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bluedog225
04-11-2017, 10:41 AM
I believe it is called parge coating. I have a section of mortar type stuff below my bricks and cedar siding on my house that covers up the rough concrete foundation. It is up to an inch thick in places.Some has fallen off or been damaged during the course of foundation repair.

Any tips or tricks for redoing it? Initial research says mix masonry sand with Portland and trowel it on a wet surface.

I was thinking of taking it all off to the corner and painting on a bonding adhesive for good measure. Maybe I should drill some holes and fasten some masonry fasteners or wire?

Thanks

Tom

SMARTINSEN
04-11-2017, 12:46 PM
Maybe I should drill some holes and fasten some masonry fasteners or wire?

#7 rebar ought to do it.

bluedog225
04-11-2017, 01:03 PM
Ha!

jackster
04-11-2017, 02:28 PM
Clean all surfaces well and remove all loose areas. Apply the bonding agent...
https://www.whitecap.com/wcsstore/WhiteCap/Images/Catalog/WhiteCap/FullImage/f_438132390.jpg
Apply a surface-bonding cement ...
http://c.shld.net/rpx/i/s/pi/mp/22023/prod_6370705616?src=http%3A%2F%2Fmedia.toolboxsupp ly.com%2Fmedia%2Fcatalog%2Fproduct%2F1%2F0%2F10458 640_ka_29102015.jpg&d=147f7d48842fc56e24e51679b413cd617069bfad&hei=520&wid=520&op_sharpen=1
A portland cement based product with fiber reinforcing that also comes in white. Mixed with water and/or the bonding agent to troweling consistancy.
Good luck.

Figment
04-11-2017, 02:35 PM
If you do the wire mesh you're basically doing "stucco" instead of pargeing. nothing wrong with that, but you may be gold-plating the situation, and shooting fasteners into the concrete wall could just be a way of making the project a lot bigger.

As far as tips and tricks.... no. it's not rocket science, it just takes practice. Like painting, just before you reach the point where you're kinda-good at it, the job is finished.

Keith Wilson
04-11-2017, 02:40 PM
. . . just before you reach the point where you're kinda-good at it, the job is finished.Ain't that the truth. That covers just about any kind of job around the house. And by the time you have to do it again, you've forgotten everything you learned.

Stiletto
04-11-2017, 08:14 PM
I've done a few repairs on this type of surface in the past. I found that mixing acrylic paint 50:50 with the water for the plaster guaranteed adhesion where plaster alone was problematic.

Do a trial run first to get a feel for it.

Gib Etheridge
04-11-2017, 09:42 PM
I've done a bit of parging over dry stone basement walls in old colonial buildings back east, also a few block and a few brick chimneys. 1 shovel of mason's lime, 2 of Portland, 3 of mason's sand as I remember it.

Surface must be clean and wet. If it is soaking up the water right away wet it again, and more as necessary. Don't let the mortar dry too fast, the longer it takes the better, so shade it and apply when it's cool.

You can add that white glue looking stuff for greater adhesion. I've forgotten what it's called.

Phillip Allen
04-11-2017, 09:44 PM
your arms are gonna get tired :)

Old Dryfoot
04-11-2017, 10:08 PM
Acrylic modifiers like 900x or Acrylbond will help with sticking it all in place. But it still needs to be clean, clean, clean.

I'll be parging about 30 sq/ft of foundation early next week.

oznabrag
04-12-2017, 06:21 AM
Acrylic modifiers like 900x or Acrylbond will help with sticking it all in place. But it still needs to be clean, clean, clean.

I'll be parging about 30 sq/ft of foundation early next week.

It's my understanding that wet Portland will not bond to cured Portland without a modifier.

Old Dryfoot
04-12-2017, 08:42 AM
It's my understanding that wet Portland will not bond to cured Portland without a modifier.

Mine as well.

At work, we also tend to acid wash everything, just to ensure a good toothy surface.