New Construction Plumbing in Cumming, GA

On a house built on a concrete slab, part of the new construction plumbing is fixed permanently before a single wall exists. Every toilet flange, shower drain, tub trap and floor drain on the ground floor begins as a pipe poking out of gravel, waiting for concrete. Get those positions right and the rest of the house fits around them; get one wrong and the fix involves a saw. For slab homes in Cumming, this stage deserves more planning than any other.

Laying out drains from the plans

Under-slab layout starts with the architectural plans and the fixture selections. Each drain is located from the foundation lines, with allowance for wall framing and the finished surfaces that come later. A toilet needs its flange at the right distance from the finished wall behind it, a shower drain has to land where the tile layout expects it, and a freestanding tub needs its drain directly under the tub's outlet, which varies by model. Measuring from the slab forms rather than from rough guesses keeps every point where it belongs.

Slope, sleeves and cleanouts

Beneath the stubs, branch drains run to the building drain with a steady fall toward the spot where it leaves the house. Where pipe passes through a footing or grade beam, a sleeve protects it from the weight of the concrete and allows a little movement. Cleanouts go where the code requires and where a future drain cleaner can actually reach them, preferably not beneath a kitchen cabinet. The finished underground system is then filled for its test.

Protecting the pipe during the pour

• Stubs are capped and taped so concrete and gravel stay out.
• Tub drains usually get a box-out, a small form that leaves a pocket in the slab for the final connection.
• Pipe is anchored so the concrete crew's raking and screeding cannot shift it.
• Someone from the plumbing side rechecks positions just before the pour, after the vapor barrier and reinforcement are down.

Inspections inside Cumming city limits

For addresses inside the city, the Planning & Zoning Department handles construction permits, trade inspections and certificates of occupancy. Under-slab plumbing appears on its list of required inspections, ahead of the plumbing rough-in and final.

Inspections are generally requested at least a day ahead, and that matters most at the under-slab stage, when the concrete truck is usually booked too. Call for the inspection once the test is holding, not once the pour is scheduled.

The sewer tap

The building drain leaves the slab and becomes the building sewer, which runs out to the public main. Cumming's sewer standards say no plumber or contractor may tap the city sewer until the tap has been approved in advance, and a City of Cumming inspector has to be there when it is made. Secure that approval well before the trench is opened. Where an older lateral from a previous building is still on the lot, a sewer camera inspection shows whether any of it is worth keeping.

Why mistakes here cost more

Once concrete cures over a drain, correcting it means cutting out slab, digging to the pipe and patching the floor. That is the kind of work our drain excavation crew performs on existing homes, and it is far easier to avoid on a new one. A careful layout check before the pour takes an hour, while moving a misplaced shower drain afterward can take days. On our new construction plumbing jobs, that pre-pour check is a fixed step.

Slab plumbing questions for Cumming homes

Can a drain location change after the slab is poured?

It can, but only by cutting the concrete, rerouting pipe underneath and patching the slab, which also reopens inspection and scheduling questions. Small shifts are sometimes possible with offset fittings at the fixture. For anything larger, the sensible course is to settle locations before the pour and confirm them against the fixture you actually bought.

Does a Cumming mailing address mean the city inspects the plumbing?

Not always. The Planning & Zoning Department permits and inspects work inside Cumming's city limits, but an address that carries the Cumming name can sit outside those limits in unincorporated Forsyth County, where the city's process does not apply. Confirm the parcel's jurisdiction before applying, so the permit, the under-slab inspection and the certificate of occupancy all go through the right office.

What is a box-out in a slab?

A box-out is a small form placed around a drain, usually for a bathtub, so the concrete leaves an open pocket instead of encasing the pipe. It lets the plumber connect the tub's drain assembly later at exactly the right height and position. Once the tub is set and connected, the pocket is finished off as the tub manufacturer and the inspector direct.

Planning a slab home

If your Cumming home will sit on a slab, bring us in before the forms go up. Call (404) 409-4448 and we will go over the under-floor layout with you.