A botched concrete pour by a contractor to extend a patio by 150 sq.ft.
has resulted in an uneven surface. The outer region is the correct level
but the surface level smoothly slopes down to a level about one inch lower
near the center.

The contractor has suggested using a self leveling concrete pour to even
everything out. This would fill in with depths ranging from about an
inch near the center to essentially zero depth near the outer areas where
the new concrete pour meets the original patio.

How well will the self leveling concrete adhere to the surface near the
outer parts of the region where the fill depth would be essentially zero?

Should the outer regions be ground down to a minimum depth first?

Unfortunately ripping out the original pour is undesirable beacuase it was
reinforced with rebar.

Thanks for any insight and advice.

wrote:
A botched concrete pour by a contractor to extend a patio by 150 sq.ft.
has resulted in an uneven surface. The outer region is the correct level
but the surface level smoothly slopes down to a level about one inch lower
near the center.

The contractor has suggested using a self leveling concrete pour to even
everything out. This would fill in with depths ranging from about an
inch near the center to essentially zero depth near the outer areas where
the new concrete pour meets the original patio.

How well will the self leveling concrete adhere to the surface near the
outer parts of the region where the fill depth would be essentially zero?

Should the outer regions be ground down to a minimum depth first?
....

Depends on the product -- some manufacturers say theirs can be feathered
out, others require minimum thickness of from 1- to 2/16". In general,
the 2-part epoxy formulations are more likely (but not universal) to
allow feathering out while the polymer-modified cementitous products
require a minimum thickness. In short, follow manufacturer's
instructions carefully and read the product specifications first.

I would recommend one of the epoxy formulations for the purpose outlined.

--

In article , dpb wrote:
wrote:

snip

How well will the self leveling concrete adhere to the surface near the
outer parts of the region where the fill depth would be essentially zero?


snip

the 2-part epoxy formulations are more likely (but not universal) to
allow feathering out while the polymer-modified cementitous products
require a minimum thickness.
I would recommend one of the epoxy formulations for the purpose outlined.


Thanks for the advice. One more question...

Is self leveling concrete useless in matching levels with existing patio slabs
that have the slight sloping grade away from the hosue to properly channel rain
water away?