We will tell you if crawl Space Vapor Barrier Installation is not what your Duncan crawl space actually needs. Doing this stage out of order is the most common reason the work has to be repeated.
Bare soil under the house is evaporating moisture into the space every day.
Vapor barrier on piedmont and upstate ground
On clay the ground under a Duncan house holds water long after rain, so the barrier is doing two jobs — stopping soil moisture coming up, and keeping the space off ground that stays wet for days at a time.
Clay also makes Duncan crawl spaces slow to dry. The surrounding ground gives moisture back reluctantly, which is why this stage is finished against a reading rather than a date.
Duncan at a glance
| County | Spartanburg County |
|---|---|
| ZIP | 29334 |
| Elevation | about 863 ft |
| Region | Piedmont and Upstate |
Named water nearby
- Silver Lake (reservoir)
- Lake Cooley (reservoir)
- Lyman Lake (reservoir)
- Alverson Pond (reservoir)
Signs you need this
- Bare soil anywhere on the crawl space floor
- Existing sheeting that is torn, bunched or not sealed at seams
- Barrier that stops short of the walls and piers
- Crawl space relative humidity holding above 60 percent
What the work involves
What is included on a typical Duncan property:
- Clearing and preparation of the crawl space floor
- Reinforced polyethylene barrier across the full soil area
- Overlapped and sealed seams
- Barrier carried up and sealed to walls and piers
Why it is worth dealing with now
The gap between a drying job and a structural repair in Duncan is usually measured in seasons, not years.
The full method and the step-by-step for this work is on the Crawl Space Vapor Barrier Installation page, and how it behaves across the state is on the Vapor barrier in South Carolina page.
Vapor barrier in Duncan: common questions
There is already plastic under my Duncan house. Is that enough?
Often not. Most of what we find has been laid loose, has torn, or was never sealed at the seams and walls. Unsealed sheeting performs much closer to bare soil than to a finished barrier.
Will a barrier stop water that is already getting in?
No. A barrier manages soil moisture and vapor, not liquid water under pressure. If water is entering the space near Silver Lake, drainage comes first or the sheeting simply floats on it.
Will my Duncan crawl space dry out if I open the vents?
Usually not. For much of the year the air around Duncan is warmer and wetter than the crawl space, so opening it up deposits moisture on the cool joists instead of carrying it away.
My house is on a slope. Does that make it worse?
Usually. Water landing uphill of a Duncan house travels along the clay to the foundation, so intercepting it uphill often does more than extra pump capacity underneath.
Is crawl space water damage covered by insurance?
It depends on the cause, not the address. A burst pipe in a Duncan home is commonly covered; groundwater, long-term seepage and flooding usually are not, and flood damage generally needs separate cover. Photograph everything first.
Should the crawl space vents be closed?
It depends on your climate. In humid regions, open vents often bring in air that is wetter than the crawl space, which deposits moisture on cool surfaces instead of removing it — so sealing vents and controlling humidity mechanically usually performs better. In drier climates venting can work. This should follow readings, not a rule.
Vapor barrier near Duncan
We cover Duncan and the surrounding part of Spartanburg County. The same service in nearby towns:
Other crawl space services in Duncan
Crawl Space Water Removal in Duncan
Standing water pumped and extracted from under the house, then the saturated material taken out.
Crawl Space Structural Drying in Duncan
Joists, girders and subfloor dried back to a measured target with air movers and dehumidification.
Crawl Space Mold Remediation in Duncan
Contained removal of mold-affected material, HEPA cleaning, and the moisture source shut off.
Crawl Space Drainage and Sump Pump Installation in Duncan
Interior drainage to collect water, a sump and pump to lift it, and a discharge that takes it away.
Crawl Space Wood and Subfloor Repair in Duncan
Rotted joists, girders, rim joists and subfloor sections repaired or replaced once the space is dry.
Or see everything we cover in our Duncan service area, and how this service works across the state on the South Carolina page.
Crawl Space Vapor Barrier Installation in Duncan
Call (888) 724-1354 and tell us your street and what the space looks like. We will tell you whether this is the right stage to start at.
Tell us what you are seeing under the house and we will tell you what it needs.