What Is a Vapor Barrier Under a Mobile Home?
November 25, 2024
In this three-part series, we will talk about what is underneath your manufactured home at a Hames community. In Part 1, we discuss the vapor barrier.
A vapor barrier on a mobile home, also called a moisture barrier or ground cover, is a protective layer, typically made of heavy-duty plastic, installed underneath the home to prevent moisture from the soil from rising into the floor, insulation, and pipes.
What are the functions of a vapor barrier on a mobile home?
- Moisture Control: It blocks ground moisture from rising into the home's subfloor, which can lead to wood rot, mold, and mildew.
- Insulation Protection: It helps protect insulation materials from becoming saturated and losing their effectiveness.
- Energy Efficiency: By reducing moisture-related heat loss, it helps maintain a more consistent indoor temperature.
- Structural Preservation: Prevents damage to wooden floor joists and metal components caused by excessive humidity or condensation.
- Pest Prevention: Reduces the likelihood of pests and bugs under your home.
How a vapor barrier is installed
The vapor barrier is typically laid out directly on the ground beneath the home, covering the entire area. This is done on the initial set up of the home.
What's the difference between a vapor barrier and my home's underbelly?
The vapor barrier and the underbelly both protect your home from moisture, so they’re easy to mix up. They’re two separate layers that do different jobs.
The vapor barrier lies on the ground. It’s a sheet of heavy-duty plastic spread across the soil under your home, inside the skirting. Its job is to stop ground moisture before it rises toward the home.
The underbelly is attached to the home. Also called the belly board, bottom board or belly wrap, it’s a sheet fastened across the bottom of the floor frame. It holds the insulation in place and encloses the plumbing, wiring and ductwork under the floor.
What does a home owner need to know about the vapor barrier?
New homes are all installed with a vapor barrier at Hames Homes. It does not need regular attention and without being damaged, it can function properly with little to no maintenance. To check the health of yours, look under your home through the skirting access panel. A healthy vapor barrier covers the ground from edge to edge. If you see bare soil, torn or bunched-up plastic, or water pooling on top of the sheet, the barrier needs repair or replacement. Pooled water can also mean a drainage or plumbing problem worth looking into.
If you notice any of these signs, have a qualified manufactured home technician from Hames inspect the space under your home. Problems are far cheaper to fix when they’re caught early.