Building a Deck and Preventing Water Damage

by DEJ
(Ohio)

I have a few questions about building a deck and preventing water damage. I am concerned about framing the deck, beams and how to prevent rotting of the joists, beams and decking over time.

If answers already exist in historical threads, then please direct me accordingly to another forum, or "Tech" article, on this site.

Design: 24'X24' (7' above ground). Southern Pine #2 frame.

Footers: 18" Belled-bottom ~34 - 36" below grade.

Posts: 6X6.

Ledger: (1) 2X10 secured by 5/8" Red Head Sleeve Anchors into Brick-on-Block house @ 18" to 24" O.C.

Beams: Three spans of (2) 2X10 ~8', Notched 2.75" into post and (2) 1/2" through-bolt fastening. All beams have (3) vertical rows of Ledger Lock 2.5" for added stability.

Joists: 2x6 <8' spans, all attached by Joist hangers for useable clearance below, with #10D 2.5" HDG.

Decking: Premium 5/4X6 Horizontal.

Questions:
1. I would like to flash the beams, possibly to a width sufficient to cover over the joist hangers - sort-of like a "drip-edge" to prevent water into\onto the joist hangers. I'm concerned about using a 9" galvanized flashing where H2O may simply sit on and cause rust or rotting of the underside of the decking.
1.A. I would consider simply using Silicone caulk where the 2X10's are mated to prevent rot in between the 2X10 beams or...
1.B. Considering the use of a flexible flashing, Vycor Plus*, made by Grace to flash the top of the beams and top of the posts.

2. Is a waterproofing\sealant necessary on the underside of the decking - prior to installation?

I have been advised to do so, but my decking is so saturated then I'll have to dry the boards sufficiently, and I'm not entirely sure how to dry them fast enough without laying them on the joists, which may cause far too much warping\cupping etc. and installation may become a nightmare.

3. Should I seal the top of the joists before laying the decking?

4. Anyone have experience with a product called "One Time Wood"?

5. Any advice on Ledger Board flashing. I think I know what I'm doing on this one, but it doesn't hurt to ask.