Flashing on top of a joist?

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drewdin

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I have been reading that water can accumulate between composite/PVC decking and wood framing, the composite/PVC causes the water from drying fast and can rot joists faster.

Would it be worth using a flashing tap on top of the joists? Should I use metal or rubber flashing? I saw that asphalt flashing can cause discoloration of the PVC and composite products.

What have you used if any?

Thanks
 
I think it's potentially an issue on a deck that doesn't get a lot of sun. Mine was on the north side of my house and I had some left over ice shield that I used on mine. I had a few feet of decking on before before I realized I could see some of the white lettering between the deck boards. After that I made sure to use just black pieces.
If you don't want to use that you could also brush on some good water seal on the tops of the joists.
 
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Ice and water shield is a great choice as it will seal to an extent around nail or fastener penetrations.
 
I was also reading to put a sealer on the endgrain of the PT, is that overkill? if so i'm in
 
A quart of end grain treatment is plenty for a deck.
2" wide tar paper on top of the joists all hangers fasteners and flashing are galvanized steel
 
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