Concrete & Hardscaping: questions, answered with sources
Each answer cites the public sources it was checked against, with the date it checked them. Jobs that need a licensed pro in Virginia say so, and explain the job instead of teaching it.
Concrete & Flatwork
5 answers
How do I pour a small concrete slab?
Submit a Virginia 811 locate request first, then dig out the area, set and brace forms at the right slope, and compact a firm base. Mix bagged concrete with measured water, fill the forms full depth, screed, float, edge and cut control joints, then keep the slab moist for five to seven days. Check your county's permit and zoning rules before you start.
How much does a concrete slab cost in Virginia?
There is no set Virginia price for a slab. Each contractor prices it from the volume of concrete (area times thickness), the mix, site preparation and any old concrete to remove, how a truck reaches the spot, reinforcement, finish, weather protection and permits. Ask at least three licensed contractors to price the same written specification, and get an itemized quote.
What should I ask a concrete contractor before hiring them?
Ask for the Virginia licence number and class, then check it with DPOR. Ask how thick the slab will be, how the base is prepared, what concrete mix and air content they order, where the joints go and when they are cut, how the slab is cured, who calls Virginia 811 and handles permits, and what the written contract and warranty cover.
Why does new concrete crack?
Concrete shrinks as it sets and dries, and it cracks wherever that shrinkage is held back. Most early cracks come from joints that are missing, too far apart or cut too late, a poorly compacted base, too much water in the mix, the surface drying too fast on a hot or windy day, or too little curing. Many are cosmetic; wide, growing or uneven cracks need a look.
How long should new concrete cure before I drive on it?
Keep cars off until the slab reaches the strength its mix is designed for, and ask the contractor for that date in writing. As a benchmark, VDOT keeps vehicles off its new concrete sidewalks for 14 days, or less if design strength is reached sooner. Allow longer in cool weather, keep heavy trucks off until the contractor confirms full strength, and keep the slab moist for the first week.
Concrete Repair
5 answers
How do I fix cracks in a concrete driveway?
Open the crack to at least 1/4 inch with a chisel, brush out the loose material, and fill it with a concrete crack sealant or repair caulk, using backer rod in deep cracks. Sealing keeps water and grit out; it does not fix the cause. A crack where one side has dropped, that keeps widening, or shows rust needs a pro.
How much does concrete repair cost in Virginia?
There is no set price for concrete repair in Virginia. The kind of repair decides most of the cost: sealing cracks is priced by length and is the cheapest, patching and resurfacing are priced by area, and lifting or replacing a slab costs the most. Get three written quotes for the same scope from licensed contractors.
Should I repair or replace cracked concrete?
Repair it when the cracks are narrow, both sides sit level and the surface is sound or only lightly flaking. Consider replacing it when the slab is broken into loose pieces, sections have sunk or heaved, the surface is flaking away worse each winter, or rusting steel is pushing concrete off. A sunken but unbroken slab can often be lifted instead.
Why is my concrete spalling?
Flaking on outdoor concrete that stays wet through freezing and thawing is called scaling, and deicing salt makes it worse, especially on new concrete. Other causes are a surface finished while water was still rising through it, steel rusting near the surface, and certain stone in the mix. Shallow flaking can be resurfaced; rust or hollow areas need a pro.
How do I keep concrete from cracking in winter?
Keep water out of the concrete and go easy on deicers. Seal cracks and joints in the fall, apply a breathable water-repellent sealer to dry concrete, and make sure water drains off the slab. In winter, shovel first, use as little deicer as you can, and use clean sand instead on new concrete.
Driveways
5 answers
How thick should a concrete driveway be?
For a home driveway that carries only passenger cars, 4 inches of concrete is enough, and 5 to 6 inches is recommended where trucks or other heavy vehicles will use it. Thickness only works on a firm, compacted base, with a freeze-resistant mix, well-placed joints and a slope that drains. Put the thickness in the written quote.
How much does a concrete driveway cost in Virginia?
There is no single price for a concrete driveway in Virginia. Each contractor prices the job from your site: the area and thickness, the base, tearing out an old driveway, truck access, the mix and the apron at the street, which may need a road permit. Write one specification and get at least three written bids on it from licensed contractors.
Do I need a permit to widen my driveway in Virginia?
Often not a building permit, but other approvals are common. Widening where the driveway meets the street needs the road owner's permit: VDOT on state-maintained roads, or your city or town on local streets. Your locality may also apply zoning setbacks and land-disturbance rules, and you must call Virginia 811 before digging. Check with the building office and road owner first.
Why is my concrete driveway sinking at the garage?
