I need to reattach some slates (or flagstones, I am not sure of the difference) on my mother’s front walk. It will be redone at some point so the repair does not have to be permanent, just “good enough”. The constuction was originally poured concrete with the slates laid on top, sort of into the wet concrete and then more concrete was used as a sort of grout between the slates. Some of the slates are loose and can be picked up off the concrete base. When the slates come up there is no concrete stuck to them and the rough back of the slate leaves a matching impression in the concrete base.
I don’t know if the concrete should have stuck to the slates or if the concrete grout between the slates just sort of held them in place.
What would be best to reattach the slates to the concrete? Bear in mind that the entire walk will be replaced so I don’t want to go overboard with working on the concrete base. I would prefer to sort of glue the slates down to the concrete and then maybe fill in around them with some new “grout”.
One of my concerns if I use some thinset type of material is that it will raise the level of the reattached slates above that of the ones that are still in place creating a trip hazard. I thought of maybe some polyurethane construction adhesive and then some topping mix or mortar to fill in the grout spaces. Will the construction adhesive stick to the slate and concrete? The tube says it is good for concrete and masonry but no mention of stone or slate. Any other ideas?
Thanks.
Replies
If you're replacing it...........and you can get them to fit down pretty good after cleaning out the voids.............go for it with the glue.
Fill in the joints with sand mix (no lime).
Use it!
I squirted some Great Stuff foam on a flagstone wall to "glue" a few bricks in place, so the toddler who plays in the yard will quit moving them (and possible dropping one on his toe). That was 3 years ago and they're still stuck to this day.
I'm sure the glue would work also.~ Ted W ~
Cheap Tools! - MyToolbox.netSee my work - TedsCarpentry.com
Thanks to all.
Much easier to squeeze it out of a tube (although I just used some PL premium and I think it was designed for Popeye sized forearms - tough to force out with a regular caulking gun) than it is to mix up a batch - even though I am 1/2 italian.
Aw come on. You're 1/2 Italian and you're asking a masonry question?Steve
I almost said that, but I was afraid my 1/2 itaian wife might be reading over my shoulder!>G<
It was the german half that needed to be precise about it, the italian half would have just winged it.