Who is responsible for fixing a sidewalk in front of my house in Austin?

Often the adjacent property owner, when the city's sidewalk program flags a heaved or cracked panel. The replacement has to meet the city's specs for thickness, width, and slope. A small offset can sometimes be ground flush instead of replaced, which is the outcome worth asking about first, and we'll tell you which one your panel qualifies for.

When should I worry about a crack in concrete?

When it changes. A crack that widens over a season, offsets vertically so one side sits higher, or runs diagonally from a corner is reporting ground movement, and the ground gets fixed before the crack does. Hairline cracks that stay hairline, and straight cracks inside the control joints, are the slab behaving normally.

What causes concrete to spall or flake?

A surface-level failure: finishing problems on the original pour, aggressive pressure washing, deicing salts, or freeze damage, which our infrequent Texas freezes inflict surprisingly well because slabs here live wet. The concrete under the flaking is usually sound, which is why resurfacing fixes most spalling without a tear-out.

Why is one section of my concrete sinking?

The base under it failed, either washed out by water or never compacted when it was built. Downspouts, pooling, and edge erosion are the usual suspects, so the water problem gets solved first. Then a stable, slightly sunken section can be lifted, while a badly sunken one is cut out and rebuilt on a proper base.

Can heaved concrete go back down on its own?

Clay-heaved slabs can settle partway back as the soil dries, which is exactly the problem: a slab that rides the moisture cycle is cracking a little more with each round trip. The fix isn't waiting for a dry month; it's managing the water and, where the movement continues, rebuilding the section on a base that doesn't care about the weather.

Shed and Workshop Slabs: What the Building Supplier Doesn’t Mention

Ace Concrete Contractors Austin
Concrete Contractor Tips
September 2, 2026

A shed kit’s pad requirement says level and sized to the footprint; a slab that serves the building also needs square corners, anchor-ready edges, thickness matched to the shop’s contents, a vapor barrier if enclosed, and a setback check before anything’s poured.

Shed and workshop kits come with a one-line pad requirement, usually ‘level concrete slab sized to the footprint,’ and it’s technically true the way ‘a house needs a lot’ is true. The slab is the building’s foundation, and the decisions the kit’s manual skips, anchoring, thickness, moisture, placement rules, are the ones that decide whether the building goes together square, stays dry, and holds what you bought it to hold. This guide fills in what the supplier doesn’t, in the order it matters. The pour itself follows the same sequence as any slab, covered in our the sequence beneath this guide; this is the planning layer above it.

Size and square: the kit’s real tolerances

Prefab buildings are unforgiving of pads that are out of square or undersized, because the panels and tracks were cut to a drawing, not to your concrete. Standard practice pours the pad to the kit’s exact footprint or slightly proud, with corners checked diagonally, and gets the finished height right relative to the yard so the door threshold lands where feet expect it. Slightly proud beats slightly shy everywhere in this trade: an inch of extra slab is invisible under the finished building, while a pad an inch short leaves framing hanging over air and no good options at assembly time. And decide the building’s final orientation before the forms are set, since a slab can’t be rotated afterward, door-side access has opinions, and the mower needs a path around whichever side you leave it.

Thickness and anchoring: match the slab to the shop

A garden shed holding rakes and a mower is the four-inch baseline case, and it’s genuinely enough there. A workshop is a different customer: benches loaded with iron, a lathe or mill on point loads, rolling toolboxes, maybe a vehicle someday, and the slab spec should follow the heaviest honest answer, with thickened edges where walls and racks concentrate weight. Anchoring deserves equal planning, because the building will be bolted to the slab, and anchors want cured concrete and enough edge distance to grip; the anchor layout comes from the kit’s manual and belongs in the pour plan, not improvised at assembly. The load logic behind all of this is our build-timing milestones question answered in full.

Enclosed means moisture, and moisture means the barrier

The moment a slab gets walls and a roof, it becomes a floor, and floors have a moisture relationship the open-air pad never develops: ground vapor rises through concrete, and an enclosed space collects it as damp tools, musty storage, and rust that seems to come from nowhere. The fix is bought before the pour, a vapor barrier under the slab, and can’t be retrofitted after. If the plan includes a coated floor, epoxy in the workshop, the barrier is doubly non-negotiable and the coating waits on the moisture clearance our the coating clearance guide explains. Cheap insurance, one chance to buy it.

Rules first, concrete second

Accessory structures answer to more rules than people expect: setbacks from property lines, easements that quietly cross back corners of lots, coverage limits, and HOA review where covenants exist, the same review logic our the review logic guide walks through for patios. The size of the building often decides how much process applies, which is worth knowing while you’re still choosing between the ten-by-twelve and the twelve-by-sixteen. Standard sequence: confirm placement against the rules, then pour, then build, and a contractor working as your permit partner raises the question at the quote so the answer’s settled before the excavator is. When you’re ready to spec the pad against the actual kit drawing, our priced from the kit drawing prices from exactly that document.

Questions we hear on this topic

How thick should a concrete slab be for a shed or workshop?

Four inches with steel handles garden-shed duty; workshops holding machine tools, loaded benches, or a future vehicle earn more thickness and thickened edges where weight concentrates. The honest question isn’t the building’s size but the heaviest thing that’ll ever sit inside it, and the slab spec should be written to that answer.

Should a shed slab be bigger than the shed?

Match the kit’s footprint or run slightly proud, never shy: panels and tracks are cut to a drawing and won’t stretch to cover a short pad. Beyond that, extra apron in front of the door is genuinely useful, a landing that keeps mud out and gives the threshold a proper step.

Do I need a vapor barrier under a shed slab?

If the building will be enclosed, yes, and it can’t be added later: ground moisture rises through bare concrete and an enclosed shed collects it as rust, must, and damp storage. Open-air pads can skip it. Workshops headed for a coated floor need it without debate, plus a moisture test before coating.

How does a shed attach to the concrete slab?

With anchors bolted into the cured slab, laid out to the kit’s manual, which is why the anchor plan belongs in the pour plan: anchors want proper edge distance and mature concrete to grip. Assembling the building first and improvising anchors after is how walls end up fastened where the concrete’s weakest.

Do I need a permit or HOA approval for a shed slab?

Often one or both, depending on the building’s size, where it sits relative to setbacks and easements, and whether covenants include review. The slab itself is rarely the trigger; the structure on it is. Settle placement against the rules before pouring, since concrete is the least movable part of the project.

How long after pouring a slab can I build the shed?

About a week for the framing and panels, longer before heavy equipment moves in, with anchoring waiting on properly cured concrete. The curing month keeps running under the finished building either way. Get the milestone dates in writing at the pour and schedule the kit delivery to the one-week mark, not the pour date.