The garage floor sits on the house foundation, but the last few feet of driveway usually sit on soil that was dug out and backfilled when the house was built. That fill keeps settling, and roof water from gutters and downspouts near the garage softens and washes it out. Clay soil that shrinks in dry spells adds to it. Fix the water first, then lift or replace the slab.
How do I protect a new concrete driveway in its first winter?
Keep deicing salt off it for the first winter, about a year, and use clean sand for traction instead. If it was poured late in the year, it needs protection from freezing in its first 48 hours. Shovel early so snow does not pack into ice, hose off road salt that cars carry in, keep meltwater draining off, and seal it the following late summer.
Fire Pits & Features
5 answers
How do I build a fire pit with pavers?
Pick a spot that meets your county or city's distance rule, call Virginia 811, dig out a circle, compact a crushed-stone base in layers, then stack wall blocks in level, staggered rings around a steel insert or firebrick lining, and finish the floor with a layer of lava rock. This covers wood-burning pits only.
How much does it cost to build a fire pit in Virginia?
It depends on what you build. A block kit around a steel insert is the simplest built-in option, while custom masonry with firebrick, a poured concrete pit, a paver patio and seating wall, or a gas burner each add materials, labor and sometimes permits. Prices vary by job and site, so get at least three written, itemized bids.
Are backyard fire pits allowed in Virginia?
Suffolk and Fairfax County allow them with conditions, and your county or city sets the rules. Suffolk permits recreational fires no bigger than 3 feet across and 2 feet high, more than 25 feet from any structure. Fairfax has separate rules for recreational fires and portable fire pits, so ask its fire marshal which covers a built-in pit. The 4 PM Burning Law, burn bans and HOAs also limit burning.
Why does my fire pit smoke so much?
Wet or unseasoned wood is the usual cause, because green wood smolders instead of burning hot. The other common causes are a fire starved of air by packed logs, deep ash or a pit with no air vents, and the wrong fuel, such as leaves, yard waste, trash or treated wood. Dry, split, well-seasoned firewood in a small, hot fire smokes far less.
How do I keep a fire pit from cracking?
Keep the flames off the concrete. Line the pit with a steel insert or firebrick, keep fires modest, and let new concrete or mortar cure fully before the first fire. Then keep water out: keep the floor clear of packed ash, cover the pit when it is cold, and repair loose firebrick joints with a heat-rated mortar before small cracks spread.
Outdoor Kitchens
5 answers
What does building an outdoor kitchen involve?
An outdoor kitchen is four trades in one project: a base and island built to the grill maker's clearance rules, a gas line sized for the appliances, a GFCI-protected electrical circuit, and often water and a drain for a sink or ice maker. The gas, wiring and plumbing need permits and licensed tradespeople in Virginia, so plan and hire it as a small construction job.
How much does an outdoor kitchen cost in Virginia?
There is no honest single figure, because an outdoor kitchen can be a grill set in a block island or a full kitchen with refrigeration, a sink and a vent hood. The price is set by the appliances, the island material, how far gas, power and water must run, and the permits. Get at least three written, itemized bids on the same plan.
Do I need a permit for an outdoor kitchen in Virginia?
Usually yes, for the utilities. Virginia's building code requires a permit for new gas piping, electrical wiring and plumbing, which most outdoor kitchens include. A masonry island under six feet tall on an existing patio, with a grill on a portable propane cylinder, may need no building permit, but zoning, HOA and site rules can still apply. Confirm with your locality.
Why is my outdoor kitchen grill burner not lighting?
Usually because no gas is reaching the burner, the igniter has no spark or power, or something is blocking the burner. Common causes are a closed shut-off or empty propane cylinder, a regulator that tripped, a tripped GFCI outlet, chewed igniter wires, and spiders nesting in the venturi tubes. If you smell gas, stop and get a qualified gas technician.
How do I winterize an outdoor kitchen in Virginia?
Winterizing an outdoor kitchen means protecting four things before hard freezes: the refrigerator and ice maker, which makers say to shut down and drain; the water lines and sink, which must be emptied so they cannot burst; the grill and its gas supply; and the stainless and stone surfaces. Have a plumber drain lines that were not built to drain easily.
Patios & Pavers
5 answers
How do I lay a paver patio?
Have Virginia 811 mark buried lines, dig out the area, compact a crushed-stone base (4 to 6 inches is the usual range for a patio) in layers of 3 to 4 inches with a slight slope away from the house, set an edge restraint, screed a layer of loose bedding sand, lay the pavers, then compact them and sweep joint sand in until the joints are full.
How much does a paver patio cost in Virginia?
It depends mostly on size, how much digging and base the soil needs, the pavers you choose, the pattern and number of cuts, and site access. There is no current dated statewide price, so get at least three written bids on the same specification: base depth, compaction, edge restraint, sand, pavers and joint fill.
Are pavers or poured concrete better for a patio?
