Protecting slab insulation?

[VietGnome]

Concrete guys are in putting up the last of the insulation around the slab.

The plans call for it to end below grade, however with the 2' sheets they come right above grade, and up the 8" knee wall a few inches below the framing.

I'm not upset about it because more insulation, but now I need to figure out how to finish it.

The knee wall bows out in a few places anyways, so I was planning to flash the entire bottom perimeter, put J-trim ontop, and side up from there.

As far as protecting the foam, what options do you all recommend? I've read about parging it, and cement board. Curious on opinions either way. Id prefer to keep it cheap as possible, but I'm also supportive of spending a little extra to "overdo it"

Edit: photos

 

[jack stand]

This is probably a little extreme compared to your plans, but I'd find a used or 2nds rigid foam supplier and put matching (2")? foam on all of the walls especially if you plan on insulating anyway.
Locally I can buy 2" foil faced 4x8 foam for under $25/sheet from the Amish. Exterior foam is really the best system that they use these days.
It would require mailers on the foam or set on the sheathing and foam sheets in-between.
You'd end up with a exterior flat and continuous right to the grade that I'd finish with a PT 2x8 at the grade, covering the foam from the sun and damage and flash the top to run your siding onto.

 

[VietGnome]

This is probably a little extreme compared to your plans, but I'd find a used or 2nds rigid foam supplier and put matching (2")? foam on all of the walls especially if you plan on insulating anyway.
Locally I can buy 2" foil faced 4x8 foam for under $25/sheet from the Amish. Exterior foam is really the best system that they use these days.
It would require mailers on the foam or set on the sheathing and foam sheets in-between.
You'd end up with a exterior flat and continuous right to the grade that I'd finish with a PT 2x8 at the grade, covering the foam from the sun and damage and flash the top to run your siding onto.

Ill look around but I think that might be out of my price range. 2" XPS here is savagely priced. I almost didnt do full under slab insulation.

Im debating getting Coil stock and having one continuing piece of flashing from house down the side to grade.

I worry about stucco or parge not staying on. And cement board is thick and unsure how I would adhere it.

 

[jack stand]

Coil will "oil can" terribly in the dimensions you need.
What's your siding (above) going to be?
Edit: I wonder if there's a foundation "tar" that's not aggressive with the foam?
Painting things like this down low dark kinda makes it go away, at least at a glance.
Then there's low foundation shrubbery!

 

[kj_mustang]

Galvanized steel mesh attached with long washered ramset type pins. Stucco it or mortar screed it and then apply stone veneer. Z flashing over the top edge then your siding.

 

[Fav Onefour]

I have the same insulation setup around a home foundation. I scuffed the foam and applied stucco. It was a dumb idea. I had areas that flaked off pretty quickly with light contact while finishing up landscaping. If you don't reapply the stucco right away, the foam breaks down and won't hold new stucco.

Go with the steel mesh method @kj_mustang , is suggesting. Use good Z flashing and gap your siding correctly.

 

[VietGnome]

I'm really thinking about buying 1/4" cement board ripping it in 12" tall stripes, covering the foam with it, then use 1/4" tapcons and sink it into the foundation, then flash the top

 

[VietGnome]

I have the same insulation setup around a home foundation. I scuffed the foam and applied stucco. It was a dumb idea. I had areas that flaked off pretty quickly with light contact while finishing up landscaping. If you don't reapply the stucco right away, the foam breaks down and won't hold new stucco.

Go with the steel mesh method @kj_mustang , is suggesting. Use good Z flashing and gap your siding correctly.

Galvanized steel mesh attached with long washered ramset type pins. Stucco it or mortar screed it and then apply stone veneer. Z flashing over the top edge then your siding.

I like the Stone veneer idea, but it sounds a little expensive and will end up sticking out much further than the framed wall.

I think in the interim I'm leaning towards tapcon cement board to the foundation, and flashing it. I feel that will be faster was well compared to trying to stucco it for the first time.

 

[mike93lx]

I'm really thinking about buying 1/4" cement board ripping it in 12" tall stripes, covering the foam with it, then use 1/4" tapcons and sink it into the foundation, then flash the top

Feels like a lot of work and likely cracked and wavy cement board

 

[VietGnome]

Feels like a lot of work and likely cracked and wavy cement board

Why do you think it would be wavy? I wouldn't torque the piss out of it risking stripping out the screws.

I feel like it's less work than stucco by a landslide and easily replaceable.

1/2" is also an option

 

[mike93lx]

Why do you think it would be wavy? I wouldn't torque the piss out of it risking stripping out the screws.

I feel like it's less work than stucco by a landslide and easily replaceable.

1/2" is also an option

1/4 cement board isn't very strong, so without a really flat surface (you mentioned a bow) , you won't be able to ensure it's flat. Also, how will you deal with the screw heads?

