Under-Home Moisture & Drainage in Myrtle Beach

Water under a mobile home is the problem that causes the other problems. Saturated sand under a pier pad compacts and washes, which is how piers drop and homes go out of level, and an open wet crawl loads moisture into your floor system every day it sits there. A free under-home inspection comes first, then a written price: ground vapor barrier $400 to $1,200, grading and drainage work $300 to $1,500, washout repair from $150 per pier.

Almost nobody calls about this. They call about a sloping floor eighteen months later.

What “wet under the home” actually looks like around here

On the Grand Strand there are four different situations that all get described as water under the home, and they cost very different amounts to fix.

Saturated ground, no standing water. The sand is simply damp all the time because the water table is close to the surface. Common near the marsh in Little River, along the Intracoastal in Socastee, and through the river lowlands around Conway. The fix is a ground vapor barrier so the moisture cannot rise into the crawl, and it is the cheapest thing on this page.

Standing water after rain that drains within a day or two. The lot sheds water toward the home rather than away from it, usually because the grade is flat or has settled over the years, and often because roof runoff is landing right at the skirting. Grading, a swale, splash blocks, and moving downspouts fix most of these.

Standing water that stays for weeks. Now the lot is a low spot, and the water table under it is coming up to meet the surface. This one is honest work: it needs real regrading and sometimes a drain line to somewhere the water can go, and it will not be solved by a barrier alone.

A channel or hole opening beside the home. This is a washout, and it is the urgent one. Water taking the same path repeatedly carries sand away, and if that path runs near a pier line it is quietly removing the ground the pad is bearing on.

Why this matters more than it sounds

Every part of Horry County sits on coastal-plain sand. Sand drains fast on the surface and holds water underneath, and under the concentrated load of a pier it compacts and migrates when saturated. That mechanism is the reason releveling here is a three-to-five-year maintenance cycle rather than a one-time repair.

So a wet lot does not just make a home damp. It shortens the leveling interval. A home with proper drainage might go five years between relevels; the same home with water running under it will need one every two or three, and each of those will involve more pier and pad work than the last, because the pads keep pressing into ground that never gets a chance to firm up.

Fixing the water is the cheapest leveling work you will ever buy, because it is the work that stops you buying the other kind.

The rain here does not help. Ordinary summer thunderstorms saturate the county every year, and tropical systems do worse: Florence in 2018 dropped 23 inches on Horry County and put the Waccamaw at a record 21.16 feet at Conway, with around 2,000 homes flooded, many outside mapped flood zones. Lots that took water in a storm like that are the ones with washouts nobody has looked for.

What the job includes

1. Free inspection, and a real diagnosis. We crawl the length of the home, find where the water is arriving from, look at the grade around the outside, check the roofline and downspouts, and read the pier pads for evidence of washout or sinking. You get a written price from that.
2. Stop the source. Regrading to shed water away from the home, swales where the lot needs a path, splash blocks and downspout extensions where roof runoff is doing the damage. This comes before anything else, because covering wet ground without stopping the water just traps it.
3. Ground vapor barrier. Heavy sheeting across the crawl floor, lapped and sealed at the seams and run up to the skirting line, so moisture from the soil stops rising into the space at all. This is the single highest-value item on the list for most Horry County homes.
4. Washout repair. Where sand has been carried out from under a pad, the void gets filled and compacted properly and the pad reset, rather than dropping a block on top of loose fill and calling it done. Quoted per pier.
5. Airflow, last. Vents get cleared or added once the ground is covered and the water is stopped, which is the order that actually works in this climate.
6. Everything else found, priced. A wet crawl almost always comes with a torn belly wrap and often with piers that have already moved. You get the whole list with numbers on it and no pressure about any of it.

What this is not

We are not going to sell you a sealed and conditioned crawl space encapsulation system for a manufactured home on blocks. That is a stick-built product, it is expensive, and on a home with a skirting perimeter it usually does not do what the brochure says.

We are also not going to tell you that a dehumidifier fixes a drainage problem. It does not. It manages the symptom while the sand under your piers keeps moving.

Get it looked at before the wet season decides for you

The under-home inspection is free, takes about half an hour, and you get a written price whether or not you book anything. If the ground under your home is dry and the grade is fine, that is what we will tell you.

The best time to do this work is a dry stretch, which on the Grand Strand means late autumn through spring. The worst time is the week after a named storm, when every crew in the county is booked and the damage is already done. If you have seen water standing under your home this summer, or a channel opening beside it, that is the signal.

Whoever does the drainage work, ask for their licence and insurance before they start. Ranges are on the pricing page, and the self-check will tell you whether the piers have already started to move.