Neither is better everywhere. Pavers are many small units on a compacted base, so a low spot can be lifted and relaid without a patch, but the joints need sand upkeep and the edges need a restraint. A poured slab is one continuous surface with less routine care, but it is prone to cracking, so joints are cut to control where.
Why are my pavers sinking?
Usually because something underneath has moved: soil or gravel base that was not compacted well, a base or soil that stays saturated, bedding sand laid too thick, sand washed out by a downspout or pressure washer, or an edge restraint that has failed. A shallow low spot can usually be lifted, corrected and relaid with the same pavers.
How do I keep weeds from growing between pavers?
Keep the joints full and clean. Weeds between pavers grow from seeds that land in the joints, mostly in dirt and debris that collects on top, so sweep the patio in spring and fall, pull weeds while they are small, keep joint sand topped up, and consider polymeric sand. Plastic sheeting under the pavers does not help.
Retaining Walls
5 answers
What does building a retaining wall involve?
Most of a retaining wall is work you never see: checking utilities and permits, choosing a design that suits the height, soil and anything above the wall, building it on a firm compacted base, and filling behind it with drainage stone, a perforated drain pipe and compacted soil. Taller walls, and walls holding up a driveway or patio, need a permit and often an engineer.
How much does a retaining wall cost in Virginia?
There is no single Virginia price. Cost follows the wall's height and length, the material, whether it needs an engineer and a permit, how much drainage stone, pipe and imported backfill it takes, your soil, and access for equipment. Permit fees are local: Fairfax County's schedule effective July 1, 2026 charges 3 percent of the estimated construction cost for a house's retaining wall.
Do I need a permit for a retaining wall in Virginia?
Usually, once the wall holds back three feet of soil or more. Virginia's building code exempts only retaining walls supporting less than three feet of unbalanced fill with no surcharge such as a driveway or patio above. Counties add their own rules: Fairfax and Prince William also treat tiered walls specially, and Prince William requires zoning approval for any retaining wall.
Why is my retaining wall leaning?
A retaining wall leans outward when the soil and water behind it push harder than the wall, its base and any reinforcement can resist. The usual causes are water trapped behind it, clay or organic backfill, a base on soft soil, a wall too tall for its design, or extra weight above it. A slight lean back into the slope is normal for block walls.
How do I keep a retaining wall from failing?
Keep water out from behind it and weight off the top. That means drain outlets kept open, downspouts, sprinklers and runoff sent away from the wall, no new patio, driveway, pool or steeper slope above it without an engineer, and a look at it a couple of times a year for lean, bulges and cracks. The rest depends on how well it was built.
Sealing & Resurfacing
5 answers
How do I seal a concrete driveway?
Pick a dry stretch of mild weather, clean off oil and dirt, fill cracks, let the slab dry for at least a day, then spray or roll on a breathable penetrating sealer evenly at the coverage rate on the label, with no puddles. Keep cars off for the wheel-traffic time the label gives.
How much does concrete sealing cost in Virginia?
The price of sealing concrete in Virginia depends on the square footage, the sealer, the prep, any old sealer that has to come off and how many coats. Doing it yourself costs a few gallons of sealer plus cleaning supplies. For a contractor, compare at least three written, itemized bids and check the licence: DPOR says work valued at $1,000 or more needs a Virginia contractor licence.
Should I seal concrete myself or hire someone?
Seal it yourself if the concrete is sound, has no old coating and you are using a water-based penetrating sealer; some, such as Quikrete's waterproofing sealer, go on with a roller or garden sprayer. Hire a licensed contractor for old sealer that is white or peeling, a glossy film finish, solvent-based or professional-only products, or a surface that is flaking or cracking.
Why does my concrete sealer look white or cloudy?
Usually because the sealer went on too thick, went onto damp concrete, or dried in weather that was too cool or humid for it. A solvent-based acrylic turns white when moisture is trapped under it; a water-based one dries milky if it cannot form a film. White, powdery deposits can also be efflorescence, salts carried up by water, which is a different fix.
How often should concrete be sealed?
Reseal when the concrete tells you to, not on a calendar: when water stops beading and soaks in, darkening the surface. Euclid's penetrating sealers usually go at least five years before that happens. Film sealers vary by product, so follow the label, and sealing more often than needed builds up a film that can whiten and peel.
Sidewalks & Steps
5 answers
How do I fix crumbling concrete steps?
Chip away every loose piece until you reach solid concrete, clean and dampen it, then match the product to the damage: a vinyl concrete patcher for thin, shallow spots on the treads, and quick-setting cement with an acrylic fortifier to rebuild broken edges and corners. Keep people off the patch for a day. Steps that are cracked through, tilting or pulling away need a contractor.
