# Siding leaves decking/subflooring exposed. How to cover?



## TMackey (Oct 31, 2017)

Hi,

I bought a property with an old cabin on it and the structure is a real hack job. 

The specific problem (among many others!) that I'm dealing with right now is that the framing was built directly on a patio deck and they didn't run the siding low enough so when it rains the water runs down the siding and on the side of the decking/subfloor which in turn lets moisture inside and under the stick framing and rots and causes mold to form inside the walls at the bottom. 

So my question is, how should I extend the siding just a few inches down so that the rain water would run past the decking into the ground? I thought about using flashing tape as a semi-temporary solution. Any thoughts? See the photo of the siding/decking below.

Thanks!


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## Snoonyb (Oct 31, 2017)

Pull the bottom nails, insert sheetmetal, reinsert nails.


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## bud16415 (Oct 31, 2017)

:agree:..............


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## nealtw (Oct 31, 2017)

TMackey said:


> Hi,
> 
> I bought a property with an old cabin on it and the structure is a real hack job.
> 
> ...


Is the shed finished inside or can you see the other side of this sheeting?

If not you will have to remove nails and that is not the easiest place to learn how to use the tools for that. 

You can try using this stuff to remove nails and if that does not work with out making a mess out of the plywood you might just use a power saw and cut the bottom of the sheet and remove a few inches. Install a Z flashing and another piece of wood. If needed we can help you with that.
[ame]https://www.youtube.com/watch?v=_ITcWXXIFjY[/ame]


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## joecaption (Oct 31, 2017)

I'd use a flat bar and tap it up under the siding where the nail is to get it out just enough to be able to slide in my sawz-all blade and cut the nail off instead of trying to remove it.
Then slide in a piece of Z molding under the siding keeping it about 1/4 " away from the siding.
Install new ring-shank or spiral galv. nails
Followed with a piece of 1X6 vinyl lumber to act as a trim board slid in under the Z molding.
No painting, never going to rot.


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## TMackey (Nov 1, 2017)

Thank you all for your replies.

I think I will go with the z-molding. The previous owner had made some siding repairs and left a bunch of off cuts that I can use as the strips under the z-molding. It'll be good to match the strips with the siding.


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## Sparky617 (Nov 1, 2017)

I like joe's idea better than putting wooden T1-11 that close to the ground.


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## joecaption (Nov 1, 2017)

T-111 should never be closer than 6" of grade.
If you insist on T-111 make sure it's primed and painted two coats on all sides before installing.
NO primer and paint in one!


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## nealtw (Nov 1, 2017)

TMackey said:


> Thank you all for your replies.
> 
> I think I will go with the z-molding. The previous owner had made some siding repairs and left a bunch of off cuts that I can use as the strips under the z-molding. It'll be good to match the strips with the siding.



Might have lost something in the explanation, but adding wood and flashing on the outside will not be a great idea. The flashing wants to start behind the siding.


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## Snoonyb (Nov 1, 2017)

nealtw said:


> Might have lost something in the explanation, but adding wood and flashing on the outside will not be a great idea. The flashing wants to start behind the siding.



Read post #5.


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## nealtw (Nov 1, 2017)

Snoonyb said:


> Read post #5.



I'am not sure that is what the OP meant. Just checking because we know what that siding will do with sitting water.


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## Snoonyb (Nov 1, 2017)

So, post #6 is ambiguous?


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## nealtw (Nov 1, 2017)

Snoonyb said:


> So, post #6 is ambiguous?



Maybe, I read it again and I am still not sure what the plan is.


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## Sparky617 (Nov 2, 2017)

Post 6 looks like the OP plans to put T1-11 cut-offs below Z-strip flashing to cover the exposed wood.  Joe's post (#5) recommended putting Z-strip flashing with PVC lumber (Azek or the like) below.  I'd agree with Joe's solution, or just putting regular flashing below with no wood, I wouldn't go for the OPs solution of using more T1-11 below the Z-flashing as that is just inviting rot and/or insect damage.


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## joecaption (Nov 2, 2017)

And metal flashing (except copper or stainless steel) in contact with pressure treated wood will corrode.


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## Sparky617 (Nov 2, 2017)

joecaption said:


> And metal flashing (except copper or stainless steel) in contact with pressure treated wood will corrode.



