"maurice" wrote in message
oups.com...
My front sidewalk is about 40 years old, and is pretty much one big
slab from the front porch to the driveway. It's fallen as much as
three inches in one corner, which means that rain and melting snow
puddle all the time. Also, the surface of the concrete is pretty bad,
probably from all of the ice-melting agents the previous owners likely
used to deal with the ice build up from the puddling. However, the
slab has no cracks in it.

On one side of the slab is a big brick planter, which I'd like to keep.
With today's price of concrete, I'm wondering if it's worth it to jack
the slab up and refinish the top? Also, I heard of a process that uses
Urethane foam instead of mud to jack the slab, apparently it results in
smaller holes and less settling. Any experience here on this issue?
And any suggestions on the topping to use?

I'm in a cold climate (Northern Alberta, Canada) so frost heave is
always a problem (though this problem is probably more related to
settling.

Thanks for any and all suggestions.

Concrete gets its hardest at 100 years old and all concrete cracks.

Slab jacking can get expensive if you're wanting to keep what you got
instead of a tearout and replacement.

You didn't mention the square feet of your sidewalk aka "one big slab", nor
how far off grade the slab is where it has fallen, both variables effecting
a good answer for you.