How much do concrete steps cost in Virginia?
There is no reliable statewide price for concrete steps in Virginia. The cost depends mostly on whether you are patching, resurfacing or tearing out and pouring new steps, how many steps and how big a landing, whether old concrete has to be broken up and hauled away, and whether a permit and handrail are needed. Compare three written quotes for the same scope.
Who is responsible for fixing the sidewalk in front of my house in Virginia?
It depends on who owns the street. Cities, towns, and Arlington and Henrico counties maintain their own streets; in the rest of Virginia's counties VDOT maintains most roads. A sidewalk belonging to the locality or VDOT is generally theirs to fix, but your driveway apron is usually yours, local rules vary, and localities may charge abutting owners for sidewalk work. Report damage before repairing anything.
Why are my concrete steps pulling away from the house?
Almost always because the soil under the steps has settled or moved. Front steps usually sit on the soil that was dug out and refilled around the foundation, which keeps settling for years, and roof water, poor grading and clay that shrinks in dry weather make it worse. A narrow gap that stays put can be sealed; a widening gap or tilting steps need a contractor.
How do I keep concrete steps from crumbling?
Keep water and salt out of the concrete. Shovel first and use as little deicer as you can, and use sand instead on steps in their first winter. Keep roof water off the steps, seal them with a penetrating silane-siloxane sealer on a dry day within the temperature range on the label, and patch small chips each spring before freeze-thaw cycles turn them into bigger damage.
Slab Lifting & Leveling
5 answers
How does mudjacking or foam slab lifting work?
Both methods raise a sunken concrete slab by pumping material into the gap beneath it through holes drilled in the concrete. Mudjacking uses a cement-based grout and larger holes. Foam lifting uses a two-part polyurethane that expands under the slab through much smaller holes. In both, the crew raises the slab a little at a time while watching its level so it does not crack.
How much does concrete leveling cost in Virginia?
Concrete leveling in Virginia has no standard price, because the amount of material a slab takes can only be judged on site. The price depends on the area lifted, the size of the void underneath, foam or cement grout, the prep around the slab, and any drainage fix. Get at least three written quotes for the same slabs from licensed contractors.
Is slab lifting or replacing concrete the better choice?
Lift the slab when it has sunk but is still mostly in one piece and the ground under it can be made stable. Replace it when it is broken into loose pieces, has heaved rather than sunk, or the soil underneath has to be dug out and rebuilt. Either way, fix the water or soil problem that moved it, or it will move again.
Why is my concrete slab sinking?
A slab sinks when the soil under it stops holding it up. Common causes are fill that was not compacted well before the pour, water from downspouts or poor drainage softening or washing out the base, and clay soils that shrink in dry weather. Find and fix the cause before lifting or replacing the slab, or it will sink again.
How do I keep a slab from sinking again after it is lifted?
Fix whatever made it sink. Send roof water well away from the slab, make the ground slope away from it, keep joints and cracks sealed so rain cannot reach the soil underneath, and on clay soils keep the moisture under the slab steady. Ask the contractor to confirm every void was filled, and get any warranty in writing.
Stamped & Decorative
5 answers
How do I clean and reseal stamped concrete?
Wash the surface thoroughly, let it dry completely, then apply one thin, even coat of a sealer that is compatible with the one already on it, at the label's coverage rate, in shade and mild weather. Reseal when water stops beading or the color looks flat, not on a fixed schedule, because extra coats build up and fail.
How much does stamped concrete cost in Virginia?
There is no published Virginia price for stamped concrete. Each contractor prices it from the slab itself (size, thickness, base and access), the coloring method, the pattern and borders, the joints, and the sealer, plus resealing every few years. Get at least three licensed contractors to price the same written specification and compare itemized quotes.
Is stamped concrete a good choice for a patio in Virginia?
Often, yes, if it is built for freeze-thaw winters and you accept the upkeep. Ask for air-entrained concrete of the right strength, a well-compacted base, joints planned into the pattern and a sealer suited to outdoor use. Expect to reseal every few years, keep salt off it, and know that cracks and patches are hard to hide.
Why is my stamped concrete fading?
Often because the sealer has worn thin, since sealer is what deepens the color. As a rough check, if the color comes back when you hose it down, worn sealer is the likely cause and a clean and reseal usually helps. Other causes are a sealer turning white, efflorescence, the accent color wearing off the high spots, and surface damage from freeze-thaw and deicing salt.
How do I keep stamped concrete from getting slippery?
Mix a slip-resistant additive into the final coat of sealer next time you reseal, and do not pile on extra coats for shine. Between reseals, keep the surface clean of leaves, mildew and standing water, and in winter use sand for traction instead of heavy salt. A lower-gloss or penetrating sealer also leaves a less slick surface.