Asking for help before starting deck on EPDM

I have an existing 25 yr old 2nd story redwood deck over EPDM. The sleepers have rotted, so decking not well attached any longer. Should I bond new sleepers to the rubber or just let the new deck float. I'll probably go back with redwood decking to reduce cost. I am hoping to salvage much of existing decking by inverting the old 2 x 6 boards and perhaps cutting off split ends. Am I on track thinking of leaving the old sleepers in place and putting new ones along side? Treated or redwood for new sleepers? Attach or float? One nagging consideration on floating is that here on the lee side of the Rockies we have occasional winter winds above 125mph.Thanks for any advice from decking pros.

 

I would special order treated lumber rated for ground contact. Ordinary 2"x treated lumber is NOT treated for ground contact and is intended to spend most of it's life dry. In your situation sandwiched between the deck above and roof below the sleepers probably spend much of their life wet hence the rot.

My first thought would be to float the deck but I would check with your local building inspections dept. Your repair (important to say "repair" of some rotten sleepers) should not require permits or inspection but the inspections dept can give you good guidence of modern construction methods to deal with the occasional high winds.