Some problems with new concrete are normal and harmless, and some point to poor work. A thin crack along a joint is usually fine. A slab that flakes in its first winter, holds water or was poured without the steel in the quote is not. This page explains which is which and what to do.
Why is my new concrete already cracking?
New concrete shrinks as it dries, and if it is not given a place to crack, it cracks on its own. Control joints are cut so those cracks land in a straight line. Cracks that appear between joints usually mean the joints were too far apart or cut too late, the base was soft or uneven, or the slab dried too fast on a hot or windy day. A hairline crack is common. A wide one or one with a raised edge is not.
Is the contractor responsible for a crack that shows up weeks later?
It depends on the cause and on your contract. No contractor can promise concrete will never crack, and many contracts say so. But a crack caused by a thin slab, a missing base or joints that were never cut is a workmanship problem. Read the written warranty, photograph the crack with a coin for scale, and contact the contractor in writing. A good contractor will come look.
Why does my new concrete have dark and light patches?
Uneven color in new concrete is common, and it usually fades over the first few months. It comes from different drying rates, water added to one truck and not another, a curing blanket or plastic touching one spot, or the slab sitting over damp ground in one area. If the color is still blotchy after a season, a stain or a tinted sealer can even it out. Color alone does not mean the slab is weak.
What happens if it rains on fresh concrete?
Rain on fresh concrete before it is finished can wash out the cement at the surface, leave pits and make the top weak and dusty. Once the slab has been finished and has set for a few hours, a normal rain usually does little harm. Crews watch the forecast and cover the slab with plastic if a storm comes in. If the surface is pitted or powdery after rain, it may need a resurfacing layer later.
There are footprints, rough spots or a wavy finish with low spots. What can I do?
Footprints and rough spots are surface flaws, and low spots that hold water are a finishing or forming problem. Ask the contractor to come look. Small marks can sometimes be ground or patched. Puddles that sit for hours after rain are worse in Michigan, because that water freezes and flakes the surface. A wavy slab with real low spots may need grinding, an overlay or replacement of the bad section.
Are control joints really necessary? The crew says they will saw-cut them a week later.
Yes, control joints are necessary. They give the slab a planned place to crack as it shrinks. Waiting a week to saw-cut is too late, because the slab has usually cracked on its own by then. Joints are cut as soon as the concrete is hard enough not to ravel at the blade, often the same day or the next. A common rule is to space them no farther apart, in feet, than two to three times the slab thickness in inches.
My concrete was poured without rebar or mesh and I only found out after. What now?
First check the contract. If it listed rebar or mesh and the slab went in without reinforcement, the contractor did not deliver what you paid for, and you can ask for a credit or a fix in writing. Not every slab needs steel, and a well-built slab on a good base can perform without it. But on Downriver clay, steel helps hold cracked pieces together and level. Photos from the pour or a small core can show what is in it.
What can I do if the contractor will not come back to fix it?
Put your complaint in writing, with photos, the contract and a clear request and deadline. Send it by email and certified mail. If they will not answer, a contractor holding a Michigan residential builder or maintenance and alteration licence can be reported to LARA, and the Michigan Attorney General's Consumer Protection Division takes complaints about unlicensed contractors. For money disputes, small claims court is the usual route. This is general information, not legal advice.
Why is my new stamped concrete slippery, and why does older stamped concrete turn cloudy or peel?
Stamped concrete gets slippery because the sealer is glossy and smooth, especially when wet or icy. A slip-resistant grit can be mixed into the next coat of sealer. Cloudy or white sealer usually means moisture got trapped under it, often because it was applied to damp concrete or too thick. Peeling means the sealer lost its bond. In most cases the old sealer is stripped or treated and a thin new coat goes on in dry weather.
The surface is flaking after its first winter. Is that normal?
No. Flaking in the first winter points to a problem with the concrete itself or how it was handled. The usual causes are concrete without air entrainment, extra water at the surface during finishing, no curing, or rock salt used in its first winter. Photograph it and contact the contractor in writing. Shallow flaking can be resurfaced, but find the cause before agreeing to a fix.
It was poured in extreme heat and now it looks bad. Why?
Concrete poured in extreme heat, wind or full sun dries too fast at the top. That can leave a crust, shrinkage cracks, a weak surface and uneven color. Lincoln Park gets hot, humid summer days, and on those days a careful crew pours early in the morning, keeps the surface damp and cures it properly. If the top is cracked in a crazed pattern or dusts when you sweep it, ask the contractor what curing was done.
The stamped pattern is crooked, and I still owe the final balance. What should I do?
Do not pay the final balance until you have put the problem in writing and talked it through. Take clear photos of the crooked lines or uneven stamping, compare them with the sample or plan you agreed to, and ask the contractor to come see it. Some flaws can be fixed with grinding, staining or a recoat. A badly misaligned pattern may need part of the slab replaced. Keep the talk calm and in writing.
The crew left ruts in my lawn, washout and concrete splatter on the house. Who cleans that up?
The contractor should, if cleanup was in the contract, and it should be. Ruts from the truck, washout dumped in the yard and splatter on siding, brick or a neighbor's car are part of the job to clean up. Point it out in writing right away, with photos, because dried splatter is harder to remove each day. On narrow Lincoln Park lots, a careful crew protects the lawn and the neighbor's side before the truck rolls in.
My new pad is out of level and the forms are still stuck on it. Is that a problem?
A pad that is out of level by a small amount on purpose is normal, since outdoor slabs slope to drain. One that is out of level enough to tip a shed or hold water was not formed right. Forms are normally pulled a day or two after the pour. If they are still on weeks later, call the contractor. Stuck forms can be pried off, but take care not to chip the edge of the slab.
If you have a problem with concrete someone else poured, text photos to (313) 889-7953 and we will tell you honestly what we see.