Slab foundation building in O'Fallon MO - a solid base and a dry floor above it
Need a slab under a new home or garage? We build it from the dirt up, in order, so the floor starts solid and dry.
- Licensed and insured.
- Free quotes on site.
- Expect a reply within 1 business day.
Fix the old slab or pour a new one?
If the old slab is still level and dry, a repair usually holds. If it's sinking or damp all over, the trouble is underneath, and only a new slab fixes that.
A repair is enough when:
- Cracks are thin and not growing
- The floor is still level
- No damp comes through
- The edges are solid, not crumbling
- Flooring is staying put
A new slab makes sense when:
- Sections have sunk or tilted
- Cracks keep getting wider
- Damp ruins every floor covering
- The base underneath washed out
- You want radon features under it
How your slab gets built
You call or write
Call (636) 614-2331 or send the form with the lot address, your house plans and the slab size, so I know the job before I come out.
A site visit set
I look and measure
I come out myself to look at the ground and the drainage, measure, and walk you through your choices, like radon features that have to go in before the pour.
Your options explained
Written estimate and plan
You get the estimate in writing, with what's included and what isn't, plus a plan that lays out each step in order, including when you can walk on the slab.
A written estimate
Permits and inspections
We check with the offices that cover your address and handle any paperwork. Inspections booked on the city's portal are typically done the next day, so we plan the pour around them.
Permits lined up
Pour, finish and walk-through
Our crew forms, pours and finishes the slab, then cleans up. I walk it with you and go over curing, the days it needs to gain strength before heavy use.
A finished slab
What our slab foundation work includes
Layout and digging
We mark the footprint from your plans and dig out the soil down to firm ground.
Packed ground underneath
We compact the subgrade in layers, so the slab rests on ground that won't settle with time.
Gravel layer
Clean, coarse gravel goes down next, so soil gas has room to move under the house instead of into it.
Plastic sheeting
Heavy plastic goes over the gravel to keep soil gas and damp out, and to stop wet concrete from clogging the gravel.
Forms and rebar
We set the forms and the rebar, steel bars that hold the slab together if it cracks.
Pour, finish and cure
Our crew pours, levels and smooths the slab, cuts the joints and keeps it damp while it cures.
What sets the price of a slab foundation?
Size and thickness come first, since they set how much concrete, gravel and steel the job takes. After that it's the site. How much dirt has to come out, how close the truck can get, and whether the ground needs fill or extra packing all show up in the price before any concrete does.
Your choices add to it too. Radon features, thicker edges under bearing walls and extra steel cost more, and they cost less decided now than added later. The schedule mostly turns on the permit, the inspections and the weather, and plans that are ready move things along. Your written estimate puts a figure on your own job.
Why O'Fallon owners call us for slab work
I started D&R in O'Fallon in 2017, after years of building schedules for a busy company, so every slab gets laid out in order before anything is poured. Most problems I see start earlier, with the base, the drainage or a rushed schedule, and that's where we spend our time. Builders also call us for foundation installation and concrete parking lots.
- Your estimate done by me, on site
- A written plan in the order it happens
- Questions answered before you sign
Get a written estimate for your slab foundation
Send the lot address, your house plans and the slab size. We'll reply within one business day to set up a free on-site estimate, with no obligation.
(636) 614-2331Slab foundation questions we hear
How much does a slab foundation cost near O'Fallon, MO?
A concrete slab foundation in the St. Louis area usually costs about $4.50 to $18 per square foot. That's a wide range, because the site, the thickness and the layers underneath change a lot from one job to the next, so treat it as a broad guide. Your free written estimate gives the figure for your lot and plans.
Do I need a permit for a slab foundation in O'Fallon?
Check with the city's Building Division, which issues permits for new homes, garages and major alterations, though its list doesn't name slab foundations by themselves. It also reviews plans for new homes, so have yours ready. Grading permits come from the city's Engineering Department, and if an independent fire district covers your address, it may want its own permit. We're licensed and insured, and when a permit is needed we handle the paperwork and line up the inspections.
Should I add radon protection to a new slab foundation?
The EPA says building radon-resistant features in during construction typically costs less than reducing radon in the house afterward. The vent pipe from the gravel layer gets stubbed up when the slab is poured, so the choice has to be made before the pour. That's why I bring it up at the estimate.
Why does the amount of water in a concrete mix matter?
Less water for the same amount of cement makes stronger concrete, and the more water in the mix, the more the slab shrinks as it dries. Extra water makes concrete easier to pour, which is why some crews add it. We keep it out, and you can ask any crew how they control it.
How do I keep moisture from coming up through a new slab floor?
Keep the plastic sheet under the slab whole, because one maker's guide warns that even small holes in it can significantly raise the moisture coming through the floor. Those holes often come from foot traffic during construction and can lead to flooring failures later. We keep traffic off the sheet while we set up and pour.
What causes cracks in a new slab foundation?
Most cracks come from a base that settles, too much water in the mix or joints cut late, and in St. Charles County the soil plays a part too. One independent analysis estimates about 41% of the county's soil area is expansive clay, which swells when wet and shrinks as it dries. We dig to firm ground, pack the base and cut joints on time, so cracks are more likely to follow the joints.
Slab work in and around O'Fallon
We're based in O'Fallon and pour slabs in St. Peters, Wentzville and the cities around them. Pick yours below, or call (636) 614-2331 if you don't see it.
Slab quotes from D&R O'Fallon Concrete Company
Call (636) 614-2331 for a free on-site quote, and get the work before the pour planned in order.