Deck replacement leads to rot

[Grump]

I keep finding things to do in the remodeling of my home. This time I wanted to replace the small deck off my back door.
http://grumpsplace.com/images/home/addition0021.JPG

I have already removed the large skirt board to the left of the deck and put house wrap and new siding in wainscot fashion up to the window, with a drip rail. I wasn't going to change any of the siding from the deck over because I want to punch the bathroom wall out to the fascia board later. That is about where the hose hangs and to the back of the house (almost 10'). I'll side that whole bath wall and then wainscot the rest.

Anyway, I had to remove as much old material as possible, in preparation for the new deck. I need to tear the old one down and get the new one up in a single day. I have dogs that use that yard and no other way to let them in and out. I wanna make it easy on myself. So, I ripped off the skirt board and found the siding under it was rotten. I removed that by cutting it off with my circular saw and prying it off, including the paper and Z-bar.

http://grumpsplace.com/images/home/addition0229c.jpg
http://grumpsplace.com/images/home/addition0218.jpg

There you see the worst of the damage (the board slanted on the bottom is just a scrap I nailed up to keep the dogs from going under the house and out to the street side). The rot does not go beyond what you see here, as far as I can tell. I dug out a lot of it with a pry bar.

A few questions:
Can I clean out the loose debris and put some kind of liquid in there to stop the rot from growing?
If I have to remove material, can I only remove the rotted areas and replace with new, even if it's only a couple of feet?
How should I "sister" in joist extensions for the bath 1' 9" punch-out (might as well do that part now)?

I also decided to change the deck a little. The deck will be brought out to just shy of the fascia board to make it a foot and a half deeper (7' 6"L X 5' 6"W instead of 4'), two steps down along the house, a 4X4' landing, one step down 90° from that and then a 8X8' deck. I will have an "L" shaped step at the front right corner, which makes for the perfect riser height to the ground.

http://grumpsplace.com/images/home/deck_plan01.gif

The lower deck will be very close to the ground at the rear right corner and I am concerned about the lumber. It snows here and that corner will prob'ly be only an inch or two off the ground. Even when it's dry, that's pretty close and I don't want it to rot out from under me.

I guess that's a lot to contemplate, but hey, you guys got nothin' better ta do. ;) I'm looking forward to your advice and suggestions.

Grump

[roger g]

At the present I live on the west coast where it is supposed to be damp all the time but in reality it is very dry in the summer which is at least 6 months. Prior to that i lived in the middle of the country where it is cold in the winter and hot and humid in the summer. In both places, wood rots. Sometimes in appeared to be poor wood quality and sometimes it was insects and sometimes it was damp. In any case it rotted in places. Never all over but in places. What I'm saying is that it will always rot quicker than you would like. Wooden decks appeared about 40 years ago and prior to that we had things called patios. Patios never rotted! Decks appeared about the same time as shag carpets. You have to protect wood. It really is that simple. That is why aluminum siding came into favour then plastic. You don't protect wood with more wood.Rot is the penalty you pay for in having the wood look.
Prtoect wood as much as you can and if you want maintenance free deck. Buy that plastic wood made from recycled plastic. It really is getting better. Exposed wood will always be a make work project in waiting.

roger

[Grump]

Although I could do whatever I want on this new deck, I've already put decks around 4 sides of the house already. They are all redwood.

http://grumpsplace.com/images/home/addition0179.jpg

So, what do I do to prevent or inhibit rot? And while I'm at it; is there a product that will help bring back the natural color of redwood that has grayed a bit -- so I can then apply a finish to protect it?

Grump

[Rich]

It looks like your main area of concern is at the connection of the deck ledger to the house.. correct? Take a 4" drip edge flashing and put against the house and on top of the ledger board. Your first deck board should then be approximately 1/2" away from the edge of the siding (not the wall). The tops and sides of the joists should then have some type of epoxy paint or more drip edge flashing to protect the water that will drip off the 4" drip edge.
The following URL shows a half decent section (althought it doeesn't account for how to handle the water that gets onto tops of joists) http://www.boardwalkbuilders.com/pages/art/art8b.htm

[Grump]

Thanks, Rich, that's some helpful information. However, I am still wondering what I should do about the existing damage. Is there something I put on it to stop it in its tracks, or do I need to remove the damaged boards and replace them?

And about those sistered joists I want to add for the bathroom extension...

Thanks,

Grump

[Rich]

As far as wood fillers - here are a few on this page that can be sawn, screwed, etc
http://paint-and-supplies.aubuchonhardware.com/patching_and_drywall_compounds/wood_filler_and_putty.asp