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Concrete patios that send rain away from the house
A patio is the one slab that sits right against the back wall of the house, usually on the side of the lot that took the most fill during construction. That placement shapes almost every decision about it. The best patio quotes around Greensboro start with where the water will go and how the slab will meet the foundation, and only then get to size and finish. This page covers those questions in the order they tend to matter.
Why the slope matters more than the size
Rain that falls on a patio has to leave it somewhere. If the slab is flat or tilts even slightly toward the house, water collects against the foundation and the back door threshold every time a summer thunderstorm rolls through. Around the Triad, where downpours can drop a lot of rain in a short time, that happens often enough to matter.
What you want is a slight, even tilt toward the lawn: enough for rain to slide off promptly, not so much that a table rocks. The fall should be built into the stone base, not just shaped into the surface of the concrete. Where the yard itself runs back toward the house, the patio may need a drain along its low edge or some regrading of the surrounding lawn so the water it sheds has somewhere to go.
Downspouts deserve a look at the same time. A gutter outlet that empties onto a new patio sends a concentrated stream across the slab and, often, underneath its edge. Extending or rerouting downspouts before the pour is far easier than doing it afterward.
Crawlspace homes and the height of the slab
Many houses in Greensboro, High Point, Winston-Salem and Burlington sit on crawlspace foundations rather than basements or slabs. That affects a patio in two ways. First, the crawlspace vents and access door are often low on the back wall, and a patio poured too high can block them or direct water straight into them. Second, soil moisture next to a crawlspace foundation can affect conditions under the house, so a patio that traps water along the wall is doing the house no favors.
Before the layout is set, walk the back wall with the contractor and note every vent, hose bib, dryer outlet and access opening. The top of the finished slab should sit comfortably below the lowest vent and below the door sill, with room for the slope to carry water away. If the only way to get there is a step down from the door, that step is usually a better answer than a slab that crowds the house.
Houses on a slab foundation raise a similar question about the door threshold. A patio that ends up flush with the interior floor has no margin for water. A small drop from the doorway to the patio is normal and protects the house.
Backfill along the back wall
The soil against a foundation is almost always backfill, placed after the walls were built and often compacted poorly or not at all. It keeps settling for years. A patio poured over it tends to drop along the house side, which reverses the slope and aims water at the wall, the opposite of what you want.
Good patio preparation deals with that strip deliberately. The contractor may dig deeper near the house, replace soft material, compact the base in thin layers, or both. Ask what they expect to find along the wall and how they will handle it. If an older patio on the property already tilts toward the house, that is a strong hint about the ground there.
Shade, pollen and mildew in a humid yard
Triad back yards are often shaded by tall pines and hardwoods, and humid summers let mildew, moss and algae grow on concrete that stays damp. A patio under heavy canopy will darken and can become slick in spots unless it gets cleaned now and then. Each spring, a coating of yellow pine pollen settles over everything and washes into the pores of unsealed concrete.
None of this ruins a patio, but it affects the choice of finish and whether to seal. A light broom finish provides traction and hides grime better than a smooth trowel finish. A penetrating or film-forming sealer can make cleaning easier. Ask the contractor what they suggest for a shaded slab and how often it should be recoated.
Roots matter under trees as well. A patio placed close to a large tree will eventually meet its roots, and a thick root under the slab can lift or crack it. Keeping the slab back from the trunk, or asking an arborist about root pruning before any cuts are made, is worth a conversation early.
Sizing the patio for how you will use it
A patio sized only for a small bistro table often feels cramped once a grill, a few chairs and a path to the yard are added. It helps to set out furniture you already own on the lawn, walk around it, and mark the corners with stakes or spray paint. Leave room to push chairs back from a table and to pass behind them.
Think about where the grill will sit relative to windows, siding and the door, and where a hot tub might go later. A hot tub is heavy when full, and planning for it usually means a thicker section of slab and a separate discussion about the base. Adding a pad for one after the fact is possible, but it is simpler to plan for it from the start.
What a patio quote should spell out
- The finished size and shape, with any curves or cutouts.
- Excavation depth, especially along the house.
- Stone base material and compacted thickness.
- Slab thickness, and any thicker areas for a hot tub or heavy grill station.
- The direction and amount of slope, and any drain at the low edge.
- How the slab will meet the house, including clearance below vents and door sills.
- Control joint layout and reinforcement.
- Finish type, and whether sealing is included or recommended.
- Steps from the door or deck, if needed.
Concrete patios that send rain away from the house — common questions
Should a patio be attached to the house foundation?
Most residential patios are poured as a separate slab that sits against the house rather than tied into it. An isolation joint, a strip of compressible material along the wall, lets the patio and the house move independently. That keeps a settling patio from pulling on the foundation and keeps a stable foundation from cracking a patio. The contractor can explain whether any connection is planned and why, especially where steps or a stoop meet the wall.
How much slope does a patio need?
A patio needs enough fall that water runs off steadily without the surface feeling tilted underfoot. Contractors often use a modest, consistent pitch away from the house, though how much suits your patio hinges on its width, its texture and the lawn it drains into. The key test is simple: after a rain, water should be gone within a short while and never be left standing against the wall or the door.
Is concrete a better choice than pavers for a patio here?
Both work in the Triad. A poured slab is one unbroken sheet, so there are no sand-filled cracks for crabgrass or fire ants to colonize, and a push broom cleans it quickly. Pavers can be lifted and reset after settling, but their joints collect sand, pollen and weeds. Stamped concrete is a middle path with a paver-like look. Which suits you depends on budget, the look you want and how much upkeep you are willing to do.
Can a new patio be poured next to an old one?
Yes, though expect a visible joint where the two slabs meet and a difference in color, since weathered concrete and fresh concrete rarely match. If the older slab is tilting or cracked, extending it just ties new concrete to an old problem. In that case, replacing the whole patio is often the cleaner choice. Ask the contractor to look at the condition of the existing slab before deciding.
Does a patio need rebar?
Not always, but reinforcement is common, and the choice depends on the slab size, soil and loads. Wire mesh, rebar or fibers help keep cracked pieces tight and level. They do not stop cracks from forming, which is the job of good base preparation and control joints. Whichever is chosen belongs inside the slab, not flattened against the stone below, so ask what the plan is for keeping it off the base during placement.
Why does the patio behind my house stay wet and green?
Constant shade and humid air keep the surface damp long enough for mildew, algae and moss to take hold. A patio with low spots or a slope toward the house holds water even longer. Cleaning with a suitable concrete cleaner or careful pressure washing will lighten it, and a sealer can slow the return. If water stands for hours after rain, the slope may be the real issue and worth having a contractor check.
Can a patio be poured in the heat of a Carolina summer?
It can, with some planning. Contractors often start early in the morning, keep materials and the base cool and damp, and protect the fresh surface from drying too fast with curing compound, wet covering or a light mist. Hot, humid weather also shortens the window for finishing, which matters more for stamped work. Ask the contractor how they handle summer pours and what they will do if the afternoon turns too hot.
Talk through your project
Start with the address, what you want poured or replaced, rough dimensions, and a few photos of the area and any existing concrete.
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