
Its stable enough that i can use it as a base but not worth repairing. Thanks I think i'll use a combination depending on what nails i have. I just ordered finish nails for some trim and just about choked on the price.