 

[jack stand]

I'd agree with Mike about 1/4" being rather flimsy.
Then none of the "concrete" board is really approved for the direct weather. Painting the Hardy tile backer works well but how you'd handle the joints, I'm not sure.
I do believe that there is a type of construction glue that won't melt the foam and could be great limiting the amount of fastening that you would need otherwise.
I'd sure try to set the tap tapcons the last little bit by hand and not pulling the head in past the surface.

 

[VietGnome]

1/4 cement board isn't very strong, so without a really flat surface (you mentioned a bow) , you won't be able to ensure it's flat. Also, how will you deal with the screw heads?

Screw heads would likely stay exposed.

The surface is quite flat. Most of the bow in concrete is below grade. A bow above grade is a matter of 1.5" over 40'

Would 1/2" be better? Im trying to keep the profile low as well as strong and protective. While also being somewhat affordable and not take a ton of time.

I feel like stuccoing a 10-12" strip the entire circumference would be a massive PITA, and also not that strong.

 

[VietGnome]

I'd agree with Mike about 1/4" being rather flimsy.
Then none of the "concrete" board is really approved for the direct weather. Painting the Hardy tile backer works well but how you'd handle the joints, I'm not sure.
I do believe that there is a type of construction glue that won't melt the foam and could be great limiting the amount of fastening that you would need otherwise.
I'd sure try to set the tap tapcons the last little bit by hand and not pulling the head in past the surface.

Perhaps 1/2" is better?

This is just the solution recommended by my carpenter. And it seems the easiest/strongest at face value?

I'd consider stucco but doesn't exactly seem super strong, and a pita to do, as well as still needing to tap into the concrete for the mesh

Edit: looking into the stucco method to be well informed. seems there's several layers, looking to see if it's all available.

 

[pcmeiners]

You need to consider termites, that foam is awfully close to the wood sill. Would advise, in the least, is to buy Termidor, use it, good for approx 10 years.

 

[VietGnome]

You need to consider termites, that foam is awfully close to the wood sill. Would advise, in the least, is to buy Termidor, use it, good for approx 10 years.

I've never really heard of termites in my neck of the woods. It can get trimmed down a little if needed.

 

[mike93lx]

You need to consider termites, that foam is awfully close to the wood sill. Would advise, in the least, is to buy Termidor, use it, good for approx 10 years.

I think Boracare is the better choice. It's for pretreatment and preventative. Termidor is a termiticide.

 

[Overboost44]

Unless I am missing something, why not just take about a foot off of the insulation and then run fill up to the top? Is there a reason to have that much insulation above grade? Then you can just stucco the block.

 

[mike93lx]

Unless I am missing something, why not just take about a foot off of the insulation and then run fill up to the top? Is there a reason to have that much insulation above grade? Then you can just stucco the block.

The purpose is to insulate... Ideally, he'd wrap the whole exterior

 

[VietGnome]

Unless I am missing something, why not just take about a foot off of the insulation and then run fill up to the top? Is there a reason to have that much insulation above grade? Then you can just stucco the block.

Like Mike said, insulate. Otherwise I'm leaving an 8x8 cold heat sump along the stem wall. If I can spend a few hundred and keep R10 all the way up to the walls id be happy.

 

[AC-WC]

Pretty sure you don't have a Menards in your neighborhood but someone should have something similar to this?

Pardon Our Interruption

They have thicker stuff as well.

 

[1233user]

I bent up stainless steel sheet metal to protect the exterior foundation foam on my garage build. I built this in 2013, it is holding up great and from 10+ feet away you don't even notice that it's not the foundation you are looking at.

 

[mike93lx]

I bent up stainless steel sheet metal to protect the exterior foundation foam on my garage build. I built this in 2013, it is holding up great and from 10+ feet away you don't even notice that it's not the foundation you are looking at.

That's creative!

 

[Fav Onefour]

I'm surprised how many of these suggestions I've used.

I used grit faced foam boards that @AC-WC , mentioned. They were installed on the inside of my garage when I redid the floor and added heat. The exterior foundation was hard to access with a pad along one side and a patio on the other side. I figured the foam boards inside were better than nothing. I've found that the grit holds fairly well but it collects debris. I ended up doing a light skim coat to make the surface smoother. The biggest downfall of that style is the foam underneath. I've whacked a few spots and smashed the foam. That creates a spot that needs recoating. The upper edge is still exposed foam and would need protection from sun. The panels are easier to skim coat vs skuffed smooth panel foam and the coating holds pretty well.

I did a cheap version of the method @1233user , mentioned. I had a siding guy run aluminum through his forming machine. The sheets were twelve inches wide and formed with a Z style top edge. He added a middle ridge along the sheet for rigidity and to break up the smooth section. @VietGnome , You could check around to see if any of the seamless gutter-siding guys would do a chop and drop. It's usually not a big deal to select a color out of the standard stock. They might need to do multiple profiles to cover the entire foam height. I'm not sure how you would attach multiple sheets. I was able to attach mine at the top and used back fill to hold the lower section.

