Concrete
Replacing a concrete patio is one of those jobs where the quotes come back further apart than homeowners expect, and the instinct is to assume somebody is padding. Usually nobody is. Patio replacement is priced by a set of constraints that are genuinely different from the ones that govern a driveway or a house slab, and once you can see those constraints the spread between bids tends to explain itself.
This guide deliberately quotes no dollar figures. Concrete pricing moves with the metro, with material and fuel costs, with how the site is reached and with what is found once the old slab comes up. A national average number would be the least useful thing you could carry into a conversation with a contractor. What does travel between markets is the structure of the job, so that is what is set out here.
The single most useful thing to understand is that the two are engineered around different loads. A driveway has to carry vehicles, so its thickness, the compaction of the material underneath it and frequently its reinforcement are all dictated by that. A patio carries people, furniture and a grill. That is a real load, but it is not a vehicle load, and the specification that follows from it is lighter.
This cuts both ways when you are reading bids. A contractor quoting your patio at full driveway specification is not necessarily overcharging - they may simply be building heavier than the use requires, and it is a fair question to ask why. Equally, if you actually intend to park a trailer, a small boat or a vehicle on part of that surface, say so at the walkthrough, because that changes the build genuinely and it is far cheaper to specify it now than to discover it later.
Driveways sit at the street. A truck can reach them, a mixer can discharge close to the work, and a dumpster can sit alongside. Back-yard patios usually offer none of that, and every consequence of it lands in the labour column.
Demolition is where it shows up first. The old slab has to be broken up and carried out, and that is heavy material. Where a machine can reach the work, removal is fast. Where the only route is a side gate, a set of steps or a planted garden path, the same tonnage leaves by wheelbarrow, and the hours multiply. Then the process reverses for the pour: if a mixer cannot get close enough to discharge, the concrete has to be pumped or barrowed in, and it has to arrive fast enough to be placed and finished as one continuous slab.
This is the most common reason two honest bids on the same patio look nothing alike. They may be pricing two different routes in and out. If you want the spread explained, walk that route with each contractor and ask directly how they plan to get the rubble out and the concrete in.
Most patios sit against the building, and that adjacency introduces requirements a free-standing slab never has.
Slope is the first. The finished surface has to shed water away from the foundation, consistently, across the whole area. A patio that drains back toward the house is not a cosmetic flaw, it is a moisture problem aimed at the part of the building you least want it aimed at, and it is one of the more common reasons an older patio is worth replacing rather than resurfacing.
The joint where the slab meets the wall matters for the same reason. Concrete moves with temperature and moisture, the house sits on its own foundation, and the two need to be able to move independently without opening a channel for water at the wall. How that junction is detailed is a reasonable thing to ask about.
Finally, check where the finished height lands relative to any door threshold or siding. Pouring a new slab over an old one raises the surface, and a patio that ends up level with or above a threshold or the bottom of the siding creates a problem that is expensive to undo once it has cured.
Patios accumulate buried services over the years, and finding them mid-job is how a clean estimate turns into a change order. Irrigation lines, a gas run out to a grill or fire pit, low-voltage lighting cable, a downspout tie-in or an air-conditioning condensate line are all common under and around a patio.
Tree roots deserve separate mention. If a root has lifted or cracked the existing slab, it will do the same to a new one unless the situation is addressed, and the options there involve the tree as much as the concrete. A contractor who raises it during the walkthrough is estimating properly; one who does not may be pricing a job that is about to change.
Anything structural sitting on the patio - a cover, a pergola, a screen enclosure - is usually footed in the slab itself, and that dictates the sequence of the entire project. Mention it early.
Not every tired patio needs replacing, and it is worth being straight about that. The distinction that matters is not how bad the surface looks but whether the slab is still fully supported by the ground underneath it.
Cracking that is fine, with both sides sitting level and the slab solid underfoot, is a surface condition. Patching and resurfacing are honest answers to it, and they buy real time.
The signals that point the other way are differential. One side of a crack has settled below the other. A section rocks or sounds hollow when you step on it. Water now pools in the middle or runs toward the house where it used to run away. Each of those says the support under the slab has moved or washed out, and a surface treatment applied over a void simply hides it until the same movement reopens the same crack. When the ground is the problem, the fix has to reach the ground.
Ask for the quote broken into demolition and disposal, site preparation, the pour itself, and finishing. That split is where the differences live, and it lets you compare like with like instead of comparing two headline numbers.
Ask what happens if something unexpected turns up under the slab, because on a patio something occasionally does. A contractor who has already thought about how that gets handled and priced is telling you something useful about how the rest of the job will run.
And ask about the finish before the concrete is ordered, not after. Broom finish, exposed aggregate, saw-cut patterns, stamping and colour all sit on the same structural slab but diverge sharply in labour, and it is a decision made at the point of ordering.
If your patio is in the Los Angeles area, the crew we point local patio projects toward works this way, and there is a resurfacing option worth reading first if the slab underneath yours has stayed level.
The short version: the concrete is rarely what makes a patio replacement expensive. Getting the old one out, getting the new one in, and dealing honestly with what the slab is attached to and sitting on - that is the job, and a bid that shows you those parts separately is a bid you can actually judge.
Because the two jobs are priced by different constraints. A driveway is engineered around vehicle load, so its thickness, its sub-base compaction and often its reinforcement are set by what has to park on it. A patio holds people and furniture, so that structural spec is simply not required, and a contractor quoting a patio to driveway spec is quoting you a stronger slab than the use calls for. Pushing the other way is access: a driveway sits at the street where a truck, a mixer and a dumpster can reach it, and a patio usually does not. On the same square footage, the driveway is the heavier build and the patio is frequently the harder job to get materials into and rubble out of.
Look at what the crack is telling you rather than at the crack itself. Fine surface cracking with the two sides sitting level is a cosmetic and durability question, and patching or resurfacing is a legitimate answer to it. The signals that point to replacement are differential ones: one side of the crack has dropped below the other, sections rock underfoot, or the slab has tilted so that water now runs toward the house instead of away from it. Those mean the ground under the slab has moved or washed out, and no surface treatment fixes a support problem - it just resurfaces it until the same void reopens. The honest test is whether the slab is still fully supported, not whether it still looks acceptable.
Demolition and disposal, and on back-yard patios it is regularly one of the largest lines on the page. The existing slab has to be broken up and physically removed, and the weight involved is substantial. If a truck can back up to the work, that is machine work. If the only route out is a side gate and a garden path, the same tonnage leaves by wheelbarrow, one load at a time, and the labour hours climb accordingly. This is why two bids on an identical patio can differ sharply and both be honest - they may be pricing two completely different removal routes. Walk the route with whoever is bidding and you will usually find the discrepancy right there.
Often, yes, and it is worth raising before you sign rather than discovering it as a change order. Patios accumulate services underneath and around them: an irrigation line, a gas run to a grill or fire pit, low-voltage lighting, sometimes a condensate or downspout drain. Tree roots are the other common one, and a root large enough to have lifted the old slab will lift the new one too if it is simply poured over. If the patio carries a cover, a pergola or a screen enclosure, its posts are usually footed in the slab, and how those footings are handled changes the sequencing of the whole job. A contractor who asks about these on the walkthrough is doing the estimate properly.