Unless they have changed the rules here we have to use galvanized flashing with the new PT wood.  I haven't had to pull a permit lately to see if it has changed again.  Do they make stainless steel Z-flashing?  All I see at Lowes.com is aluminum and galvanized.  I know aluminum flashing and the copper in the new formula PT wood will cause a reaction that will corrode the aluminum flashing.


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## Snoonyb (Nov 2, 2017)

Sparky617 said:


> Post 6 looks like the OP plans to put T1-11 cut-offs below Z-strip flashing to cover the exposed wood.  Joe's post (#5) recommended putting Z-strip flashing with PVC lumber (Azek or the like) below.  I'd agree with Joe's solution, or just putting regular flashing below with no wood, I wouldn't go for the OPs solution of using more T1-11 below the Z-flashing as that is just inviting rot and/or insect damage.



Correct, however neal feels that #6 is ambiguous, as opposed to aesthetic.


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## TMackey (Nov 2, 2017)

Thanks Joecaption,

That makes total sense. So when you say to keep the z-bar 1/4" away from the siding I'm assuming you mean not to butt up the level part of the metal to the bottom of the siding? Is that necessary so that I can fit a 1" thick piece of vinyl board under the z-bar lip? Because it seems like a 1" thick piece would be a little tough to get under the flashing otherwise.


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## joecaption (Nov 3, 2017)

You need a 1X6 piece of PVC.
A 1X is 3/4" thick, 5/4 is a true 1" thick.
Not going to try and explain it, just the way it is.
You do not want the Z molding tight to the old siding because water will get trapped there, and wick up the end grain of the T-111.


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## mabloodhound (Nov 4, 2017)

They make vinyl Z flashing.  Go to a local vinyl siding supplier. https://www.amazon.com/dp/B000FCIO7Y/?tag=skimlinks_replacement-20

Dave Mason


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## zannej (Nov 4, 2017)

Would it be a bad idea for him to paint the exposed wood with exterior paint as well?

Also, thanks for the info on the PT corroding aluminum flashing. I did not know that. That affects a few projects I have on my list. 

Thank you for the link to the vinyl flashing!

Good luck with your repairs!


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## Snoonyb (Nov 5, 2017)

Here is another; https://www.homedepot.com/catalog/productImages/400/29/29fb5eb2-ccbe-4401-bc56-837b1b5eaa06_400.jpg


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## nealtw (Nov 5, 2017)

zannej said:


> Would it be a bad idea for him to paint the exposed wood with exterior paint as well?
> 
> Also, thanks for the info on the PT corroding aluminum flashing. I did not know that. That affects a few projects I have on my list.
> 
> ...



Galvanized steel or vinyl will work.


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## TMackey (Nov 6, 2017)

Thank you all for the replies. Much appreciated.


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## joecaption (Nov 8, 2017)

I have seen a piece of new pressure wood just sitting on a galvanized jet ski trailer eat right through the metal to the point there was none left at the top of a piece of channel iron.


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## nealtw (Nov 8, 2017)

joecaption said:


> I have seen a piece of new pressure wood just sitting on a galvanized jet ski trailer eat right through the metal to the point there was none left at the top of a piece of channel iron.



You are confusing aluminum with galvanized.

Aluminum is what gets eaten.
 [ame]https://www.youtube.com/watch?v=rkzQcQ_TGWA[/ame]


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## nealtw (Nov 8, 2017)

https://www.strongtie.com/products/...rrosion-information/pressure-treated-wood-faq

What metals and protective coatings does the Treated Wood Industry recommend for use with these products?
Hot-dip galvanized or stainless steel fasteners, anchors and hardware are recommended by the Preservative Treated Wood Industry for use with treated wood. This has been the position of this industry for years and their position has not changed with the transition to the alternative copper-based products. In the past this industry did not address the required levels of galvanizing, however most of those in the industry now provide information regarding the minimum level of galvanizing that should be used.

The thicker the galvanized coating the longer the expected service life of the fastener, connector, anchor, or other hardware will be.

Electroplated/electro galvanized and mechanically galvanized coatings should not be considered to be hot-dip galvanized. (Class 55, or higher, mechanical galvanizing provides galvanizing equivalent to the hot-dip galvanizing used on connectors and fasteners. Ref. ASTM B695 for additional information.)

It is also worth noting that the galvanized coating thickness varies depending on the galvanizing process used. Remember, the thicker the galvanized coating, the longer the expected service life of the steel will be.

Refer to the different chemical manufacturers and/or treaters as well for their recommendations. A list of trade names is included at the bottom of this page.


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