Protecting framing below grade

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slownsteady

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We're replacing a concrete landing with pavers. The concrete was about six inches higher than the foundation and butted up against the garage wall. As I'm chipping out a few inches of concrete to lay in the pavers, I have exposed the wood framing in the garage. The original sheathing was 1950's vintage fiberboard, and that is all gone. Pictures below will help explain. I want to make sure that I protect this area right, before I put in the pavers. The exposed wall is about 7' long. I'm guessing that I need flashing and plywood or a hardee backer type of product. So some questions on how to proceed.

How far down do I need to get the flashing?
Will construction adhesive be the right way to attach it?
Since there will be some concrete up against it and probably a one inch layer of sand, should I use hardee / cement board?
How far up do i need to go? I rather not pull off the old AL siding, because I know the older clapboard is still underneath, and I don't think the AL will take too much abuse without scratching or bending.
Any other things/concerns that I'm overlooking?

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Just my guess here. Looks like not that long ago someone put tin between the studs and then poured up to that. Why the short pieces I can’t figure out. I would put a long piece of tin up above the pour height at top and cover all the wood. Then pour up to it but higher than the finished slab height along the edge to make a curb out a few inches. Then a Z flashing that goes under the siding and across and down the curb about half way. Maybe some black joe under the first tin flashing.
I could be all wet.
 
Never heard of 'black joe' Is that like a roof patch product?

About the tin panels: That goes back about 25 years more or less. We had a carpenter ant problem in that corner of the garage. I hired a local guy who cut out the bad stuff and replaced with PT from inside the garage. We didn't touch the exterior at all. The panels were an attempt to keep critters out, but we knew that we couldn't really cover the framing by fitting them in between the studs. I haven't decided if I will go into the wall from the garage side yet, but it's likely if I need to make the proper repair here.
 
This done on new houses all the time, what ever the sheeting. You can get 6, 9, or 12 inch wide peel and stick with a primer that is sprayed on. it want to be low enough to stick to the foundation and come just under the aluminum and then slide galvinized sheet metal flat under the siding and have it extend below the blocks. Make sure the area has good drainage while you are there.
 
Sounds like peel and stick replaced black joe about 1962. What Neal said.

I would still think about a curb the height of the pavers with a “Z” bend counter flashing.
 
This should be a permanent fix this time. So, I like Neal's approach and would like another add-on ... If you can cut the slab back about 6", you can dig deeper to carry the peel and stick lower. This also allows for new drainage gravel. You can then re-pour to grade and install your pretty new pavers.
 
This done on new houses all the time, what ever the sheeting. You can get 6, 9, or 12 inch wide peel and stick with a primer that is sprayed on. it want to be low enough to stick to the foundation and come just under the aluminum and then slide galvinized sheet metal flat under the siding and have it extend below the blocks. Make sure the area has good drainage while you are there.

So, sounds like this peel&stick stuff goes right against the framing (?). Is it a roof flashing tape? Does it have a name? (I can't even look it up using peel & stick as keywords - too much garbage)
Then galvanized flashing over that gets shoved up under the siding. Is galvanized better than AL for this?

Sounds like i only need to get about 1" of foundation exposed for the flashing. That shouldn't be a problem. Then I can pour some cement to bring the grade up to the level of the remaining concrete which is the sub-base for the pavers.
 
This should be a permanent fix this time. So, I like Neal's approach and would like another add-on ... If you can cut the slab back about 6", you can dig deeper to carry the peel and stick lower. This also allows for new drainage gravel. You can then re-pour to grade and install your pretty new pavers.

I like the idea of drainage here but not sure how to incorporate gravel into the base. I'm taking down the existing slab about 4", to accommodate the pavers (2 3/8" and an inch or so of sand as a base. Doesn't leave much room for gravel. Of course i will have to go deeper near the wall to expose the foundation, so I can use gravel here I guess. Sort of a gutter to channel the water to the driveway. But I don't want to bring the water right against the wall, either framing or foundation, so i would need to create some kind of stand-off; maybe a curb like Bud mentioned.
 
