Preparation
Subfloor Repair and Slab Leveling in Fort Worth
Grinding, patching, levelling pours and moisture testing — the work under every other service on this site, and the one most often left out of a cheap quote.
- Pricing
- Estimated after flatness and moisture are measured
- Timeline
- Set by cure times on any levelling pour, not by the labour to place it
This is the work nobody wants to pay for and everybody pays for eventually. It is also the honest way to compare three bids: ask each one to price preparation as its own line, and the cheap quote usually stops being cheap. What subfloor repair costs gives you the ranges to check those lines against.
Post-tension slabs come first
In Tarrant County, post-tension slabs became the norm from roughly the early 1980s onward. Steel tendons are tensioned through the slab after the pour and remain under enormous load for the life of the building. They do not run on a predictable grid.
Nothing gets cut, cored or fastened into one of these until the cables are located. That is a safety step before it is a flooring step, and it is why the first question we ask about a floor in Keller, Southlake, Colleyville, Mansfield or any subdivision built in the last forty years is what year the house went up. Choosing flooring for a post-tension slab covers what that constraint rules in and out.
The prairie and the clay
Fort Worth sits on a geological boundary, and it decides how much of this work a house actually needs.
West and north of the Trinity — Benbrook, Aledo, Saginaw, White Settlement — the Fort Worth Prairie is shallow soil over Goodland and Walnut limestone. Slabs there move very little. Preparation is frequently a morning of grinding.
East and south — Arlington, Mansfield, Crowley, Burleson — the Eagle Ford and Woodbine clays are strongly expansive. The same age of house on that ground can need a full levelling pour and an uncoupling membrane under tile. We explain when a pour is the right call in subfloor levelling and self-levelling concrete, and what sits between slab and finish floor in subfloor moisture barriers.
Neither is knowable from an address, which is why we measure rather than assume. And flatness is a present-tense measurement: a slab that was flat when the house went up in 1998 frequently is not now, and the builder’s original specification is not evidence about today.
What flatness tolerance actually applies
It is the flooring product’s tolerance, not a general standard, which is why we ask what you are installing before we measure:
- Most floating and resilient floors: about three sixteenths of an inch over ten feet
- Large-format tile: about an eighth of an inch over ten feet
- Wide-plank hardwood: tighter than narrow strip, because a long board bridges a dip
We survey the floor and record where and how far it is out, so the scope is a measurement rather than an impression.
Grind, patch, or pour
Grinding takes high spots down. It is fast, dust-contained, and by far the cheapest of the three.
Patching fills localised low spots with a skim or a trowel-applied compound.
A self-levelling pour is for when the deviation is too broad or too deep for either. Depth drives the cost — a quarter inch skim and a one and a half inch pour are genuinely different jobs — and the cure schedule drives the calendar.
A self-levelling underlayment corrects a surface. It is not a foundation repair, it lifts nothing, and it stabilises nothing. Where a slab is moving differentially rather than simply sitting unevenly, that is an engineer’s question and we will say so instead of pouring over it.
Moisture
In-situ relative humidity probes to ASTM F2170 are the reference test. They have to equilibrate before they read, which is why slab testing is booked ahead of install week. Calcium chloride testing to ASTM F1869 is used where a specification calls for it.
Where a reading exceeds what the adhesive or coating allows, an epoxy moisture-mitigation primer rated to a specific relative humidity ceiling is the correct answer. It carries its own manufacturer warranty tied to the tested reading, which is another reason the reading gets recorded and kept.
Wood subfloors
Re-decking, sistering joists, adding blocking, and plywood overlays where the existing structure will not carry the intended floor. Common in the pre-war pier-and-beam stock and in second storeys with a long span where deflection is the real problem rather than the decking.
Deflection is commonly held to L/360 for most floors and L/720 under stone or large-format tile — a tile floor over a springy span will crack no matter how well it is set.
Heat and sound control change the floor height
Electric or hydronic heat, and sound-control underlayments, are built into the substrate at this stage. Both change the finished floor height, which changes every threshold, door bottom and appliance opening in the room. They are designed here rather than discovered at a doorway.
Typical market ranges for this work
North Texas ranges gathered from published contractor pricing, so you have a reference point before anyone comes out. They are not our quote — where your job lands inside a range depends on what we find underneath.
Refinishing, repair and preparation
| Item | Typical range |
|---|---|
| Sand and refinish hardwood — 3 coats Species, how many previous sandings the boards have left in them | $3 to $6 per sq ft |
| Screen and recoat — no sanding Only worth it above bare wood; winter heating also opens gaps a recoat cannot fill | $1 to $3 per sq ft |
| Dustless sanding surcharge Containment matters more in an occupied historic home than an empty one | Usually folded into the sq ft rate |
| Board replacement — matched and woven in Matching a 1920s longleaf pine board is the expensive part, not the labour | $100 to $400 per board |
| Water damage repair — after a burst supply line How long the water sat, and whether the subfloor delaminated | $400 to $1,800 per room |
| Subfloor repair or replacement Joist condition in a pier-and-beam house is only knowable once it is open | $3 to $9 per sq ft |
| Slab grinding and flatness correction How far out of tolerance the slab reads against the material's spec | $1 to $4 per sq ft |
| Self-levelling underlayment pour Depth. A 1/4 inch skim and a 1.5 inch pour are not the same job | $2 to $8 per sq ft |
Typical North Texas market ranges, gathered from published contractor pricing. Not a quote.