 

[VietGnome]

I'm surprised how many of these suggestions I've used.

I used grit faced foam boards that @AC-WC , mentioned. They were installed on the inside of my garage when I redid the floor and added heat. The exterior foundation was hard to access with a pad along one side and a patio on the other side. I figured the foam boards inside were better than nothing. I've found that the grit holds fairly well but it collects debris. I ended up doing a light skim coat to make the surface smoother. The biggest downfall of that style is the foam underneath. I've whacked a few spots and smashed the foam. That creates a spot that needs recoating. The upper edge is still exposed foam and would need protection from sun. The panels are easier to skim coat vs skuffed smooth panel foam and the coating holds pretty well.

I did a cheap version of the method @1233user , mentioned. I had a siding guy run aluminum through his forming machine. The sheets were twelve inches wide and formed with a Z style top edge. He added a middle ridge along the sheet for rigidity and to break up the smooth section. @VietGnome , You could check around to see if any of the seamless gutter-siding guys would do a chop and drop. It's usually not a big deal to select a color out of the standard stock. They might need to do multiple profiles to cover the entire foam height. I'm not sure how you would attach multiple sheets. I was able to attach mine at the top and used back fill to hold the lower section.

I have a buddy that can bend Coil stock if that's what you're asking. I've thought about that but I have no idea how id attach it and not have it oilcanned to all ****.

Are you suggesting a one piece Drip Edge to grade? You attached it at the top and just backfilled against the edge along the bottom?

 

[Fav Onefour]

I have a buddy that can bend Coil stock if that's what you're asking. I've thought about that but I have no idea how id attach it and not have it oilcanned to all ****.

Are you suggesting a one piece Drip Edge to grade? You attached it at the top and just backfilled against the edge along the bottom?

Sounds like you have the jist of what I meant.

How much height will be left exposed after you back fill? I only had about 8" of aluminum from grade to siding after back filling. The top part of the Z bend is about 1" and it's tucked under the siding. I didn't use fasteners directly on the strip. The bottom siding fasteners go through the top portion of the flashing.

I guess it would bother me to see ripple marks closer to line of sight. I didn't notice "oil canned" effect in my example. Admittedly, I wasn't really looking too close either. My goal was to have something better than siding that close to grade. The flashing is now glopped up with rain/dirt splatter, and grass chunks from mowing and weed whacking.

 

[VietGnome]

Sounds like you have the jist of what I meant.

How much height will be left exposed after you back fill? I only had about 8" of aluminum from grade to siding after back filling. The top part of the Z bend is about 1" and it's tucked under the siding. I didn't use fasteners directly on the strip. The bottom siding fasteners go through the top portion of the flashing.

I guess it would bother me to see ripple marks closer to line of sight. I didn't notice "oil canned" effect in my example. Admittedly, I wasn't really looking too close either. My goal was to have something better than siding that close to grade. The flashing is now glopped up with rain/dirt splatter, and grass chunks from mowing and weed whacking.

I see what you mean. Ill see if that's an option. How bad of a beating does it take? I wonder if the cement board would be more durable/replaceable in the long run

 

[Fav Onefour]

I see what you mean. Ill see if that's an option. How bad of a beating does it take? I wonder if the cement board would be more durable/replaceable in the long run

I'd say that about 90% of the damage is self induced at home. My foundations with buffer landscaping are pretty decent. I have a couple patios that **** up against the foam and I have to watch it when I shovel snow.

I have a lawn service doing the yardwork around the property where I installed the aluminum protective layer. The aluminum has marks from edger lines and mower decks rubbing but it seems to be holding up pretty well. Some of their guys could wreck siding all day long. Vinyl was no match to their abuse.

 

[danfromsyr]

I covered with 3/4PT plywood cut to 24inx96in over my foundation foam.
painted it a dark grey, used 2 different paints.. one is holding up better than the other... so choose paint wisely.

 

[pcmeiners]

I have a buddy that can bend Coil stock if that's what you're asking. I

If you can guarantee the aluminum will not get wet or have moisture behind it , it is OK, other wise run with stainless as 123user has excellently done.

 

[Seubs070]

I'm planning on using this on my cabin building that has about 6" of foam exposed. Haven't used it before but it seems to get good reviews.

Pardon Our Interruption

 

[Fav Onefour]

I'm planning on using this on my cabin building that has about 6" of foam exposed. Haven't used it before but it seems to get good reviews.

Pardon Our Interruption

I have not used this product but I like the description. It includes the use of mesh in the instructions too. Sounds like it's designed just for the situation in this thread.