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Never use aluminum against concrete or treated lumber.
We use peel and stick for windows like in this video. We find it in the lumber yards , it might have a name??
The peel and stick holds back the ground water and sheet metel is to make sure the water from the siding is outside the peel and stick. You can buy a roll of gavinized steel that is 6, 8, 10 wide or by the ft.
I would just repair the wall with plywood so that the wall is flush with the back of the aluminum so the tin sits flat when installed. It would be best to get the flashing behind the paper behind the siding because water comes down the inside too but, you do what you can .
[ame]https://www.youtube.com/watch?v=t2VOrk1MuWY[/ame]
 
I’m still not a fan of the sand base in this application. I think I mentioned this in the other thread. To keep the sand in place you will need to dam it off. Once you do that water will stay mixed in the sand under the pavers. It will allow movement of the pavers you will be forever pulling them up and resetting them. When you get a hard freeze they will also lift IMO. Ants will love nesting in the sand and you will even get weeds in the cracks.
If I was going to do lose pavers I would still rather set them on sleepers and allow water to get out of that area. It would require some kind of a fascia in the front though so you wouldn’t see the spaces.
If not that my next choice would be set them in mortar or pour a new cap and have it stamped and dyed to look like pavers.
 
The front step (ledge) will be replaced by wall stones from the same Mfr. Since they will be stacked, there will be enough gappage (new word!?) between the stones for water to weep out. I will use landscape fabric to keep the sand in. Polymeric sand between the pavers should lock out the weeds and (hopefully) the bugs. I understand your concerns about this, but I'm not about to reinvent the wheel; all the pros I've spoken to recommend the sand base.
 
Only time will tell, and you will be fine I’m sure. I haven’t done a lot with sand and fabric below. I did two good size paver patios at my mom’s house years ago and a brick patio at my old house and a couple brick paths. What I used to do every spring is take a wood block and a sledge hammer and any that were high I could hammer down and the sand was like a fluid and would raise the ones around it. I found that worked a lot better than pulling the low ones and adding sand. Roundup for anything that does get started in the cracks and sweep in some new sand each spring as needed.
Will you be using salt in the winter?
 
Did my backyard patio about 15 years ago. It's still holding up well. But as you mentioned, that's sand over soil and gravel. I have my concerns, but every material we looked at had concerns, except a new concrete pad, but we hope this will hold up as well and look better. BTW, a large rubber mallet works well in setting stray pavers.
I use salt sparingly...especially at the doorway. i expect i will use less now. I usually use sand for traction under foot, occasionally mixed with salt if i need it.
 
I clearing the edge away from the wall so I can get in there better, and it appears that there was already a bit of a curb up against the foundation, but the bond was weak and it is mostly not surviving the demolition. It came up about half to three-quarters alongside the sole plate. Which brings up the question; does that change the plan at all? Since it's mostly destroyed now, I doubt it would have made a difference.

The other question concerns the flashing tape. I was under the impression that it would go flush against the upper edge of the foundation and continue up the wall a good bit. So do I put the first course on before the plywood, or do I make a turn around the the bottom of the plywood and continue on the face of the plywood? Is the tape tough enough to make that seal and take the expansion / contraction between the materials?
 
When we see this being done it is usually at the covered front door area that does not get alot of water. And only the gavinized metal to protect the wood sheeting from coming in contact with the concrete. Thyis is usaully applied before the siding and then the siding is done. Bud called for flashing, which many call for but that only puts the water 1" away and really makes no difference. On the chance that surface water could work down and and become like ground water coming up behind the tin, I suggested the peel and stick to stick to a few inches of the concrete foundation and extend up higher than finished deck height all hidden by the tin.
In this video just imagine the peel and stick behind the metal.
[ame]https://www.youtube.com/watch?v=ejxTyh4d0hM[/ame]
 
In Neal’s vid the water will wick under the L flashing and right down that expansion piece IMO. That’s why I suggested a Z flashing over a curb the curb should be the height of the sand and pavers and can be poured at the same time the slab is pouredwith the tin all along the wood then the pour and then the Z counter flashing. If you want to put in a expansion piece that would be fine. I would just rip a 2x4 to the width of the sand and pavers and finish the curb flush with the top. The width of the curb could be figured out to come out right so you wont have to cut any pavers maybe. Imposable for water to get behind it.
 
Well, as luck would have it, the sole plate under the window hasn't done so well. No sign of bugs, but it looks like some dry rot. I guess I will be a bit further sidetracked on the pavers.

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