Can a concrete patio go where the old deck was?

Can a concrete patio go where the old deck was?

Yes, and for a deck built a step or two off the back door it is one of the simpler patio jobs there is. The deck comes down, what it left behind gets cleared and filled, and a concrete patio in Henderson goes in on a new base, sized to how the yard gets used rather than to the old boards.

A deck sits up at the door and a patio sits down at the grass, so the gap at the threshold becomes a poured landing. Where the old deck stood tall over a yard that falls away from the house, that landing grows into a slab of its own with steps down. The sloping-yard answer covers the landing at a back door that sits above the patio for both cases.

The rest of the work is under the boards and on the wall behind them.

What does an old deck leave in the ground?

The posts, and whatever they stand in. Under most decks there is also a patch of bare, packed dirt and a few things somebody ran under the boards because nobody would see them there. All of it gets cleared, filled or moved before the patio base goes down, so the slab never ends up resting on any of it.

What usually turns up once the boards are off:

• Each post’s footing, a poured pier, a precast block, or the stub of a post that was set straight in the dirt.
• Years of leaves and blown-in dirt, sometimes on top of landscape fabric or a layer of gravel someone spread to keep the weeds down.
• Things routed underneath, a downspout extension, the air conditioner line, a dryer vent outlet, low-voltage wire for deck lights.

The piers come out, or get broken off well below where the base will sit. Every hole they leave is filled and compacted so the slab never bridges a soft spot, and a soft spot is one of the usual reasons a slab sinks after it was poured. The fabric and the leaf mat get stripped with the top of the dirt. Anything that ran under the deck gets moved before the forms go in.

Why is the ground under an old deck often lower against the house?

The dirt pushed back against a foundation when a house is built keeps settling for years, and under a deck nobody sees it happen. By the time the boards come up, the strip along the wall often sits lower than the ground a few feet out, which tips the wrong way for a patio.

On the deck, that never mattered much. Rain fell through the gaps between the boards and landed spread out over the whole footprint, a little here and a little there, with nothing gathering it.

A slab gathers it. Every drop that lands on the patio runs off in one direction, and if the ground under the slab dips toward the house, the water heads for the foundation. So the base gets built up along the wall and pitched away, and on a strip that has sunk a few inches the most stone on the whole job goes in right against the house.

The ground under a deck was never finished, either. Nobody graded it or seeded it. It is whatever was left the day the deck went up, usually Henderson clay that swells and shrinks with the seasons, sitting in the shade for years with no grass on it.

There can be hints before the deck comes down, like a line of soil along the wall that stays dark for days after a rain, or a crawlspace that is damp on that side of the house and nowhere else. The dip itself rarely shows from the yard. The crew finds the low spot with a level at the visit, whether the deck is still up or already gone.

What about the strip of wall where the deck was bolted to the house?

When the deck comes off, the board that held it to the house comes with it, and behind that board is a band of siding or trim nobody has seen in years, with a row of bolt holes through it. Closing that up is siding or carpentry work. It gets done before the patio is poured.

The order matters because of what sits right below that strip. The patio’s expansion joint runs along the foundation at the bottom of it, and wall work done after the pour means ladders on new concrete and patching down to a joint that should be left alone.

If the wood behind that board is soft when it comes off, that is a carpenter’s job before anything else, and the patio waits for it.

Does the patio have to be the deck’s size and shape?

No. A deck’s outline was set by the lengths lumber comes in and by where its stairs had to land, not by how anyone uses the yard. The patio gets sized to the table, the grill and the walk from the back door, and that often comes out a different shape from the boards it replaces.

Some come out wider and shallower than the deck was. Some run past the old corner to reach the shade of a tree, or stop short of a corner nobody stood in. The patio page covers how much room a table and a grill need, and the outline gets marked on the ground at the visit.

Going past the old footprint puts part of the patio on lawn and part on the bare ground the deck shaded, and both get stripped down to the same firm base. A 20 by 20 broom-finished patio, about the size of a roomy family deck, runs $3,600 - $5,000 installed in Henderson County.

When should the old deck come down?

Close to the pour date, not months ahead of it. A deck torn off in late fall leaves bare ground against the house and a back door with no step down until the pouring season opens again in April. When concrete can go in around Henderson has the rest of the calendar.

Who takes the deck down and hauls the lumber away gets settled on the quote, along with the timing.