Can you pour concrete on concrete to fix an uneven surface for garden shed foundations?

Answer 1

Sorry.No, it will not stick, and if you use quick-rite, it will end up chipping sooner rather than later.

Long answer.

There are three challenges to resurfacing concrete.

Firstly Interslab adhesion: to get wet concrete to stick to dry concrete an adhesive is necessary.

Secondly minimum slab thickness: Concrete typically does not have the strength to stick to it's self if it gets too thin (3" typical). Special blends can overcome this by having smaller minimum thickness, but these blends tend to have smaller maximum thickness as well. for example one polymer modified concrete can go down as thin as 1/4" but has a maximum thickness of one inch.

Thirdly layered systems do not have uniform porisity and can be more vulnerable to water and salts than a monolithic slab, and should be sealed.

I Agree with what this person has said. But there are alternatives to fix your existing floor. Depending on how bad the existing floor is, you can power wash the existing concrete floor and place an epoxy floor on top of the bad concrete. If you want to know what an epoxy floor looks like, a lot of schools have epoxy floors. Ever pay attention and realize a schools floor looks like linoleum, but there are no seams. That's because it is an expoxy surface spread over a concrete floor.

There are many alternatives to patching and repairing your floor, but standard concrete on top of an existing concrete slab doesn't hold up well.

For this application I would recommend a "self-leveling compound" which is also called "self-leveling grout". It is a thin mixture designed to flow evenly and level out hills and bumps in concrete (or stable wooden sub-floors) prior to applying ceramic tiles. But it can also be used to cover/level cracks or dips such as a floor that originally was sloped for a drain. Once dry and cured you can put any covering you want on it.