Driveways & Walkways
Clean lines, a proper base, built for daily traffic.
Garage & Basement Floors · Joliet & Chicagoland
Garage and basement floors, built for what they face.
Garage slabs that shed water and stand up to road salt, and basement floors set over the right layers underneath. Poured and finished by one crew across Joliet and Chicagoland.
- Covers
- Garage floors · Basement floors
- Basement floors
- In new Illinois homes, gravel and plastic sheeting go underneath.
Source: Illinois Admin. Code
What's included
Under your car. Under your house.
Two slabs, poured smooth and level and built for what sits on them.
Garage floors
Garage slabs pitched to drain and built to carry vehicles.
Basement floors
Basement slabs poured level over the layers that belong underneath.
Compare
Two floors. Two different jobs.
They look alike. What they face, and what goes under them, is not.
| Garage floor | Basement floor | |
|---|---|---|
| What it faces | Road salt dripping off cars, freeze-thaw at the door, and vehicle weight. | Ground moisture and soil gas from below. |
| What goes underneath | A compacted base. The residential code doesn't require a vapor retarder under garage slabs. | In new Illinois homes: at least 4 in. of clean gravel, then 6-mil sheeting lapped at least 12 in. |
| The detail that matters | Slopes toward the door or a drain so water and melted snow run out. | Floor openings and joints sealed with polyurethane caulk in new homes. |
Garage floor
- What it faces
- Road salt dripping off cars, freeze-thaw at the door, and vehicle weight.
- What goes underneath
- A compacted base. The residential code doesn't require a vapor retarder under garage slabs.
- The detail that matters
- Slopes toward the door or a drain so water and melted snow run out.
Basement floor
- What it faces
- Ground moisture and soil gas from below.
- What goes underneath
- In new Illinois homes: at least 4 in. of clean gravel, then 6-mil sheeting lapped at least 12 in.
- The detail that matters
- Floor openings and joints sealed with polyurethane caulk in new homes.
Sources: Illinois Admin. Code · Fine Homebuilding · Building Code Trainer
Replacing a floor in an existing home? We'll look at what's under it at your free quote visit.
How we build it
From the base up.
Both floors start below the surface. Here's the order.
- 01
Prep the base
The subgrade is graded and compacted. Soft spots come out so the slab sits on an even bed.
Source: Concrete Network
- 02
Set what goes underneath
The layers under the slab go in before the pour. In new Illinois homes, code calls for at least 4 in. of clean gravel under basement slabs, topped with 6-mil sheeting lapped 12 in.
Source: Illinois Admin. Code
- 03
Forms, slope, joints
Garage floors are pitched toward the door or a drain, and control joints are planned before the pour.
Source: Fine Homebuilding (IRC R309.1)
- 04
Pour & finish
Poured, leveled, and finished smooth by the same crew that prepped it.
- 05
Cure & protect
Cured before traffic. In cold weather, Joliet requires flatwork to be kept at 55°F for at least five days.
Source: City of Joliet
One crew from the base to the final finish.
The standard
The numbers under the floor.
From Illinois code, the City of Joliet, and NRMCA. Ask any contractor for theirs.
4 in.
Gravel under basements
New Illinois homes get at least 4 in. of clean gravel under the basement slab, a layer that lets soil gas be vented from under the whole floor.
Source: Illinois Admin. Code
6 mil
Sheeting on top
Over the gravel goes 6-mil sheeting, lapped at least 12 in., as a soil-gas retarder.
Source: Illinois Admin. Code
32°F
Cold-weather pours
Joliet allows flatwork at 32°F and rising, with the concrete protected at 55°F for at least 5 days.
Source: City of Joliet
4,000 psi
Where salt reaches
Where deicers reach concrete, like salt dripping off cars in a garage, NRMCA calls for at least 4,000 psi.
Source: NRMCA
Care
Keep it dry. Keep it clean.
Rinse off road salt
Salt that drips off cars in winter is still deicer. Rinse it off the garage floor, especially in the first year.
Source: NRMCA
Keep the path clear
Keep mats and storage off the route to the door or drain, so water keeps running out.
Seal the garage floor
A penetrating silane or siloxane sealer helps protect against salt and freeze-thaw.
Source: NRMCA
Keep basement seals tight
In new homes, openings and joints in the basement floor are sealed with polyurethane caulk. Reseal any that open up.
Source: Illinois Admin. Code
Yes. Under the residential code, the parking area slopes toward a drain or the main garage door so water and melted snow run out.
Source: Fine Homebuilding (IRC R309.1)
The residential code exempts garages and other unheated accessory structures from its vapor retarder rule. Basement and living-space slabs are a different story.
For new homes, Illinois requires:
- At least 4 in. of clean gravel.
- 6-mil sheeting on top, lapped at least 12 in.
- Sealed floor openings and joints.
- A 3 in. vent pipe set into the gravel.
Source: Illinois Admin. Code
Joliet's rule for flatwork: the air has to be at least 32°F and rising, and the concrete must be protected to stay at 55°F for at least five days.
Source: City of Joliet
Salt that drips off cars is deicer, and deicers drive scaling, especially on new concrete. NRMCA calls for at least 4,000 psi where deicers reach the slab, and no deicers in the first year.
Source: NRMCA
Yes. New garages need an approved concrete foundation and a permit with an accurate plat of survey.
Source: City of Joliet
Under the residential code, living-space slabs sit on a 6-mil vapor retarder that limits moisture coming up through the floor. Water coming in through walls or cracks is a waterproofing and drainage question, which is a separate specialty.
Get started
Let's get your floor right.
Request a free quote and we'll look at the space, what's underneath, and how water needs to move, then walk you through options and timeline. Prefer to talk? Call 815-836-1828, 7 days a week.
Free quotes, 7 days a week.