What slope should the ground have around a foundation?

A common target is the ground falling away from the foundation over the first several feet, roughly six inches of drop across the first ten feet. The exact figure depends on the lot and local requirements, but the principle is constant: water must move away from the structure, never toward it.

Can bad grading actually crack a foundation?

Yes. Water pooling against a foundation soaks the soil beneath it, and expansive or poorly compacted soil that swells and shrinks puts uneven pressure on the slab or footing. Over repeated wet-dry cycles that movement can show up as cracks, sticking doors, and uneven floors.

Does Gilbert's flat terrain make grading harder?

Flat ground does not drain on its own, so grading has to build the slope deliberately and carry water all the way to a street, swale, or drainage point. On a lot with natural fall the water has somewhere to go; on a flat Gilbert lot the entire drainage path has to be engineered into the finished grade.

How Site Grading Protects a Foundation in Gilbert

A foundation fails from the soil around it far more often than from the concrete itself. In Gilbert, where lots are flat and monsoon storms arrive in short violent bursts, the grade of the ground around a home is one of the most important defenses a foundation has. Good grading is quiet and invisible; bad grading shows up years later as cracks and stuck doors.

What site grading actually does

Site grading shapes the surface of a lot so water flows where you want it to. Around a home, that means the ground slopes away from the foundation in every direction, carrying rain and runoff toward the street, a swale, or a drainage point instead of letting it collect against the footing.

The goal is to keep the soil directly under and beside the foundation as stable and as dry as possible. Dry, evenly-loaded soil holds a structure steady. Soil that repeatedly soaks and dries out moves, and movement is what damages foundations.

The rule of moving water away

The basic standard is that the ground should fall away from the foundation across the first several feet, often described as about six inches of drop over the first ten feet. That initial slope is what stops water from ponding against the wall and finding its way down alongside the footing.

Why Gilbert’s conditions raise the stakes

Three local factors make grading especially important here.

Flat terrain. Gilbert and neighboring Chandler sit on very flat ground. There is little natural fall to carry water off, so drainage has to be built into the grade on purpose. A lot that looks level to the eye may actually slope back toward the house, funneling water exactly where you do not want it.

Caliche and hardpan. Under the topsoil, caliche layers do not absorb water well. Rain that soaks in hits that hardpan and spreads sideways, which can carry moisture toward a foundation if the surface grade is pushing water the wrong way. Working with the soil layers, not against them, is part of a good grading plan.

Monsoon downpours. The summer storm season delivers a large volume of water in a very short time. A grade that handles a light rain can be overwhelmed by a monsoon cell if it was never designed for that volume. Grading in Gilbert has to plan for the heavy storm, not the average one.

How the work is done

Proper grading is more than pushing dirt around. It starts with reading the lot, measuring the existing elevations, and figuring out where water currently goes. From there the surface is cut and filled to create continuous fall away from the structure, and the fill is compacted so it does not settle and reverse the slope later.

On many Gilbert projects, grading works hand in hand with drainage excavation, where swales or drainage lines carry water the last stretch to a legal discharge point. When both are planned together, the surface slope and the drainage path reinforce each other.

Compaction matters

Loose fill settles. If soil placed to build up a grade is not compacted properly, it sinks over the first few wet seasons and the careful slope you paid for turns into a low spot against the house. Compaction in the right lifts is what makes a grade last.

Signs your grade may be working against you

After a storm, walk the perimeter of the home. Standing water within a few feet of the foundation, soil that has eroded away from the wall, mulch or gravel washed into piles, or a damp line on the stucco all suggest water is not being carried away. Inside, new cracks in drywall corners, doors that suddenly stick, or floors that feel uneven can point to soil movement under the foundation.

Deciding what to do

If you see any of those signs, the fix usually starts at the surface, correcting the grade before spending on structural repairs. Regrading is far less expensive than foundation work, and in many cases it addresses the cause rather than the symptom. New construction is the ideal time to get grading right, but existing homes can be regraded too.

If you are planning a build or dealing with water pooling near a home, our site grading and foundation excavation pages explain how these are handled on Gilbert-area lots. Getting the grade right is the cheapest insurance a foundation can have.