sloping a concrete floor

Fixing a Poorly Sloped Concrete Floor for Drainage

Bad concrete can cause a number of problems. One common issue many home and business owners face is poorly sloped concrete.  This happens when the concrete contractor that places the original concrete slab either neglects , forgets or simply doesn’t understand the duty of the concrete being installed.  Concrete slabs not only provide a clean walking or functional useable surface, they are often used to guide or create drainage for water away from structures and buildings.

If you have ever experienced a rainfall followed by leaking near doorways, patio sliding doors, puddles in your garage or patio you may be experiencing the result of poorly placed and sloped concrete that causes water to flow in the wrong direction.

The good thing is that concrete can be repaired.  Not necessarily by removing it and redoing it but by adding a slope to its surface after the fact with specialized concrete repair products.

The general rule of thumb for a proper slope is that concrete should have a 1/4 inch drop for every foot of length.  So a typical 10 foot slab should have 2.5 inches height difference at one end to the other.

There are many products on the market that are designed to be applied to concrete and can be sloped, and are available in most local construction supply stores.

To demonstrate how to slope a concrete slab here is an example:

This particular project is an example of a sloped concrete slab being installed on a flat garage floor that did not drain.

First-  The floor is cleaned and prepped for the overlay.

Second – The Floor is primed to create proper adhesion

Third – A trowlable grade concrete topping mix is used to set the slope.

Fourth – Once cured the surface can be sealed or decorated.